f W 1 e : THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID X J . THE MUSCULAR MOTIONS OF THE HUMAN BODY. By JOHN BARCLAY, M.D. LECTURER ON ANATOMY, FELLOW OF THE ROYAL COLLEGE O PHYSICIANS, AND OF THE ROYAL SOCIETV OF EDINBURGH, &C. &C, EDINBURGH : PRINTED FOR W. LAING, AND A. CONSTABLE AND CO. EDINBURGH ', AND LONGMAN, HURST, RFES, AND ORME, AND J. MURRAY, LONDON. 1808. TO DR THOMAS THOMSON, LECTURER ON CHEMISTRY, AND FELLOW OF THE ROYAL SOCIETY OF EDINBURGH. DEAR SIR, L HOUGH you be not so much interested in Ana- tomy as in that science which so widely extends your fame over Europe, and is likely to extend it to distant posterity ; yet knowing the interest also which you take in whatever tends to illustrate the functions of the animal system, I dedicate to you the following Treatise on the Muscular Motions of the Human Body : happy in having this op- portunity of acknowledging with what affection and esteem, I ever am, DEAR SIR, Your sincere friend, JOHN BARCLAY. M37O546 TO MY PUPILS. GENTLEMEN, Ju ROM the very few elementary substances that enter into the nourishment of plants, regarded as simple, because chemistry has not yet analysed them, are produced all the wonderful varieties of so- lids and fluids, of magnitudes and forms, of odours, of colours, and of organizations, that are to be found in the vegetable kingdom. By new combinations of the same substances, are likewise produced all the varieties of solids and fluids, of magnitudes and forms, of odours, of colours, and of organiza- tions, that distinguish the different species of ani- mals. These varied and endless combinations in the works of Nature, all of them obviously regula- ted by design, must imply degrees of wisdom and power, as much superior to those which are indi- cated in the works of art, as the unbounded Vlll [DEDICATION. ledge of Deity surpasses the limited intelligence of man. The mode, however, in which many of these combinations are formed, must, from their minuteness, for ever elude the most penetrating eye ; and from their intricacy, or from unknown causes concerned, lor ever bid defiance to human research. It is only in the muscular motions of animals, that the wonderful manner in which many of these combinations are formed, may be traced to causes that are visible, distinct, and within the reach of every observer; and this happy and illus- trative instance of the method in which the Sove- reign of the Universe produces an incalculable variety of effects, by the means of a few secon- dary agents^ must render the motions of the ani- mal system highly interesting to every studious philosophic mind. By the varied and combined actions of the mus- cles, which every man sees, or easily may $ee t there is formed an exhaustless source of distinc- tions for every individual of the human species^ not only in the expressions of the countenance, the articulation, the tone of voice, and the hand- writing, but in the motions of walking and run- DEDICATION. M> ning, in the attitudes of standing, and the mode of placing the foot upon the ground. By the same species of combined action, are likewise pro- duced all the singular varieties of language, that have ever distinguished, that now distinguish, or that ever will be found to distinguish nations ; all the singular species of exercise , and all the va- ried operations of art. In tracing these pheno- mena to their source, the philosopher and di- vine might find almost innumerable proofs of the power, the wisdom, and the providence of Deity ; and might thence inculcate, with more than ordi- nary clearness and force, some of the most useful and important truths that ever were impressed on the human mind. It was not, however, with such views that I un- dertook the following Treatise on the Muscular Mo- tions of the Human Body. Through the whole, my attention has been chiefly directed to ex- tend your knowledge of the animal functions ; and through that medium, so far as the muscular func- tions are concerned, to improve the science of physic and surgery. Though WinskAv and others have occasion- ally shown how a knowledge of the muscles may X DEDICATION. often be useful in ascertaining the nature of symp- toms, and in leading to the proper methods of cure, the subject is far from having attracted that degree of attention to which it is entitled. In works on anatomy, the muscles in general are ar- ranged only according to regions ; and arranged in that way chiefly with a view to be subservient to the purposes of dissection. That such arrange- ments are useful and necessary, every person of candour will admit : But in describing the muscles of a region, where those belonging to different motions are classed together, if the teacher of ana- tomy, from indolence, neglect, or any other causey shall content himself with merely assigning to each muscle its separate use, or with sometimes mentioning the compound action of it and its fel- low, the student can derive but little advantage from such information ; there being no motion in the body that at once is performed, moderated, and directed by a single muscle, or a pair of mus- cles. He even may see every muscle in its turn, may hear a minute and accurate description of its form, its situation, its use, and its attachments ; and yet be as ignorant, or nearly as ignorant, of the motions of the body, as when he first entered DEDICATION. XI on his studies. What is even worse, he may be naturally led to infer, that myology itself is of no use in the practice either of surgery or physic, ex- cept when occasionally the knowledge of a muscle may happen to assist him in discovering the si- tuation of an artery or nerve. To obviate conclusions so absurdly erroneous, so flattering to indolence, ignorance, and presumption, but so very inimical to the zeal and ardour of pro- fessional improvement, besides exhibiting arrange- ments of the muscles according to regions, and ar- ranging those peculiarly belonging to the osseous structure according to the bones to which they are attached, I have arranged the whole of the muscles belonging to the system according to the motions in which they co-operate. From the first of these species of arrangements, you will see what mus- cles are likely to be supplied with the same branches of arteries and nerves ; from the second, what parts of the osseous structure are connected by muscles ; and from the third, what muscles co- operate, and how they co-operate, in performing their motions. From the whole, you will learn the nature and causes of a number of sympathies that arise from attachment, situation, and func-* 3 Xil DEDICATION. lion ; be able to explain many singular symptoms that occur in disease ; and often be able to pro- vide a safe, expeditious remedy, where others, that are less acquainted with myology , would be torturing their patients with all the contrivances of ignorant empiricism *. In cases, particularly, of luxation and fracture, you will readily perceive what are the motions that are best calculated to favour the reduction ; what are the muscles that are fitted to assist, and what to oppose you in the operation ; what are the positions that are best suited to preserve the case and security of the parts; and what the motions, attitudes, and muscles most likely to dis- turb them. Hitherto the surgeon, in these ope- rations, has seldom called in, and could seldom call in, the aid of myology ; and hence, his suc- cess depending so much on force, accident, or manual dexterity, he has sometimes been equal- led, and, with the vulgar at least, been often sur- passed, in point of reputation, by the ignorant bone-setter. To remove, Gentlemen, even the chance of such a comparison, let me earnestly ad- J Sec p. DEDICATION. Xlll vise you to study the compound actions of muscles ; the only way in which you can ever possibly understand the admirable mechanism of the human body. By thus adding science to art, though you cannot always expect to be success- ful, yet, by a patient and steady perseverance, you may reasonably hope to bring the treat- ment of luxation and fracture to a much higher de- gree of perfection than it has been hitherto. Through the whole of this Work, I have inva- riably adhered to the terms of position and aspect which I formerly recommended in my Nomen- clature ; tfyese terms being more precise than the Vague terms that are usually employed, and which change their meaning with every slight change of position. If the Work has been delayed beyond the pro- mised time of publication, it was not from either indolence or neglect to fulfil my engagement. I did not foresee the many interruptions and the many difficulties which I had to encounter. It is now, however, brought to a close ; and such as it is, I present it to you, containing some errors which I have corrected, and many perhaps which I have not seen. If it be so fortunate as to add to your K1V DEDICATION*. knowledge of the Animal Structure, or improve your practice in Physic and Surgery, I shall think my labour amply rewarded. And with much in- terest in the progress of your studies, success in your profession, and prosperity in life, I remain, GENTLEMEN, Your much obliged, And sincere well-wisher, JOHN BARCLAY. CONTENTS, PART I. Containing arrangements of the muscles into regions, with the names of Albinus alpha- betically arranged, and under each name the different sjnonyms. Arrangement of Albinus Page 1 Arrangement of Innes 18 Arrangement of Dumas 34 Names of Albinus alphabetically arranged, with the different synonyms of Innes and Dumas, and references to the regions in which they are found 51 Names of Albinus alphabetically arranged, with all the synonyms prior to Albinus, and by whom used 72 PART II. Containing the muscles peculiarly belonging to the osseous structure, and arranged ac- cording to the several bones to which they are attached, with general observations oa CONTENTS. the different parts constituting a musck, and general observations on muscular ac- tion. Arrangements of the muscles according to the bones.., , , 164 General observations on the different parts constituting a muscle 217 General observations on muscular action...... 270 PART III. Containing different arrangements of the muscles, according to the motions in which they co-operate, and occasional explana- tions also of the manner in which they co- operate. Motions of the head 312 Motions of the neck., 328 Motions of the trunk 337 Motions of the trunk on the head, neck, and four extremities 369 Motions of the atlantal extremities 371 clavicle 372 scapula 374 bumerus 381 ulna and radius ^... 393 ulna 396 radius.. , 39B CONTENTS. XVII carpus 400 bones of the carpus 404 bones of the metacarpus 406 , digital phalanxes. 407 thumb * 408 fingers * 411 Motions of the sacral extremities 418 femur *.. 426 tibia 433 fibula , 442 tarsus , 443 bones of the -tarsus.. ... 447 bones of the metatarsus ib. bones of the tarsus and meta- tarsus..... +..1 448 digital phalanxes 451 great toe ib. small toes 452 Motions of the auricle 456 bones of the tympanum...... 458 cutis covering the cranium and face........... 461 brows, eyelids, nostrils, lips... 463 eye , < 468 basilar maxilla.................. 482 tongue....,..., 490 os hyoides '.... . 495 larynx. .....^ 498 pharynx 503 velum pejadulum palati. ...... 506 b XViil CONTENTS. Motions of respiration 5l4 of the alimentary canal 541 in the expulsion and retention of urine 555 of the male organs of generation.... 558 of the female organs of generation. . 562 of the sanguiferous system..... 565 A Short EXPLANATION of the several Terms of POSI- TION and ASPECT** Aspects of the Head, Neck, and Trunk. AN imaginary plane, dividing the head, neck, and trunk into similar halves, towards right and left, is the mesial plane. Every aspect towards this plane is mesial, and every aspect towards right or kft, lateral ; every lateral aspect being dextral or sinistral. no . Aspects of the Head. An aspect towards the plane of the war, or ridge of the occiput, is inial ; towards the plane of the corona, coronal ; towards the base, basilar ; to- wards the glabella, glabellar ; or towards the side opposite to the inion, antinial. /.y no ^ "* ; "* For a fuller account of the nature and extent of their ap- plication, and of the 'principles on which they are adopted, see the treatise on a New Anatomical Nomenclature* EXPLANATION OF THE TERMS Aspects of the Neck and Trunk. An aspect towards the region where the atlas is situated is atlantal ; towards the region where the sacrum is situated, sacral ; towards the dorsum, dorsal ; and towards the plane of the sternum, sternal. Aspects of the Four Extremities. An aspect of a bone towards the trunk, in the ' course of the extremity, is proximal ; and if from the trunk in the course of the extremity, distal. Aspects of the Atlantal Extremities. An aspect towards the side on which the radiu$ is situated is radial ; if towards the side on which the ulna is situated, ulnar ; if towards the side on which the ancon is situated, anconal ; and if to- wards the side on which the vola or 8^ is situ- ated, thenaL Aspects of the Sacral Extremities. TRW An aspect towards the side on which the tibia is situated is tibia! ; if towards the side on which the fibula is situated, fibular ; if towards the side on which the rotula is situated, rotular ; and if to- wards the side on which the poples is situated, po- pliteal. OF POSITION AND ASPECT. Jenns of Aspect common to the Head, Neck, Trunk, Extremities, and Viscera. An aspect towards the cutis, dermal ; if towards the circumference of any part, peripheral ; and if towards its centre, central. When d is substituted for the / or r that termi- nate these adjectives, they become adverbs, or are used adverbially ; so that coronad, iniad, glabettad, radiad, ulnad, tibiad,jibulad, -c. will respectively signify towards the coronal, inial, glabellar, radial, ulnar, tibial, and fibular aspects, . PART I. CONTAIN ING ARRANGEMENTS OF THE MUSCLES INTO REGIONS, WITH THE NAMES OF ALBINUS ALPHABETICALLY ARRANGED, AND UNDER EACH NAME THE D1F- > '-. FERENT SYNONYMS. OP THE MUSCULAR MOTIONS THE HUMAN BODY. REGIONS into which the Muscles arc arranged according to ALBINUS. i. CALVA. Epicranius II. Circa Auriculam. Attollens auriculae Anterior auriculae Retrahentes tres, superior, medius, inferior III. Fades. Orbicularis palpebrarum Corrugator supercilii A REGIONS OF ALSINUS. Compressor narium Levator labii superioris alaeque nasi Levator labii superioris Zygomaticus minor Levator anguli oris Zygomaticus major Depressor anguli oris Depressor labii inferioris Nasalis labii superioris Buccinator Orbicularis oris Depressor alae nasi Levator menti IV. Mala et Lotus Calvb singularem et a musculis tantopere discrepantem REGIONS OF ALBINUS. 13 figtlram, et conformationem, non musculum, sed partem musculosam dici : sphincterem vero vesi* cse, aliosque ejus generis e fibris constantes con- textus, quia partim in musculos proprie collecti non sunt, partim ex fibris albicantibus, non autem car- neis constant ; in musculorum humero non videri reponendos, nisi et musculosum stomachi et vesica^ urinariae, et e fibris contextum ventriculi et intesti- siorum involucrum aliasque plurimas fibras, quae multis partibus intextae sunt, musculos appellare ; eoque verorum musculorum historiam turbare ve- limus. At quosdam tamen, qui aut veri musculi sunt, aut certe ipsis quam simillimi retinendos ex- istimavimus ; ut Attollentes auric alarum Tragicos Antitragicos aliosque similes. Regions II. IV. V. VI. VII. IX. XI. XIII. XX. XXIL XX'm. XXIV. XXV. XXVL XXVII. XXVIII. XXIX. XXX. are lateral regions, and consequently double. If reckoned separately, the. number of regions will amount to forty-eight. But of these forty-eight, three are peculiar to the male ; namely, the XVII. circa perineum viri, and the XIII. circa funem sperrnaticiim et testem, considered as two. To the remaining regions, which are com- mon to both sexes, the female adds one. See re- gion XVII. So that the male, according to Albi.- 14 REGIONS OF mis, has forty-eight regions, the female forty-six ; while the regions common to both are forty-five. The double regions, with the exception of the XIII. belong to the extremities and the lateral as* pects of the head and trunk ; the single regions ta the glabellar and inial aspects of the head, and to the sternal and dorsal of the trunk : these last ex- tending, however, dextrad and sinistrad of the me- sial plane, and containing muscles of the same kind on each side, there is in general, through the whole Table, but one half of the muscles enu-> merated in either the double or the single regions. The exceptions of Albinus are the Epicranius Azygus uvulae Diaphragma Constrictor cunni Sphincteres ani Orbicularis oris Arytasnoideus transversals Yet the dextral and sinistral parts of the Epicraiii* tis have very often a separate action, and may fairly be considered as different muscles, although uni- ted at the mesial plane without any marked Hoe of distinction. In some instances a line may be traced between the dextral and sinistral halves of the Azygus uvulx and this line, exactly in th course of the mesial plane, which also divides into similar parts, dextrad and sinistrad* the Diaphragma, Con- KEGIONS OF ALBINUS. 15 stricter cunni, Sphincteres ani, and Orbicularis oris. For though some anatomists have divided the last into two semiorbicular muscles, assigning one to the coronal and the other to the basilar lip ; yet nature has chosen to divide it otherwise, placing the halves on the two sides, and forming their union at the mesial line, as is evident from hemi- plegia and hair-lip. The only pair that is. not divided by the mesial plane, or between whose halves the mesial plane is not interposed, is the two Arytaenoidei obliqui ; and the only muscle which crosses that plane, and is not naturally distinguished into halves, is the Arytaenoideus transversus. But among the muscles which are reckoned in pairs, there are several groups on one side which have corresponding groups on the other, and where each group is considered as forming but one muscle. Among these groups are the Constric tores pharyngis superiores Constrictores pharyngis medii Constrictores pharyngis inferiores Interspinales cervicis Interspinales dorsi Interspinales lumborurn Intertransversarii priores colli Intertransversarii posteriores colli Intertransversarii dorsi Intertransversarii lumborum 18 REGIONS GF ALBINUS. Levatores costarum breviores Levatores costarum longiores Intercostales externi Intercostales interni Lumbricales manuum Lumbricales pedum and a great many more. Even various muscles, that in their appearance have not the most distant analogy to groups, are composed of parts that have different attachments, and that act as separate independent muscles. The common flexors of the toes and fingers are muscles of this kind. The fibres of these have similar origins but different insertions : the fibres of others, as the Pectoralis, have different origins but a similar insertion : while a third kind, as the Trapezius, have different origins and different in- sertions. The groups and muscles of one side, that have groups and muscles corresponding on the other, are, according to Albinus, about two hundred and thirty-two ; not including the Arytaenoidei obliqui, nor the halves of muscles that are divided by the mesial line. Yet, besides excluding from this enumeration the muscles of the .heart, the stomach, intestines, and urinary bladder, he has also excluded some of the muscles that are pictured in his tables, as the REGIONS OF ALBINUS* 17 ciliaris* and the thyreo-epiglotticus major and mi- nor\ ; avoiding, though not always, those trifling distinctions that distract the attention, and unne- cessarily multiply the number of muscles. The making of more trifling distinctions, the notice of several lusus naturae, and collections of facts equally unimportant, which he has despised, remain to be the objects of modern discovery, and may, if we choose, be made a pretence for accusing him of neglect or inaccuracy ; be made the means of impressing the public with a favourable idea of our own patience, acuteness, and diligence ; and the means, at the same time, of establishing for ourselves a temporary reputation with the hunters of novelties that swarm among the thoughtless, il- literate, and vulgar. * Albin. Tab. Musctil. XI. fig. 2. a, I, c, d t e. f Albin. Tab. Muscul. XII, fig. 3. fjg t b\ fig. 7. a t I, c ; ft fig. 3. i, k, I. B REGIONS into which the Musdes are arranged according to INNES* I. Muscles of the Teguments of the Cranium* Occipito-frontalis Corrugator supcrcilii II. Muscles of the Ear. 1, Common AttoIIens aurem Anterior auris Retrahentes auris 2* Proper Helicis major Helicis minor Tragicus Antitragicus Transversus auris 3. Internal Laxator tympani Tensor tympani Stapedius III. Muscles of the Eyelids. Orblcularis palpebrarum Levator palpebrae superioris 6 REGIONS OF INNES. 19 IV. Muscles of the Eyeball. 1. Straight Levator oculi Depressor oculi Adductor oculi Abductor oculi 2. Oblique Obliquus superior, seu Trochlearis Obliquus inferior V. Muscle of the Nose. Compressor naris \ VI. Muscles of the Mouth and Lips* 1. Above Levator anguli oris Levator labii superioris alseque nasi Depressor labii superioris alaeque nasi 2. Below Depressor anguli oris Depressor labii inferioris Levator labii inferioris 3. Outward Buccinator Zygomaticus major Zygomaticus minor 4. Common Orbicularis oris B 2 20 REGIONS OF INN&S. VII. Muscles oftJie Lower Jaw. Temporalis Masseter Pterygoideus internus Pterygoideus externus VHI, Muscles which appear about the anterior part of the Neck Musculus cutaneus, vulgo Platysma my- oides Sterno-cleido mastoideus IX. Muscles situated between the Lower yaw and Os Hyoides. 1. Before Digastricus Mylo-hyoideus Genio-hyoideus Genio-hyo-glossus 2. At the side Hyo-glossus Lingualis X. Muscles situated between the Os Hyoidef and Trunk. FIRST LAYER Sterno-hyoideus Omo-hyoideus REGIONS OF 1NNES. 21 SECOND LAYER Sterno-thyroideus Thyreo-hyoideus Crico-thyroideus XI. Muscles situated between the Lower Jarw and Os Hyoides laterally. Stylo-glossus Stylo-hyoideus Stylo-pharyngeus Circumflexus, seu Tensor palati Levator palati XII. Muscles situated about the entry to the Fauces. 1. On the side Constrictor isthmi faucium Palato-pharyngeus 2. In the middle Azygos uvulae XIII. Muscles situated on the posterior part of the Pharynx. Constructor pharyngis inferior Constrictor pharyngis medius Constrictor pharyngis superior XIV. Muscles situated about the Glottis. Crico-aryteenoideus posticus Crico-arytcEnoideus lateralis Thyreo-arytenoideus 22 REGIONS OF INNES, Arytaenoicleus obliquus Aryfr*:noideus transversus Thyreo-epiglottideus Arytaeno-epiglottideus XV. Muscles situated on the anterior part of th Abdomen. Obliquus descendens externus Obliquus ascendens internus Transversalis Rectus abdominis Pyramidalis XVI. Muscles about the Male Organs of Generation. 1. Testes Dartos Cremaster 2. Penis Erector penis Accelerator urinae, seu Ejaculator se minis Transversus perinaei Transversus perinaei alter XVII. Muscles of the Anus. Sphincter ani Levator ani XVIII. Muscles of the Female Organs of Generation. Erector Clitoridis Sphincter Vaginae REGIONS OF INNES. 2$ XIX. Muscles situated within the Pelvis. Obturator internus Coccygeus XX. Muscles situated within the Cavity of the Abdo- men. Diaphragma Quadratus lumborum Psoas parvus Psoas magnus* Iliacus internus*" XXI. Muscles situated on the anterior part of the Thorax, FIRST LAYER Pectoralis major SECOND LAYER Subclavius Pectoralis minor Serratus magnus XXII. Muscles situated between t/ie Ribs and within the Thorax, Intercoslales externi Intcrcostales interni Triangularis, seu Sterno-costalis * See Reg. XXIX. 24 REGIONS OF INNES. XXIII. Muscles situated on the anterior part of the Neck, close to the Vertebra. Longus colli Rectus capitis interims major Rectus capitis interims minor Rectus capitis lateralis XXIV. Muscles situated on the posterior part of the Trunk, FIRST LAYER Trapezius, seu Cucullaris Latissimus dorsi SECOND LAYER 1. On the back Serratus posticus inferior Rhomboideus major et minor 2. On the neck Splenius capitis et colli 3. Single pair Serratus superior posticus THIRD LAYER % 1. On the back Spinalis dorsi Longissimus dorsi Sacro-lumbalis 2. On the neck Complexus Trac helo-mastoideus Levator scapulae REGIONS OF INNES. 125 FOURTH LAYER 1. On the back Semispinalis dorsi Multifidus spinae 2. Posterior part of the neck Semispinalis colli Transversalis colli 3. Below the posterior part of the occiput Rectus capitis posticus major Rectus capitis posticus minor Obliquus capitis superior Obliquus capitis inferior 4. On the side of the neck Scalenus anticus Scalenus medius Scalenus posticus 5. Between the spinous and transverse pro- cesses of contiguous vertebras Interspinales colli Intertransversales colli Interspinales dorsi et lumber um Intertransversales dorsi Intertransversales lumborum XXV. Muscles of the Superior Extremities* On the scapula 1. Behind Supra-spinatus Infra-spinatus Teres minor ^ REGIONS OF INNES. 2. Along the inferior costa of the scapula Teres major 3. Before the scapula Deltoides Coraco-brachialis 4. Beneath the scapula Subscapularis XXVI. Muscles situated on the Os Humeri, 1. Before Biceps flexor cubiti Brachialis internus 2, Behind Triceps extensor cubiti Anconeus XXVII. Muscles situated on the Cubit or Fore-anti FIRST CLASS Flexors and extensors of the whole hand 1. Flexors Palmaris longus Palmaris brevis Flexor carpi radialis Flexor carpi ulnaris 2. Extensors Extensor carpi radialis longior Extensor carpi radialis brevidr Extensor carpi ulnaris REGIONS OF INNES, 27 SECOND CLASS Flexors and extensors of the fingers 1. Flexors Flexor sublimis perforatus Flexor profundus perforans Lumbricales 2. Extensors Extensor digitorum communis THIRD CLASS Supinators and pronators, or those that roll the radius on the ulna 1. Supinators Supinator radii longus Supinator radii brevis 2, Pronators Pronator radii teres Pronator radii quadratus XXVIII. Muscles situated on the Hand chiefly. 1. Muscles of the thumb Flexors Flexor longus pollicis manus Flexor brevis pollicis mamis Flexor ossis metacarpi pollicis, seu Oppo- nens pollicis Extensors Extensor ossis metacarpi pollicis manus Extensor primi internadii Extensor secundi internadii 28 REGIONS OF INNES, Abductor pollicis manus Adductor pollicis manus 2. Muscles of the fore-finger Indicator Abductor indicis manus 3. Muscles of the little finger Abductor minimi digiti manus Adductor metacarpi minimi digiti manus Flexor parvus minimi digiti 4. Muscles between the metacarpal bones Interossei interni, viz. Prior indicis Posterior indicis Prior annularis Interosseus auricularis Interossei externi, seu bicipitcs, viz. Prior medii Posterior medii Posterior annularis XXIX. Muscles of the Inferior Extremities. Muscles on the outside of the pelvis, which are called muscles of the thigh 1. Before Psoas magnus* Iliacus internus* Pectinalis See Reg. XX. REGIONS OF INNES, 3< Triceps adductor femoris, comprehend ing Adductor longus femoris Adductor brevis femoris Adductor magnus femoris Obturator externus 2. Behind FIRST LAYER Gluteus maximus SECOND LAYER Gluteus medius THIRD LAYER Gluteus minimus Pyriformis Gemini Quadratus femoris XXX. Muscles situated on the Thigh, ~ ., 1. Outside Tensor vaginae femoris 2. Inside Sartorius Gracilis 3. Before Rectus Vastus externus Vastus internus Cruralis 4. Behind Semitendinosus 6 fcfcGIONS OF INNE5* Semimembranosus Biceps flexor cruris Popliteus XXXI. Muscles situated on the Leg. FIRST CLASS Extensors and flexors of the foot 1. Extensors Gastrocnemius externus, sen Gemellus Soleus, seu Gastrocnemius intern us Plantaris 2. Flexors Tibialis anticus Tibialis posiicus Peroneus longus Peroneus brevis SECOND CLASS Common extensors and flexors of the toes 1 Common extensors Extensor longus digitorum pedis Extensor brevis digitorum pedis 3. Flexors Flexor brevis digitorum pedis, seu Su- blimis perforatus Flexor longus digitorum pedis, seu Pro- fundus perforans iTlexor digitorum accessorius, seu massa carnea Jacobi Sylvii Lumbricales pedis o REGIONS OF INNES. 1 XXXII. Muscles 'which are chiefly situated on the Foot. 1. Muscles of the great toe Extensor proprius pollicis pedis Flexor longus pollicis pedis Flexor brevis pollicis pedis Abductor pollicis pedis Adductor pollicis pedis 2. Muscles of the little toe Abductor minimi digiti pedis Flexor brevis minimi digiti pedis 3. Muscles from the metatarsal bones Interossei pedis extern! Bicipites, viz. Abductor indicis pedis Adductor indicis pedis Adductor medii digiti pedis Adductor tertii digitii pedis Interossei pedis interni, viz. Abductor medii digiti pedis Abductor tertii digiti pedis Abductor minimi digiti pedis 4. Transversalis pedis 32 REGIONS OF 1NNES, In the Second Book of Historic Musculorum^ Albinus, following the same order that he has ob- served in numbering the regions, has described the relative situations of the muscles as they pre- sent themselves on dissection ; while Innes, with more conciseness and method, and with more per- spicuity, though not with the same accurate mi- nuteness, has endeavoured to communicate the like information, by subdividing many of his re- gions, and classing his muscles according to their layers. His description of the muscles, in which he first mentions their origin, then their insertion, and at last their uses, is agreeable to the plan of the celebrated Douglas. This plan, with respect to perspicuity, has many advantages, although it must lead to erroneous conclusions, if the student infer that the origin is always the fixed point, and the insertion al- \vays the moveable; for sometimes the one, and sometimes the other, is the moveable point, al- though the insertion in ordinary cases be more frequently so than the origin. It tends likewise to promote error, by directing the attention chiefly to the opposite extremities of a muscle, and by di- verting it from those connections which muscles frequently form in their course with those in their vicinity. Winslow therefore, who dislikes this dis- tinction into origins and insertions, includes both tinder the general name of attachments. The attachments of muscles at their extremities, REGIONS OF INNES. 33 which are those principally mentioned by Innes, are in most instances conformable to what were ob- served by Albinus ; and this correctness in point of fact, so far as he goes, with his clearness of me- thod and conciseness of description, has rendered his work one of the most popular, convenient, and useful, that has yet been published, for the purposes of dissection. c REGIONS into wMch the Muscles art arranged according to DUMAS. L Region Epicranienne, ou du Crane. Occipdto-frontal II. Front ale, ou du Front. Fronto-sourcilliet Cutaneo-sourcillier III. Palpebmle, ou des Paupieres* Maxillo-palpebral Orbito-sus-palpebra! IV. Orbitaire^ ou des Orbites* Optico-trochlei-sclerotlciea Maxillo-scleroticien Sus-optico-spheni-scleroticien Sous-opti-spheno-scleroticien Orbito-intus-scleroticien Orbito-extus-scleroticien V, Auriculaire Extern?, ou des Temporo-conchinien Xigomato-conchin iem .REGIONS OF DUMAS. $ Mastoido-conchini n Antheli-tragique Concho-tragique Helix Concho-helix Concho-anthelix VI. Auriculaire Interne, ou de I'Ouie. Salpingo-malleen Spheni-salpingo-malleen Acoustico-malleen Pyramido-stapedicn VII. Malaire, ou Laterale de la Face. Arcadi-temporo-maxillairo Zigomato-maxillaire Alveolo-maxillaire VIII. Nasale, ou du Nez. Maxillo-labii-nasal Maxillo-alveoli-nasai Fronto-nasal Maxillo-narinal IX. Labiate, ou des Levres. Orbito-maxilli-labial Sus-maxillo-labial Naso-labial Labial Sous-maxillo-labial 36 REGIONS Sterno-mastoideus 5 Sterno-cleido-mastoideus Sterno-clavio-mastoidien 8 8 12 Coccygeus Ischio-coccygien 18 IQ 28 Complexus Dorsi-tracheli-occipital IQ 24 25 Compressor naris Maxillo-narinal 358 Compressor prostatae 18 Constrictor cunni Sphincter vaginae Anulo-syndesmo-clitoridien. 17 18 32 ' Constrictor inferior pharyngis Crico-thyro-pharyngien 8 13 17 Constrictor medius pharyngis Hyo-glosso-basi-pharyngien 8 13 17 Constrictor superior pharyngis Pterigo-syndesmo-staphili-pharyn- gien..... 8 13 17 Constrictor isthmi faucium Glosso-staphilin 8 12 15 Goraco-brachialis Coraco-humeral 23 25 33 ALBINUS, INNES, AND DUMAS. 55 Coraco-hyoideus AL. IN. DU. Omo-hyoideus Scapulo-hyoidien 8 10 13 Corrugator supercilii Cutaneo-sourcillier , 312 Cremaster . 13 16 Crico-arytaenoideus lateralis Crico-lateri-arithenoidien 8 14 14 Crico-arytaenoideus posticus Crico-crcti-aritheno'idierw 8 14 14 Crico-thyreoideus Crico-thyroidien 8 10 14 Cruralis* 27 30 CuculJaris Trapezius Occipiti-dorso-clavi-sus-acromien 19 24 23 D Deltoides Sous-acromio-clavi-humeral 22 25 33 Depressor alae nasi Depressor labii superioris alaeque nasi Maxillo-alveoli-nasal ,.., 368 Depressor anguli oris Sous-maxillo-labial 3 6 9 Depressor labii inferioris Mefctonier labial 3 6 11 Vide Tri-fcjmoro-tibi-rotulien, Dumas XLI. 56 SYNONYMS OF Diaphragma AL. IN. Dtf. Thoraco-abdominal 14 20 22 E Epicranius Occipito-frontalis Occipito-frontal Fronto-sourcillier Ill Erector clitoridis Ischio-clitoridien 17 18 32 Erector penis Ischio-eaverneux 17 16 32 Extensor brevis digitorum pedis Calcaneo-sus-phalangettien com- mun 29 31 46 Extensor communis digitorum manus Epicondylo-sus-phalangettien com- mun 24 2? 37 Extensor longus digitorum pedis Peroneo-tibi-sus-phalangettiencom- mun 28 31 44 Extensor major pollicis manus Extensor secundi internodii Cubito-sus-phalangettien du pouce 24 28 37 Extensor minor pollicis manus Extensor primi internodii Cubito-sus-phalangien du ppuce..i24 28 37 Extensor proprius digiti auricularis, seu extensor proprius digiti minimi manus ALBINUS, INNES, ANfr DUMAS. 5? Epicondylo-sus-phalangettien du AL. IN. DU. petit doigt 24 37 Extensor propius pollicis pedis Peroneo-sus-phalanginien du pouce 28 32 44 Extern us mallei Laxator tympani Spheni-salpingo-malleen .....,,. 726 Flexor brevis digit! minimi pedis Metatarso-phalangien du petit doigt 30 32 47 ' Flexor brevis digitorum pedis Flexor brevis digitorum pedis, sub- limis perforatus Calcaneo-phalanginien commun 30 31 47 Flexor brevis pollicis manus Carpo-phalanginien du pouce 25 28 33 Flexor brevis pollicis pedis Tarso-phalangien du pouce 30 32 47 Flexor longus digitorum pedis Flexor longus digitorum pedis pro- fundus perforans Tibio-phalangettien commun 28 31 45 Flexor longus pollicis manus Radio-phalangettien du pouce 24 28 35 Flexor longus pollicis pedis Peroneo-phalanginien du gros orteil 28 32 45 Flexor parvus digiti minimi manus Second carpo-phalangien du pe- tit doigt 25 28 38 58 SYNONYMS OF G Gemellus AL. IN. DU. Gastrocnemius externus, seu Ge- mellus Bi-femoro-calcanien 28 31 45 Gemini Ischio-spini trochanterien 26 29 29 Genio-glossus Genio-hyo-glossus Genio-glosse 8 9 16 Genio hyoideus Genio-hyoidien 8 9 13 Glutens magnus Gluteus maximus Ilii-sacro-femoral 26 29 29 Gluteus medius Ilio-trochanterien 26 29 29 Gluteus minor Gluteus minimus Ilio-ischii trochanterien 36 29 29 Gracilis Sous-pubio-creti-tibial 27 30 42 H Hyo-thyreoideus Thyreo-hyoideus Hyo-thyroidien 8 10 13 I Jliacus internus Illiaco-trochantin 16 29 30 ALBINUS, INNES, AND DUMAS. 50 Indicator AL. IK. DU. Gubito-sus-phalangettien de 1'index 34 28 37 Infra-spinatus Sous-spini-scapulo-trochiterien 22 25 33 Intercostales extern! Inter-lateri*costaux , 20 22 19 Intercostales interni Inter-pleuri-costaux.* 20 2 20 Interossei extern! digitorum. manus Interossei externi, seu bicipites Sus-metacarpo-lateri-phalangiens 25 28 39 Interrossei externi digitorum pedis Interrossei pedis externi, seu bici- pites Sus-metatarso-lateri-phalangiens... 30 32 46 Interossei interni digitorum manus Sous-metacarpo-lateri*phalangiens 25 28 38 Interossei interni digitorum pedis Sous-metatarso-lateri-phalangiens 30 3& 47 Interspinales cervicis Interspinales colli Interepineux 19 24 20 Interspinales dorsi Lumbo-dorso-spinal 19 26 Interspinales lumborum 19 24 Intertransversarii dorsi Intertransversales dorsi 19 24 Intertransversarii lumborum Intertransversales lumborum ..... 19 24 Intertransversarii posteriores colli Intertransversarii priores colli 6'0 SYNONYMS OP Intertransversales colli AL. IN. bth Intertransversaires 21 24 26 L Latissimus colli Musculus cutaneus, vulgo platysma myoides Thoraco-maxilli-facial .*... 8 8 12 Latissimus dorsi Dorsi-lumbo-sacro-humeral...* 19 24 24 Laxator tympani Acoustico-malleen 7 6 Levator anguli oris Sus maxillolabial 369 Levator ani Pubio-coccigi-annulaire 18 17 30 Levatores breviores costarum Levatores longiores costarum Smvcostaux ig 20 Levator labii superioris Levator labii superioris alaeque nasi Orbito-maxilli-labial 369 Levator menti Levator labii inferioris Sous-maxillo-cutane 3 6 11 Levator palati mollis Levator palati Petro-salpingo-staphilin 8 11 15 Levator palpebrae superioris Orbito-sus-palpebral 533 ALBINUS, INNES, AND DUMAS. 6l Levator scapulae AL. IN. DU. Trachelo-anguli-scapulaire 19 24 23 Lingualis Lingual 8 9 16 Longissimus dorsi Lumbo-dorso-trachelien 19 24 26 Longus colli Pre-dorso-cervical 21 23 27 Lumbricales manus Annul! tendino-phalangiens 25 27 38 Lumbricales pedis Planti-tendino-phalangiens 30 31 47 M Major helicis Helix 625 Minor helicis Concho-helix 625 Masseter Zigomato-maxillaire 4 7 7 Multifidus spinae Transverso-spinal 19 24 46 Mylo-hyoideus Mylo-hyo'idien 8 9 13 N Nasalis labii superioris Naso-labial. ( 3 9 6 SfNONYMS OF o Obliquus externus abdominis AL. IN. DU. Obliquus desceadens externus Ilio-pubi-costo-abdominal .... 12 15 21 Obliquus inferior capitis Spiru-axoido-tracheli-atloidien IQ 24 25 Obliquus inferior oculi Maxillo-scleroticien % 5 4 4' Obliquus internus abdominis Obliquus ascendens internus Ilio-lumbo-costi -abdominal 12 15 21 Obliquus superior capitis Trachelo-atloi'do-occipital IQ 24 25 Obliquus superior oculi Obliquus superior oculi, seu troch- learis Optico-trochlei-scleroticien 5 4 4 Obturator externus Extra-pelvio-pubi-trocbanteriea 27 29 41 Obturator internus Intra-pelvio-trochanterien 26 19 29 Opponens pollicis manus Flexor ossis metacarpi pollicis, seu opponens pollicis Carpo-phalangien du pouce 25 28 38 Orbicularis oris Labial 369 Orbicularis palpebrarum Maxillo-palpebral 333 ALBINUS, INNES, AND DUMAS. 63 P Palato-pharyngeus AL. IN. DU. Palato-pharyngien 8 J2 15 Palmaris brevis Palmaire cutane , 25 27 38 Palmaris longus Epitrochlo-carpi-palmaire 24 27 36 Pectineus Pectinalis Pubio-femoral ... 27 29 41 Pectoralis Pectoralis major Sterno-costo-clavio-humeral 10 21 18 Peroneus brevis Petit peroneo.sus-metatarsien 28 31 44 Peroneus longus Tibi-peroneo-tarsien 28 31 44 Peroneus tertius Grand peroneo-sus-metatarsien 28 31 44 Plantaris Petit femoro-calcanien 28 31 45 Popliteus Femoro-popliti-tibial .. 28 30 45 Profundus Flexor profundus perforans Cubito-phalangettien commun 24 27 36 Pronator quadratus Pronator radii quadratus Cubito-radial 24 27^36 64 SYNONYMS OF Pronator teres Pronator radii teres AL. IN. DU. Epitrochlo-radial 24 2736 Psoas magnus Pre-lumbo-trochantin .16 29 27 Psoas parvus Pre-lumbo-pubien 16 20 27 Pterygoideus externus Pterigo-colli-maxillaire Q 7 10 Pterygoideus interims Pterigo-anguli-rnaxillaire 9 7 10 Pyramidalis Pubio-ombilical 12 15 21 Pyriformis Sacro-ili-trochaiUerien 26 29 29 Q Quadratus femoris Tuber-ischio-trochanterien 26 29 29 Quadratus lumborum Ilio-lumbi-costal 16 20 2S R Radialis externus brevior Extensor carpi radialis brevior Epicondylo-sus-metacarpien 24 27 37 Radialis externus longior Extensor carpi radialis longior Humero-sus-metacarpien 24 27 37 AtBINUS, INNES, AND DUMAS. 65 Radialis internus AL. IN. DU. Flexor carpi radialis Epitrochlo-metacarpien . 24 27 3 Rectus abdominis Pubio-stemal ....... ...;. 12 15 21 feectus abducens oculi Abductor oculi Orbito-extus-scleroticien 5 4 4 Rectus adducens oculi Adductor oculi Orbito-iritus-scleroticien 5 4 4 Rectus attollens oculi Levator oculi Sus-optico-spheni-scleroticien ...*,. 5 4 4 Rectus deprimens oculi Depressor oculi Sous-opti-spheno-scleroticien * 54 4 Rectus cruris Rectus Ilio-rotulien *. 27 30 41 Rectus internus major capitis Grand trachelo-basilaire 21 23 27 Rectus internus minor capitis Petit trachelo-basilaire 21 23 27 Rectus lateralis capitis Trachelo-atloido-basilaire 21 23 27 Rectus posicus major capitis Spim-axoi'do-occipital 19 24 25 Rectus posticus minor capitis Tuber-attoi'do-occipital 19 24 55 E 66 SYNONYMS OF Retrahentes auriculae AL. IN. DU, Mastoido-conchinien ............... 2 2 5 Rhomboideus major ^ Rhomboideus minor 5 Cervici-dorso-scapulaire 19 24 23 S Sacro-lumbalis Lumbo-costo-trachelien 19 24 26 Salpingo-pharyngeus Petro-salpingo-spheno-pharyngien 8 17 Sartorius Ilio-creti-tibial 27 30 41 Scalenus medius Scalenus posticus Scalenus prior Scalenus anticus Trachelo-costal 21 24 2$ .Semimembranosus Ischio-popliti-tibial 27 30 43 Semispinalis dorsi Trans verso*spinal 19 24 26 Semitendinosus Ischio-crctUibial 27 30 43 Serratus anticus Pectoralis minor Costo-coracoi'dien ...*....... 10 21 18 Serratus magnus Costo-basi-scapulairc 11 21 19 ALBINUS, INNES, AND DUMAS. 67 Serratus posticus inferior AL. IN. DU. Dorsi-lumbo-costal 19 24 24 Serratus posticus superior Cervici-dorso-costal ig 24 23 Soleus Soleus, seu gastrocnemius internus Tibio-peronei-calcanien 28 31 45 Sphincter ani externus Sphincter ani Coccigio-cutane-sphincter 18 17 31 Sphincter ani internus Recto-cutane-sphincter , 18 31 Spinalis cervicis Semispinalis colli Transverse-spinal ,. 19 24 26 Spinalis dorsi Lumbo-dorso-spinal .. 19 24 26 Splenius capitis Cervico-dorsi-mastoidien -j Splenius colli Dorso-trachelien Splenius Stapedius Pyramido-stapedien ,,.. 7 2 6 Sterno-hyoideus Sterno-hyoidien 8 10 13 Sterno-mastoideus Vid cleido-mastoideus ..... 8 8 12 Sterno-thyreoideus Sterno-thyroidien 8 10 13 68 SYNONYMS Otf Stylo-glossus AL. IN. D& Stylo-glosse 8 31 16 Stylo-hyoideus Stylo- hyoi'dien 8 11 13 Stylo-hyoideus alter 8 Stylo-pharyngeus Stylo-thyro-pharyngien 8 11 17 Subclavius Costo-claviculaire ^ 10 21 18 Sublimis Flexor sublimis perfbratus Epitrochlo-coroni-phalanginien *.. 24 27 36 Subscapularis Sous-scapulo-trochinien ............ 22 25 33 Supinator brevis Supinator radii brevis Epicondylo-radial 24 27 37 Supinator longus Supinator radii longus Humero-sus-radial 24 27 37 Supraspinatus Sus-spini-scapulo-trochiterien ... 22 25 33 Temporalis Arcadi-temporo.maxillaire 4 7 7 Tensor tympani Salpingo-malleen 726 Tensor vaginae femoris Ilio-aponeurosi-femoral 27 30 40 ALBINUS, INNES, AND I>UMAS. 6<) Teres major AL. IN. DU. Anguli-scapulo-humeral 22 25 33 Teres minor Margini-sus-scapulo-trochiterien 22 25 33 Thyreo-arytaenoideus . Thyro-arithenoidien 8 14 14 Thyreo-arytaenoideus alter minor 8 Thy reo- cpiglottideus Thyro-epiglotique 14 14 Tibialis anticus Tibio-sus-metatarsien ....*. 28 31 44 Tibialis posticus Tibio-tarsien 28 31 4i Trachelo-mastoideus Trachelo-mastoidien ............... 19 24 25 Tragicus Concho-tragique 6 2 5 Transversalis cervicis Transversalis colli 1Q 24 Transversus abdominis Transversalis Lumbo-ili- abdominal 12 15 21 Transversus auriculae Concho-anthelix 6 2 5 Transversus perinci Ischio-pubi-prostatique 18 16 32 Transversus perinei alter Ischio-pubi-prostatique ...,. 18 16 32 70 SYNONYMS OF ALBJNUS, &C. Triangularis sterni AL. IN. DU. Triangularis, seu sterno-costalis Sterno-costal 15 22 20 Triceps brachii Triceps extensor cubiti Tri-scapulo-humero-olecranien 23 26 35 V Vastus externus Cruralis tTri-femoro-tibi-rotulien Vastus interims ITri-i U Ulnaris externus Extensor carpi ulnaris Epicondy-cubito.sus-metacarpien 24 27 37 Ulnaris internus Flexor carpi ulnaris Epitrochli-cubito-carpien .. 24 27 S5 Zygomaticus major Grand zigomato-labial 3 6 9 Zygomaticus minor Petit zigomato-labial 3 6 SYNONYMS PRIOR TO THE TIME OF ALBINUS. ALBINUS, with great learning and industry, has published these synonyms in his Third Book of Historia Musculorum. The principal authors whom he has quoted are here arranged in the order of time ; and the reason why earlier writers than Vesalius are seldom referred to, is, that Vesalius was among the last, and decidedly the greatest, of the anatomists who were accustomed to distinguish the muscles by descriptions and numbers, rather than by names. This table will be useful as a key to most of the writers who have treated of myology, from the middle of the sixteenth to nearly the middle of the eighteenth century, that is, from the time of Ve- salius to Albinus ; and should the reader peruse it with attention, he will perceive many of the dif- ficulties with which anatomists had to contend in improving this part of their science, and be made sensible of many obligations that are laid upon him to speak of their errors with lenity and in- dulgence, and to mention their names with grati- tude and respect. SYNONYMS The Names of these Authors, with the Periods at which tJiey began to flourish. Sylv. Ves. Valverd. Col. Fal. Eust. Colter. Arant. Laur. Cas. Fabric. Riol. Spig. Bucret. T. Earth. Vesling. Drake Diemer. High. Pecquet Sylvius . . . Vesalius . . Valverda. . Columbus . Fallopiua . Eustachius Coiterus . . Arantius . Laurentius Casserius . Fabric ius . Riolanus . . Spigelius . Bucretius . T. Bartholi Veslingius. Drake . . . 1539 543 .1556 '559 . 1561 1563 . 1566 '595 1595 . 1600 . 1602 .. 1607 , 1626 . 1627 ne 1641 . . 1641 . 16/1 1 DC Mar. Lower De Graaf Molin. Steno Du Ver. C. Earth. Dionis Vieus. Verheyen Cowp. Littre Valsalv. Sant. Morg. Doug. Heist. Win. Senac Monro De Marchett 1652 De Graaf... 1668 Molinetti . . . 1 669 Du Verney 1675 C. Bartholine 1675 Dionis . . . - - 168* Vieusseniu Verheyen Cowper . Littre . . Valsalva . Santorini. Morgagni Douglas . Heister . . Winslow. Senac. . . Monro . . i 1684 ..1693 . 1694. . 1700 .1704 . 1705 . 1706 .1707 .1711 .1719 .1724 1733 Diemerbroek 1649 Highmore . . 1651 Pecquet .... 1651 Abductor brevis pollicis manus Qui pollicem maxime abducit, Fes. Septimus extremae manus musculus, Col. Septimus, Fal. Pars thenaris, Riol. Abducens pollicem, Spig. Abductor pollicis, Cowp. Doug. Pars ejus qui le thenar, Win. Abductor digiti minimi manus Vigesimus manus digitos moventium, Sextus extremae manus musculus, Col. PRIOR TO ALBINUS. ^3 Pars hypothenaris parvi digiti, RioL Minimum digitum abducens, Spig . Pars abductoris minimi digiti, Gawp. Extensor tertii internodii minimi digiti, Doug* L'hypothenar du petit doigt, Win. Abductor digiti minimi pedis Decimus septimus pedis digitos moventium, Ves. Tertius musculus digitis pedis inserviens, Col. Parvus musculus ad latus minimi, FaL Musculus minimo digito abducendo dicatus, Cas. Abductor minimi digiti, RioL Cowp. Doug. Minimum abducens, Spig. Le metatarsi en, una cum eo qui le grand pa- rathenar, Win. Abductor indicis manus Alter musculus, lateralibus pollicis motibus in- serviens, Ves. Septimus pollicis musculus, O?/. Primus, Fa!. Abductor indicis, Riol. Doug. Adducens pollicem, Spig ... Adductor pollicis, Cowp. Le demi-interosseux de Pindex, Win.. Abductor longus pollicis manus Vigesimus-secundus digitos moventium, una cum vigesimi-tertii portione, cujus tendo in primi pollicis ossis radicem implanutur, 14 SYNONYMS Quinti manus exterioris musculi, Col. pars quae ad primum pollicis articulum proce- eh't, una cum ea quas ad os brachialis, quo pollex sulcitur. Secundi et tertii pollicis internodii extensoris, Spig. superior portio, una cum inferioris portione, cujus tendo radici primi pollicis internodii adnascitur. Extensor primi internodii ossis pollicis, Cowp. Doug. Pars ejus, qui le premier extenseur du pouce, ilia autem, qui s'attache au bord de la base de la premiere phalange, Win. Abductor pollicis pedis Becimus-octavus pedis digitos moventium, Ves. Secundus pedis musculus digitis inserviens, pollicem ab aliis digitis deducens, Col. Parvus musculus ad latus pollicis, Fal. Pollicem adducens, Cas. Spig. Abductor pollicis, RioL Cowp, Doug. Pars ejus qui le*thenar, Win. Accelerator Primus penis musculus, Fes. Col. Laur. Accelerator, Rial. Morg. Sant. Inferior, sive urethram trahens, Spig. Dilatator urethras, sive ar- -ierator seminis et urinse, De Mar. ^Urethram dilatans^ De Graaf. PRIOR TO ALBTNUS. 75 Accelerator urinae, Cowp. Doug* Le Bulbo-caverneux, Win. Adductor brevis femoris Pars quinti femur moventium, Fes. Pars octavi femoris musculi, Col. Secunda pars quinti femur moventium, FaL Alterum caput tricipitis, Riol. Pars flectentium tertii, Splg . Pars tricipitis, Cowp. Adductor femoris secundus, Doug. Le second muscle du triceps, Win. Adductor longus femoris Pars octavi femur moventium, Ves. Fortasse pars septimi femoris musculi, Col. Pars prima quinti femur moventium, Fol* Primum caput tricipitis, Riol. Pars flectentium tertii tricipitis, Spig . Pars tricipitis, Coivp. Adductor femoris primus, Doug. Le premier muscle du triceps, Win. Adductor magnus femoris Pars quinti femur moventium, Fes. Pars octavi femoris musculi, Col. Tertia pars cum quarta quinti moventium fe- mur, Fed. Tertium caput tricipitis, Riol. Pars fiectentiurri tertii, tricipitis, Spig. Pars tricipitis, 'Cowp. Adductor iemoris tertius cum quarto, Doug . Le troisieme muscle du triceps, Win. 7-6 SYNONYMS Adductor ossis tnetacarpi digiti auricularis Illorum octo, qui quatuor subserviunt digitis, parvum digitum flectentium primus, Vies. Unus octo aliorum musculorum, See. Col. Unus illorum octo qui inter ossa metacarpi continentur, Fed. An pars hypothenaris parvi digiti, Riol? Interosseus ultimo ossi metacarpi parte manus externa adhaerens, Spig. Pars abductoris minimi digiti, Gowp. Flexor primi internodii minimi digiti, Doug. L'adducteur oblique du quatrieme os du me- tacarpe, Win. Le metacarpien, Ejusd. Adductor pollicis manus Trium qui securjdo pollicis ossi famulantur primus, Ves. Pars musculi pollicem flectentis volam ver- sus, CoL Secundus, FaL Pars hypothenaris pollicis, RioL Est haud dubie secundi internodii pollicis flexor primus, Spig. Pars flexoris primi et secundi ossis pollicis, Cowp. Adductor(pollicis)ad minimum digitum, Doug. Pars ejus qui le meso-thenar, Win. Adductor pollicis pedis Vide musculos primes articulos flectentes, qui tertium musculum in numero succedunt, Ves. PRIOR TO ALBINUS. 77 i Decem musculos singulis digitis pedis binos inservientes, CoL Parvos musculos quorum quatuor collocan- tur in planta, Fal. An hue pertinent, musculi in pedio ab ipsius ossibus orti, Sylv.? Alius musculus transversus, RioL Interosseus, Spig. Interosseus ad indicem pertingens, Bucreti Adductor pollicis, Cowp. Doug. Pars ejus, qui 1'antithenar, Win* Anconeus Angoneus, RioL Anconaeus, Cowp. Angoneus vel cubitalis, RioL Doug. Le petit ancone, Win. Anterior auriculae Auriculae musculus anterior, Valscdv. L'anterieur, Vieus. Musculus novus conchae proprius, Sant* L'anterieur de 1'oreille, Win. Antitragicus Musculus antitragi, Valsalv. Sant. Arytsenoideus obliquus , ^ An paris crico-arytaenoidis superioris, Ver- heyen ? De quo Morg. quae vero post has locantur,, saepe in plures junctae fasciculos, &c. Arytaenoideus minor, Doug . 78 , SYNONYMS An ad eum pertinet arytaeno-epyglotteus, Pauli* Paris thyro-arytsenoidis obliqui, Sant. una cum ary-epiglottideo. L'arytenoidien croise Le crico-arytenoidien.superieur, An hue etiam pertinet Taryteno-epi- * glotique ? Arytenoideus transversus Propriorum laryngis undecimus ac duodeci- mus, Ves. Musculus extremus laryngis omnium mini- mus, Col. Sextum par a Vesalio, FaL Alii duo, qui ipsius arytenoidis musculi pro- prii censentur, Fabric. Musculus laryngis conjuge desti tutus, Tertius semicircularis, 3 flectens ad latera, sive claudens secundum par, arytaenoideum, Spig. Secundum par arytfcenoides dictum, Vesting. Exile par, quod arytaenoidum proprium dici- tur, D Mar. Arytenoideus, Rlol. C(rwp. De quo Morg. porro in nobis quae earum fibrarum anticae, seu interiores sunt, &-c* Arytaenoideus major, Doug . Ary-arytaenoidis librae .nierioris, L'arytaenoidien transversal, Win* fRIOR TO ALBINUSi 7Q Attollens auriculam Auriculae primus, FaL Primus propriorum auriculae, Cas. Portio musculi frontalis supra crotaphitam ad aurem product! , Riol. Attollens auriculae, Spig . Le premier de Poreille, Du Verney. Attollens auriculam, Cowp. Superior auriculae, Valsalv. Sant. Le premier et le second mitoyen, Vieus. Le superieur de Poreille, Win. Azygus uvulae Sunt de quibus Dionis, la luette est composce de deux petits muscles ronds qui vieiincnt de la cloison du nez. Columellae musculus teres,' Azygos, Palato-staphilinus, Doug. Le muscle de la luette, Littrc. Uvulae azygos Morgagni,' Azygus Morgagni, J Heist * Uvulae azygus, Sant. Les staphylins ou epistaphylins, i Les staphylins ou epistaphylins moyens, j * B Basio-glossus Videtur esse pars tertii et quarti linguae mus- culorum, Ves. Haud dubie pars secundi paris linguae, FaL &0 SYNONYMS Itemque secundi paris propriorum Arant. Et tertii linguae musculofum paris, Cas* Pars basio-glossi, RioL Videtur et pars quinti paris deprimentis, sive cerato-glossi, Spig. Cerato-glossi pars, named bassio-glossus, Doug . Pars cerato-glossi, Morg. Basio-glossus, Coivp. Le basio-glosse, pars ejus qui le hyo-glosse, Win. Biceps brachii Primus flectentium cubitum, praeter carnosam partem interioris principii, &c. Fes. Primus cubitum flectens, vulgo ab Italis dic- tus il pescetto, praeter alterius initii carno- sam partem, Col. Biceps, RioL Cowp. Cubitum flectentium primus, praeter carno- sam portionem in humeri medium inser- tam, Spig. Biceps m#nus, Steno. Biceps internus, Doug . Le biceps du bras, ^ Le biceps ou le coraco-radial, 5 Biceps cruris Quartus tibiam moventium, Ves* Quintus tibiae musculus, CoL Biceps, RioL Cowp. Flectentium tibiam quintus, biceps, Spig. PRIOR TO AIBINUg. 81 Le biceps de Le biceps, Biventer cervicis Secundi pans caput moventium, primus mus- culus, cum secundo, Ves. Pars secundi musculi capitis, Col. , Secundi mo vends caput, Ful. Vide Eustach* de motu cap. qui hos (a recentioribus ana* tomicis ante alios descriptos) sequuntur, &-c. Pars complexi, RioL Cowp. Doug. Primus musculus, cum secundo, trigemini^ aut compositi, Spig. Pars ejus qui le complexus, Win. Biventer maxillae Alterius lateris maxillam moventium quartus^ Maxilla infericiris quartus os aperiens, Col. Quarti maxillae paris, Arant. Digastricus, RioL Doug. Morg. Sant. Alterius paris maxillse, deprimentis biventris, Paris digastrici, sive biventris, Vesting* Digastricus, seu biventer, Cowp. Le digastrique, Win. The digastric, Monro, Med. Ess, Brachialis internus Secundus, seu cubitum. flectentium posterior, Ves. Secundus cubitum flectens, CoL Brachieus internus, RioL Cowp. F &2 SYNONYMS Cubitum flectentium secundus, brachieus vo ] catus> Spig. De Mar. Brachialis internus, Doug. Le brachial, Win. Buccinator Buccarum, labrorum, et nasi alarum, secun- dus alterius lateris, Ves. Musculus buccae, CoL Bucco, RioL Contrahens conamunis buccarum labiorum- que, Spig. Buccinator, Coivp. Doug. Sant. Le buccinatcur, Win* G Gerato-glossus Videtur esse pars tertii et quarti linguae mus j culorum, Ves. Secundi pans linguae, Fal. Secundi paris propriorum linguae, Araat* Tertii linguae musculorum paris, Cos. Pars basioglossi, Rial. Est quinti paris, deprimentis, sire cerato- glossi, Spig. Cerato-glossus, Cowp. Cerato-glossi pars, qua properly the cerato- glossus, Doug . Pars cerato-glossi, Morg. Le kerato-glosse, pars ejus qui le hyo-glosse, Win. TO* AiJlNUS. 63 Ad hunc quoque, aut potius fortasse ad ba- sio-glossunij pertkiet k chcndro-glosse E- jusd. Ciervicalis descendens Secundi paris dorsi niusculorum secuhduiii principium a costa, Fal. Pars superior cervicalis descendentis, Dinner* Sacrolumbalis pars superior^ Cowp. Cervicalis descendens Diemer. Doug . Sacrolumbi ea superior pars, quam Diemer- brockius cervicalem descendentem muscu^- lurn vocat, Morg. Le transversake grele, ou trans versaire col- lateral du col, Win. Chondro-glossus Paris chondrb-giossi, vel ceratio-glossi, Latine corniculo-lingualis Verheyen. Fortasse et cjiondro^glosstis, Vd-safa. An chondro-glossus, Doug, ? in- cerato-glosso Circumflexus palati mollis Primi paris musculorum, qu, faucibtis dila^. tandis aut constringendis inserviunt, FaL Ptery-staphylinus externus, Rwl. Primi paris dilatantis fauces, quod aliquibuS sphaeno-pharyngeum dicituf, Spig. Paris pterygo-staphylini externi, De Maf. Pterigo palatinus, sen spha^no^pte- ] rigo-palatinus j* Co-wp. Pterigo-staphylinus Novus tubae Eustachiance musculus, l r ithah\ F 2 84 SYNONYMS Musculus tubae novus, Valsalv. vel palato- salpingasus, Doug. Fterigo-staphylinus, Drake. Pterigo-palatinus, Morg. Musculus tubae novus, Sant. Le spheno-salpingo-staphylin, Win. Pars ejus quae pertinet ad palatum est le spheno-staphylin, et le spheno-salpingo- staphylin, ou salpingo-staphylin externe, Win. ad quern pertinet le pterigo-staphylin superieur Pars quae ad processum pterigoideum, est le pterigo-salpingoidien, Win. Cleidomastoideus Musculi a pectoris osse et clavicula in caput inserti pars a clavicula pronata, Ves. Pars eadem, septimi caput moventis, Col. Eadem septimi paris, eorum qui caput mo- vent, Eust. Eadem mastoidei, RioL Spig. Cowp. Mastoidei, Doug. Eadem ejus qui le sterno-mastoi'dien, ou mastoidien anterieur, Win. Coccygeus An quintus levator ani, RioL ? Coccygaeus, Doug. Musculus coccygis, Drake, Cowp. Levator coccygis, Morg. Triangu)aris coccygis, Sant. Le sacro-coccygien, ou coccygien posterieur, Win. PRIOR TO ALEINUS. 85 Complexus Secundi paris caput moventium, quartus mus- culus, moles carnea, Ves. Pars secundi musculi capitis, Col. Secundi moventis caput, FaL Pars complex!, RioL Cowp. Doug. Carnea quasdam moles quae trigemino adjun- gitur, Spig. Pars ejus qui le complexus, Win. Compressor naris Est de quo Fallopius, alium praeterea invenio musculum carneum, &c. An parvus nasi musculus, Cas. : qui est alius externus, qui alam naris dilatat sine ele- vatione nasi, RioL : et primi paris constrin- gentium alas, Spig. ? Elevator alae nasi, Cowf. De quo, Morg . Itaque animadvertimus in Eustachii tabulae, &c. Transversus, Sant. Videtur esse le transversal, ou inferieur, Win. Compressor prostatae Prostatae levatoris, seu adductoris, pars unius lateris, Sant. Le prostatique superieur, Win. Constrictor cunni i An est orbicularis musculi, suis fibris carneis, sinum (muliebrem) undequaque obvolven- tis, Arant. pars unius lateris ? Est clitoridis inferior latus et planus, RioL 86 SYNONYMS Portio carnosa in externa parte ipsius vaginae, De Mar. Alius musculorum paris, quod clitoridi a pie- risque adscribitur, De Graqf. Vagmaa masculi constrictorii, Verheyen, pars unius lateris. Eadem sphincteris vaginae, Cowp. The second muscle belonging to the clitoris, Doug. Sphincteris vaginae, Sant. pars unius lateris, L'autre muscle du clitoris l Win. Constrictor pharyngis inferior Pars ejus quae oritur a thyreoidea est commu- nium laryngis musculorum quintus et sex- tus, Ve$. Oesophagum complectentis, Col. pars unius lateris Tertii paris musculorum, qui faucibus dila- tandis aut constringendis interviunt, Fa!. pars inserta in primam cartilaginem laryn- gis. Ipse totus est communium laryngis muscu- lorum tertii paris, Fabric. Pars quae a thyreoidea, cesophagum ambien- tis, Cas. pars unius lateris Eadem quarti faucium, quem cesophageum vocant, Laur. Jiladem cesophagei, Riol. imi parjs cpastringentiura fauces, oesopha- PRIOR TO ALB1WJS. 8? giaei, Spig. et secundi par is, cephalo-pha- ryngei, pars in thyroidem cartilaginem in* serta Ipse totus, sphincteris, seu cesophagei, De Mar. pars unius lateris Pars quae a thyreoidea, cesophagei, seu sphinc- teris gulas, Cowp. pars unius lateris Paris thyro-pharyngei, Valsalv. Pharyngei pars quae thyreo-pharyngeus, Vals. Thyro-pharyngeus, Morg. Pars oesophagei, seu sphincteris gulae, Cowp. Thyro-pharyngeus, Sant. Le thyro-pharyngien, Win. Pars quae a cricoidea, est erico-pharyngeus, Valstdv. Pharyngei p^rs, quae crico-pharyngeus, Vals, Doug, Pars oesophagei, seu sphincteris gulae, Cowp, Crico-pharyngeus, Sant. Le crico-pharyngien, Win. Constrictor pharyngis medius Hujus pars, quas a cornu hyoidis oritur, est tertii paris musculortuii, qui faucibus dila- tandis aut constringendis inserviunt, FaL pars inserta in hyoidis latera Pars tertii faucium, Laur. Pars cephalo-pharyngei, RioL Secundi paris faucium, cephalo-pharyngei^ pars in hyoidis latera inserta, Spig* 88 SYNONYMS Pterigo-pharyngei, Cowp.^ pars quae oritur from the extremities of the os hyoides Ipse totus est paris hyo-pharyngei, Valsalv. Pars quas a cbrnu, pharyngasi, Doug* pars quse hyo-cerato-pharyngxus Pars quas ab ossiculo graniformi, pharyngaei, Doug . pars quas chondro-pharyngaeus Ipse totus, pterigo-pharyngei, Drake, pars qux from the os hyoides fiyo-pharyngeus, Morg. Sant. Pars oesophagasi, seu sphincteris guls, Cowp. Le hyo-pharyngien, Win. Pars inserta ossi occipitis est pharyngai, Doug . pars quse cephalo-pharyngeus Pharyngis musculi solitarii, seu azygi, Sant. Le cephalo-pharyngien, Win. Constrictor pharyngis superior Pars ejus quae oritur a maxilla inferior. An est septimus et octavus linguae musculo- rum, Ves.? Nonus ac decimus linguas musculus, Col. ? Primi paris propriorum linguae, Arant. ? Milo-glossus, Riol. 1618 et 1626? quern prasteriit ann. 1649? Quart! paris linguae, attollentis, mylo-glossi, Spig. * Paris mylo-glossi, Vesting. ? De Mar. ? Paris mola-lingualis, Verheyen ? Est pharyngaei, Doug, pars quas mylo-pharyn- geus. PRIOR TO ALBINUS. )$ An mylo-glossus, Morg? Oesophag^i, seu sphincteris guise, Cowp. pars,, qua? oritur ab inferiore maxilla. Paris mylo-pharyngsei, Sant. Haud dubie le mylo-glosse, Win. Pars quae a lingua, tertii paris musculorum, qui faucibus dilatandis a,ut constringendis inserviunt, FaL pars quae inseritur in radi- cem linguae Pterigo-pharyngei, Cowp. pars quae oritur from the root of the tongue. Paris glosso-pharyngei, Vdlsalv. aut pars ejus. Pharyngei,Do^. pars quae glosso-pharyngeus. Pterigo-pharyngei, Drake , pars quae from the side of the tongue Oesophagei, Cowp. quae oritur a radice lin- guae. Paris glosso-pharyngei, Sant. Le glosso-pharyngien, Win. Pars quae a processu pterigoideo, fortasse est spheno-pharyngeus, Vesting. Et paris spheno-pharyngaei, sive pterigo-pha^ ryngei, De Mar. Est pterigo-pharyngei, Cowp. pars quae oritur from the pterigoidal processes of the os cuneiforme Pharyngaei, Doug, pars quae pterigo-pharyn- geus. Pterigo-pharyngei, Drake, pars quae from the processus ptcrigoides. 00 SYNONYMS Est par is pterigo-pharyngei, Morg. Sant. Oesophagei, Cowp. pars quae oritur a processu pterigoideo. Le pterigo-pharyngien, Win. Pars quae a tendine circumflexi oesophagaei, Cowp* pars quas a tendine pterigo-staphy- lini. Pars quse a genio-glosso, baud dubie lacer- tus alter ab lingua ad pharyngem, Sant. Est le gemo-pharyngien, Win. Portio a petroso, an pharyngaei, Doug, pars qua? salpingo-pharyngeus? Le petro-pharyngien, Win. Corac o-b r ach i alis Carnosa pars interioris principii cubitum flee- tentium primi, Fes. Carnosa pars alterius initii primi cubitum flectentis, CoL Primi cubitum flectentis insignis musculosa portio, quam inter humeri motores jamdiu recenseo, Arant. Coracoideus, sive coraco-brachieus, RioL Portio carnosa, quam Piacentinus pro peculi- ari musculo habuit, perforatum app^llans, Cos. Coraco-brachialis, Cowp* Coraco-brachial, Win. Coraco-hyoideus ajjj Est septimus et octavus propriorum ossis referenti, Ves* S PRIOR TO 4XBINUS. Ql Quartus hyoidis, Col. Quarti paris hyoidis, Fal. Quarti paris, ossi hyoidi, ad linguae motum destinatorum, Arant. Quarti paris ossjs hyoidis, Cas. Coraco-hyoideus, Riol. Cowp. Doug. Paris quarti, oblique deorsum trahentis, cora- co-hyoidei appellati, Spig. Coraco-hyoides, Mvrg. Coraco, seu costo-hyoides, Sant. L'omoplat-hyoidien, cojnmunement coraco- hyoidien, Win. Corrugator supercilii pst qui sub cute supercilii, Goiter. An pertinet ad supercilii musculum, Fab. ? Notatus a Volchero Goiter, deprimendo, cor- rugando, et retrahendo versus nates super- cilio destinatus, RioL Corrugator, Cowp. Morg, + Musculus frontalis venjs, seu corrugator Coiteri, Doug. Corrugator supercilii, Santf* Le muscle sourcillier, Win, Cremaster Virilis testis musculus, Ves* Musculus testiculi, Col. Testis musculus, Fed. Musculus testis, Lour. Cremaster, KioL T. Earth. Spig. De Mar, DC Graqf. Cowp. Doug. Sant. J^e Cremaster, Win, 92 SYNONYMS Crico-arytaenoideus lateralis Propriorum laryngis septimus et octavus, Ves. Alter musculus, nunc dicto contiguus, &-c. Musculorum laryngis, qui ipsius proprii dicuntuf, tertius, Col. Ex propriis laryngis musculis, internorum, primi pans, Fabric. Unum par ab innomi- nata, &-c. Quibus musculis opponuntur illi qui utrmque in angulo sunt, &c. Tertii paris laryngis propriorum, Cas. Alterum vero eidem ossi, alarum instar, pras- positum, &c. Extendcntis ad latera, sivc aperientis rimularn secundi paris. Grico- arytenoidei lateralis., Spig . Crico-arytaenoides lateralis, Cowp* Crico-arytaenoideus lateralis, Doqg-, Le crico-arytenoidien lateral, Win. Tlrico-arytaenoideus posticus Propriorum laryngis quintus et sextus, Ves. Musculorum laryngis, qui ipsius proprii di- cuntur secundus, C&l. Ex propriis laryngis musculis posterior, ab infima innominatae parte, &c. Fabric. Huic oppositus est, qui extendit, &-c. Secundi paris laryngis propriorum, Gas. Paris Cu- cullaris. Crico-arytenoideus, RioL Extendentis recta, sive aperientis rimulam paris priroi, crico-arytaenoidei postici, Spig. PRIOR TO ALSINUS. 93 Crico-arytasnoidius posticus, Cvwp. Paris crico-arytaenoidsei posterioris, Morg. Crico-arytxnoidaeus posticus, Doug. Le crico-arytenoi'dien posterieur, Win. Crico-thyreoideus De hoc, Fesalius, Quatuor itaque primam se- cundas jungentium, &c. Musculorum laryngis, qui ipsius proprii dicun- tur, primus, Col. Paris quod exortum a cricoide cartilagine in scutiformem inseritur, FaL Ex propriis laryngis musculis anterior exte- riorque, Fabric. Prxter hos notantur in scutiformi, &c. Primi pans propriorum laryngis, Cas. Crico-thyroideus anticus, RioL Alterius paris extendentium, crico-thyroidei antici dicti, Spig . Paris crico-thyroidis, Veding. Verheyen. Paris crico-thyroidei, De Mar. Crico-thyroideus, Coivp. Doug* Crico-thyroides, Sant. Le crico-thyroidien, Win. Cruralis Pars octavi tibiam moventium, Fes. Pars octavi tibiae musculi, Col. Crureus, Sylv. Riol. Doug. Extendentium tibiam quarti, vasti interni, Spig. Femoreus, De Mar. 94' SYNONYMS Crureus, seu femoreus, Cowf* Le crural, Win. Cucuilaris Secundus scapulam moventium, Cucuilaris, CoL Spig. Trapesius, RioL Cucuilaris, et trapezius, Cowp* Le trapeze, Win. Curvator coccygis D Deltoides Secundus brachium moventium, Fes. Secundus humeri musculus, eporais, deltois, et humeralis, CoL Secundus movens humerum, YaL Deltoides, RioL Steno. Lower. Cowp. Elevator, attollens humerum, p. Act. Erud. ann. 1699, Septemb. Intertransversales, Doug. Sunt partes priores intertransversalium, Cowp, Aut horum aliqui, aut posteriorum, aut par- tes utrorumque, sunt les petits transver- saires du col, Win* Latissimus colli Est alterius lateris primus musculiis, eorum qui buccas et labra movent, Ves. Musculus latus in collo positus, Col. JTAaruo^a yuy&iSef, FdL Quinti paris maxillae, Ar&nt< Musculus auriculas et Htrique labro commu- nis, Cos. Musculus latus, RioL Detrahens quadratus, comrnunis buccarum labiorumque, Spig< Quadratus genae, seu tetragonus, Cawp. 1694. Quadratus genas, vel latissimus colli, Doug. Quadratus genag, or quadratus colli, by some called tetragonus, and by Galen platys- ma myoidei, Co*Wp< 1724. Platisma-myodes, Sant. Le peaucier, Win. Pars ex mala nascens, est tisoxius Sant, J14 SYNONYMS Pars ad auriculam pertinens, est portio mtis- culi cutanei supra parotidem ad aurem ad-t scendentis, RioL Adducens ad anteriora, Spig . Sunt fibrae carneae a musculo quadrate colli ad partem auriculae inferiorem delaue, Vcd* salv. , The common, proceeding from the quadra- tus gense, Doug. JLatissimus dorsi Quartus brachium moventimu, Ves* Quartus humeri musculus, Col. Quartus musculus movens humerum, Fal. Latissimus, aniscalptor, aut dorsalis maximus,, Lour. Anisealptor, anitersor, latissimus, Rid. Spig* Latissimus dorsi, sive aniscalptor, Cowp. Latissimus dorsi, Doug , Morg , Le grand dorsal, Win. Laxator tympani Alter in superiori meatus auditorii regione eonsistens, Cos, Qui a me primum inven- tus est, ait Gas, Novus muscuhis, Fabric* Exterior, Efvsd. Aurb internas externus, RioL Spig. Externus mallei, Schelhamerus cie Auditu. Externus auris, vel laxator externus, Musculus processus minoris mallei, TO ALBINtfS. Externus auris Aquapendent. vel Jul. Casser, Placent. Doug. Le muscle externe ou superieur du rrtarteau^ Win. jLevator anguli oris An est pars alse nasi musculi, pnesentis capitis (de buccarum, labrorum, et nasi alarum musculis) in altero latere quinti, aut omni- um noni et deciipi, Ves. ? Jpse tamen tertii eorundem par if, qui sunt. zigQmatici majores, partem esse suspica- tus est, in Examine Obs. Fallop. in nasi alas, labia, et buccas moventibus \ Num ter- tium vero meum, &c. Est de quo FaL Dum tertium par descripsit, novum musculum praetermisit, &c. De quo RioL labrum inferius surstim trahituif a musculo, &e. Secundus ad latera trahens, sive Elevator labiorum, Cowp. Elevator labiorum communis, Doug. Elevator labrorum communis^ seu caninus^ Sant. Le canjri, Win* Levator ani Musculus sedem attpllens, Latus, CoL Laur. Spig. leyatpr am, RioL 115 SYNONYM* Levator ani, Cowp. Morg. Sant. Heist. Levator magnus seu interims, Doug . An etiam partes ejus in faemina sunt musculi vaginae* Doug. App. concerning the JVuiscles o. the Clitoris ? Le releveur de Panus, Win. Pars tenuis, quae ad eum accedit, est alter ac postremus sphincteris lacertus, Sant. jLevatores breviores costarum An sunt intercostalium externorum initium primum a transversis vertebrarurn processi- bus, Spig.? Sunt levatores costarum, Stem. Morg. Costarum levatores Stenonis, Doug . quo etiam pertinet the fourth scalenus. Supracostales breves, Verheyen. Intercostalium externorum partes, Cowp. Les sur-costaux, Win. Levatores longiores eostarum Supracostales longi, Verheyen. Les sur-costaux, Win, Levator labii superioris Est pars afoe nasi musculi, praesentis -capitk (de buccarum, labrorum, et nasi alarum musculis) in altero latere quinti, aut omni- um noni et decimi, Ves. Pars pans sexti (eorum, quibus narium pinnae-, labia, et totius faciei cutis moventur) ab ipso (Vesalio) quinto in loco numerati, FaL Ex propriis, qui superius labrum sursum tra-. bit, Riol, 4 PRIOR -TO ALBINUS. ^ars primi nasi alas abducentis, Spig. Elevator labii superioris, Cowp. Pars elevatoris labii superioris proprii, Doug. Elevator musculus proprius labri superioris, seu incisorius, Sant. L'autre portion de 1'incisif lateral, Win. Levator labii superioris alaeque nasi Est pars alae nasi musculi, praesentis capitis (de buccarum, labrorum, et nasi alarum musculis) in altero later e quinti, aut omni- um noni et decimi, Fes;. Pars paris sexti (eorum, quibus narium pin- nae, labia, et totius faciei cutis moventur) ab ipso (Vesalio) quinto in loco numerati, FaL Vide et Columb. Musculus supercilii musculo junctus, superior! labro insertus, Cos. Pars primi nasi alas abducentis, Spig. Retractor alae nasi et elevator labii superioris, Cawp. 1694. The second of the common of the nose, Doug. Pars elevatoris labii superioris proprii, Efusd. Dilatator alae nasi et elevator labii superioris, Cowp. 1724, Pyramidalis, cum pyramidalis vel socio vel parte, Sant. La grande portion de 1'incisif lateral, una cum illo, quern dicit, le muscle oblique ou lateral, Ejusd. ut videtur. Levator menti Est elevator labii inferioris, Cowp. SYNONYMS Elevator labii inferioris proprius, Elevator labri inferioris, Sant. L'incisif inferieur, Win. fLevator palati mollis Est baud dubie secundi psris musculorum^. qui faucibuS dilatandis, aut constringendis inserviunt, Fed. i^uem ex Fallopio sphenopharyngei nomine descripsit, RioL Est pterystapliilinus internus, RioL Secundi paris dilatantis fauces, Spig. Paris interni gargareonis, Vesting. Paris pterygo-staphylini interni, Le Mat'. Spbaeno-palatinus, Cowp. 1694. Morg. Paris salpingo-stapbylini, Valsalv. Columelfe musculus, in triangularera ex- pansionem deorsum productus, Morg. Salpingo-stapbilinus,Valsalv. Pteri-staphilinu? externus vulgo, Doug. Sphaenostapbilinus, Drake, Cowp. 1724. Salpingo-stapbylinus, seu salpingo-palatinus, Sant. Paris spbeno-staphylini, rectius salpingo-sta r phylini, Heist. Le petro-salpingo-stapbylin, ou salpingo-sta 7 pbylin interne, Win. Levator palpebrx superioris Est palpebrarum secundus, oculum aperien^, Col TO ALBJNUS. Musculus parvuset tcnuis, &c palpebram attollens, Fat. De quo Ves. Is namque gracili admodum principio, &c. Exam. Obs. Fal. in Palpebram moventibus. Qui superior! palpebne aperiendac dcstinatus est, Arant. Rectus, Fabric. Palpebrx supcrioris primus, Cos. Superiorem palpebram attollens, Riol. Apertor oculi, attollens palpebram superiorem, Pyramidalis, Molin. Aperiens palpebram rectus, Cowp* Doug* Le relevcur propre, Win. Levator scapulae Tertius hominis scapulam moventiura, Tertius scapulae musculus, CoL Levatores proprii, Lam; Levator, Riol. Scapulum attollens, levator, patientise muscu lus, Spig. Levator scapulas, Cowp. Morg. Elevator, seu musculus patientise, Doug. Le releveur propre de Pomoplate, Win. L'angubire, dit communement releveur pro- pre, Ejusd. Liflgualis Lingualis, Doug. An les fibres longitudinalcs, Win. ? SYNONYMS , jLongissimus dorsi Undecimus et duodecimus dorsum moven- tium, Fes. Secundus musculus dorsi, CoL Quinti paris dorsi musculorum, prxter par- tern spinis vertebrarum thoracis insertam, FaL Semispinatus, RioL Dorsi longissimus, Spig. Dorsi longissimus, praeter partem quse inserta spinis thoracis, Cowp. Longissimus, Doug . . Longissimus dorsi, Morg, Le long dorsal, Win. Longus colli Est alterius musculorum, quos fere sub sto- macho latitantes veteres appellasse viden^ tur, pars cervicis vertebrarum corporibus inserta, Ves. Pars eadem primi et secundi dorsum moven- tium, Ejusd. Primi cervicis musculi, CoL pars vertebrarum . corporibus annexa. Pars alterius lateris musculi stomacho subjec- torum, Eust. Longus, RioL Cervicem flectentium primi paris, sive longi, Long.us .colli, Cowp. Morg. PRIOR TO ALAINirS, Longus, Doug. Le long du col, Win. jLumbricales manus Musculi quatuor digitos pollici adducentes, Ves. ftuatuor extremae manus musculi, post pri- mum, Col. Quatuor, qui parvi admodum in vola harent chordis secundi, Fed. Lumbricales, RioL Cowp. Doug. Flectentes primum internodium, Spig. Les muscles lombricaux, Hunauld. Les muscles lumbricaux, Win. Lumbricales pedis Sunt 19, 20, 21, 22, pedis digitos moventium, Ves. . Quatuor musculi pedis digitis inservientes, CoL Extremi quatuor musculi, quos inter motores digitorum pedis descripsit Vesalius, Fd. Lumbricales, RioL Cowp. Doug. Morg. Flexores quatuor primi internodii, lumbrica* les, Spig. Les lumbricaux des orteils, Win, M Major helicis Helicis musculus, Sant, Masseter Est inferiorem maxillam morentium alteriu lateris secundus, seu masseter, Fes. Masscterus et mansorius dictus, Col. Massiter, Fal. Tertius attollens maxillam masseter, RioL Tertii paris lateralis, Spig. Masseter, Cotvp. Doug. S&nt. Le masseter, Win. Minor helicis Fibrae muscullres in plana helicis facie, Sant* Multifidus spinae Pars cjus, quae in lumbis, est decimus tertius, ct decimus quartus dorsum moventium, Ves* Tertius dorsi musculus, CoL Quae in dorso, est decimus quintus, et deci- mus sextus dorsum moventium, Vet* Quartus dorsi musculus, CoL Quse in collo, est pars septimi et octavi dor* sum moventium, Ves. Quarti cervicis musculi, CoL Pars tertii paris dorsi musculonrm, Fal. Quae in lumbis et dorso, est quarti paris dorsi musculorurn, FaL An sacer, Rid. ? Qv.2C in collo, pars spinati, RioL Spfe* Transversalis colli, Cowp? Transversalis, Dong. Sunt les vertebraux internes du demi-epineux, ou transversaire epineux du col, Win. PRIOR TO A1BIKT1S- in dorso, semispinati, *S^z. pars, ut vide* tur. Semispinatus, Cowp. Transversales dorsi interioies, Doug. Le demi-epineux, ou transversaire epinemc du dos, aut fortasse ejus tantum partes in- ternee, Win. ftuae in lumbis, paris sacri, Spig. Sacer, Cowp. Transversalis lumborum, vulgo sacer, Doug. t,e transversaire epineux des lombes, ancien* nement le sacre, Win. Portiones distinctae in cervice, sunt liaud dubie intervertebrales, Doug. ^lylohyoideus Secundi paris ossi v referent! prbpri6rum f VOs. Secundi paris hyoidis ossis, Fal. 5ecundi paris ossi hyoidi, ad linguse motum destinatorum, Arant. Primi paris ossis hyoidis, Cos, Milohyoideus, Riol. yrimi paris, recta attollentis, geniohyoidei, Mylohyoideus, Fal. Doug. Morg, Cowp, Mylo-hyoides, Sant. J^e n)yjo-hyoidien, Win* 124 SYNONYMS N Nasalis labii superioris An ad elevatorem labii superioris proprium,, relatus a Cowpero? Est tertius fibrarum ordo, &c. Sant. Caeteri non distinxerunt ab orbiculari oris. O Obliquus externus abdominis Oblique descendens, Fes. Fabric. De Mar. Verlieyen. Morg. Obliquus descendens, Col. Riol. Spig. Cowfi* Doug. Obliquus externus, Laur. Obliquus descendens, seu exterior, Sant. L' oblique externe, Win. Obliquus inferior capitis Sexti paris caput moventium, Ves. Quintus caput movens, Col. Septimus capitis, FaL Parvus musculus a secundae vertebrae spina in processum transversum primse oblique in- fixus, Eust. de Motu Cap. Obliquus major, Riol. Paris obliqui inferioris, Spig . Obliquus inferior, Cowp. Doug. Ju'oblique inferieur, ou grand oblique, Win. tfRIOR TO ALBINUS. Obliquus inferior oculi Vide Ves. Lib. II. cap. 11. Circumductionis O*. pifices. Est quintus oculi, Col. Sextus, FaL Obs. an. in Musculis Oculorum f et Ves. Exam, in Oculos Moventibus. Obliquus alter brevis, Arant. Obliquus infernus, Fabric. Sextus, Cas. Inferior, seu minor obliquus, RioL Quintus, qui obliquus primus est, et volvens, sive circumagens, exterior nobis dictus, aut inferior, Spig. Obliquus minor, Molin. Obliquus inferior, Gowp. Doug. Morg. L\j>blique inferieur, Win. Obliques internus abdominis Oblique adscendens, Ves. De Mar. Verheycn. Obliquus ascendens, Col. Fabric. De Respir.. RioL Spig. Cowp. Doug. Drake. Obliquus internus, Laur. RioL Anim. in Laur. Morg. Obliquus alter, seu interior, Sant* L'oblique interne, Win. Obliquus superior capitis Quinti par is caput moventium, Sextus caput movens, CoL Sextus capitis, Fah 126 StNONY&S Obliquus musculus, qui retro a transver;*f primae vertebras processu in caput inseri- tur, Lust. Obliquus minor, Rio!. Paris obliqui superior is, Spig. Obliquus superior, Cowp. Doug, L'oblique superieur, ou petit oblique, Win* Obliquus superior oculi Vide Ves. Circumductionis Opifices. Tertius palpebrarum, CoL jDuorum in gyrum flectentium prior, Fa!. Quintus, Ejusd. et Ves. Exam, in Oculos Mo- ventibus. Obliquus illequi per trochleam ducitur^rajtf, Trochlese musculus, Fabric. Trochlearis, Cos. Alter ex obliquis superior, seu major, RjoL Sextus, obliquorum secundus, .circumagens interior, aut superior, vel etiam major, Spig. Obliquorum, qui major est, Molin. Obliquus superior, or trochlearis, Gowp. Obliquus superior, Loug. Morg. L'oblique superieur, Win. An gracillimus est rectus quintus, Mtfin* el musculus trochlearis, Ejusg* Obturator externus Nonus femur moventiu-m, Pes* Nonus femoris musculus, CoL Duodecimus, Arant. Externus obturator, Ktil* PRIOR TO A1BINUS, Circumagentium secundus, externus pbtura* tor, Cowp. Doug. L'obturateur externe, Win. Obturator intern-as Decimus femur moventium, fas* Decimus femoris musculus, CoL Obturator internus, RioL Morg. Circumagentium tertius, obturator internu^ Marsupialis, seu bursalis, Cowp. Marsupialis, sen obturator internus, Doug. I/obturateur interne, Win. Opponens pollicis manus Est illorum duorum, qui pollicis primo famulantur, primus, aut pars ejus r una cunj secundo, I^es. Decimus, una cum undecimo, JFW An et hie pars thenaxis, KloL Est primi internodii pollicis flexor secundus f cum primo, aut parte ejus, ut videtur, Spi s . Pars flexoris primi et secundi ossis poUicis, Cowp. Flexor primi internodii pollieis, Doug. Pars ejus qui le thenar, Win* Orbicularis oris Est moles carnea, niusculosa tamen quas u- trumque labium fonnat, Fal. Vide quae Ves. in Exam. Observ. FaL in Nasi Alas, Labia, et Buccas moventibus, in 12& SYNONYMS Musculus orbicularis, Rial. Quartum par, constringens, Spig. Constrictor labiorum, Cowf. 1694. Sphincter labiorum, Doug . Orbicularis labiorum, Cowp. 1724. Vide Sant, Obs. Quo etiam pertinet corrugatoris, seu protrusoris, Ejusd. interior ordo. Les demi-orbiculaires, Win. Portiones accessorise inferiores sunt product- res inferioris labri, Sant. Les accessoires du demi-orbiculaire inferieur, Win. Portiones accessorise superiores sunt labri sn- perioris fibrarum secundus ordo, Sant. Les sur-demi-orbiculaires, Win. Orbicularis palpebrarum Duo palpebrarum musculi, Ves. Palpebrarum primus, orbicularis, Col. Exterior, qui totum oculum ambit, Fd. Orbicularis palpebrarum, Fabric, una cum su percilii musculo, Ejusd. Orbicularis palpebrse musculus major, Cas. una cum minoribus palpebrarum muculis, Ejusd. Orbicularis latus cum ciliari, Riol. Qui claudentes palpebras, sive semicircula^ res, Spig. Sphincter, Molin. Orbicularis palpebrarum, Cowp. Orbicularis oculi, Sant, TO ALBtNUS* / ! Lie muscle orbiculaire, Win. Portio quae se adjungit ad levatorem labii superioris, est perpetuus lacertulus ab imo orbiculari, Sant* Palatopharyhgeus Aut hie, a ut, constrictor isthmi faucium, silnt Ics fibres demi-circulaires, &c. Dionis, A- nat. VIII. Demonst. On voit a cote deux ar- cades qui font Tentree des fentes nasales; elles sorit faites de fibres demi-circulaires, Est pans pharyngostaphylini, Vahalv. et sta- phylinopharyngaei, Ejusd. Musculus columellae, in thyroidis lateralem oram infixus, Morg. Thyreo-staphilinus, Dong. Sunt fibrae carnese, quae oriuntur from the side of the uvula, Drake. Est oesophagei, Gowp. pars springing from the uvula. Thyro-palatinus cum hypero, seu palato-pha- ryngseo, Sant. Le pharyngo-staphylin, una cum eo qui le thyro-staphylin, Win. Le thyro-pharyngo-staphylin, quo etiam per- tinet le peristaphyli-jpharyngien, EJUS& I SYNONYMS Palrtiaris brevis Esfe im' altro musctilo, ehe distende questa tela^ Vatverd. Primus extreme manus musculus scriptoribus ignotus, Col. Caro quaedam, quee musculorum effigiem ha- bet, Fal. Carpieus, vel palmaris brevis, Riol. Caro quaedam quadrata, Spig. Palmaris brevis, Cewp* Palmaris brevis Joan^ Bapt. Carman, vcl ca- ro quadrata, Doug. Le palmaire cutane, Win* Palmaris longus Musculus, nervosa sua exilitate mediae volae,' et internse digitorum sedis cuti subnatus, Ves* Primus musculus manus interior, Col. - Latescentis chordae musculus, FaJ. Palmaris, Riol. Spig. De Mar. Morg. Palmaris longus, Coivp. Doug. Le cubital gresle, commun^ment nommc long palmaire, Win. Pectineus * Pars octavi femur moventium, Ves. Septimus femoris musculus, Col. aut ejus pars* Pectineus, Riol. Cowp. Fiectentium quartus, Spig. Pectinalis, Dougi Le pec tine, Win. Pectbralis Primus brachium morentiu iti, PJUOk TO ALBINtlS. 131 Primus hiimeri musculus, Co?* Pectoralis, Rial. Spig. VerJieyev. Cowp. Doug. Le grand pectoral, Win. Peroneus brevis Octavus pedem moventium, Ves. Quintus anterioris pedis musculus, Coh Peroneus anticus, Rioh Flectcntium pedem secundus, peronseus se cundus semifibulaeus, Spig. Peroneus secundus, Cowp. Peronaeus secundus, seu anticus, Doug. Le mbyen peronier, communement dit pe* ronier anterieur, Win. Peroneus longus Septimus pedem moventium, Ves. Quartus anterioris pcdis musculus, Col. Peroneus posticus, Rioh Oblique moventium pedem, secundus abdu- cens, peronseus primus, fibulaeus, Spig. Peronaeus primus, Cowp. Peroneus primus, seu posticus, Doug. Le long peronier, communement dit pero- nier posterieur, Win. Peroneus tertius Nonus pedem moventium, / Musculus pedis qui tertius decimus annume- ratur, Col. Pto exsensoris digitorum pedis longi, Cowp. Vesalius's ninth muscle of the foot, Doug, in Extensore longo 12 4uifttus tencto extensoris longi digitorum dis, Morg* Le petit peronier, Win* Jlantaris Tertifcs pedem moventium, Vcs< Tertius tibiae musculus, Cat. Plantaris, RioL Spig. Coivp. Morg. Extensor tarsi minor, vulgo plantaris, Doug* Le jambier gresle, dit vulgairement plantaire f Win. Popliteus Musculus in poplite occultatus, Fes* Decitnus tibiae musculus, CoL Popliteus, RloL Cowp* Doz/g-. Oblique movens tibiam, suppopliteus, Spig, Le poplite, ou jarretier, Win* Profundus Secundus digitos moVentitim, Ves. Quintus manus musculus interior, CoL Secun'dtis, Arant* Prcrfundus, RioL Flexor tertii digitorutn internodii, Spig* Perforans, Coivp. Doug* Le profond, Hunauld. Le perforant, Gommunement le profond, Win* Pronator quarfratus Primus radium peculiariter agentium, Ves.' Ottavus manus interior musculus, Inferior pronator quadratus, Rfol. -PRIOR TO ALBINVS. 133 t^onatorum primus* sive quadratus, Spig. Pronator radii quadratus, Cowp. l694 Pronator quadratus, Doug . Pronator radii quadratus, or inferior quadra- tus, Cowp. 1724. Le pronateur quarry, ou transverse, Win. f*ronator teres Tertius radium peculiaritcr agentium, Ves, Septimus manus interior musculus, Col. Superior pronator rotuodus, RioL Pronatorum secundus, siv.e teres, Spig. Pronator radii teres, Cowp. Pronator teres, Dovg. Le pronateur rond, ou Toblique, Win, Psoas magnus . Femur moventmm sextus, Ves. Quintus femoris, Col. Lumbaris, sive psoas, Riol. Lumbalis tnusculus, Spig. Earth. Psoas magnus, seu lumbalis, Cowp. Psoas magnus, Dovg. Morg. Le psoas, ou lombaire interne, Win. fsoas parvus Parvus psoas, RfaL DC Mar. Cowp. Doug., Morg. Le petit psoas, Win, 'Pterygoideus externus musculorum, 134 SYNONYMS Musculi temporalis ilia pars, quae ab e na sede processuum, quos vespertilionum alis comparamus, &c. Ves. Quintum par exerendae maxillae Fallopio ad- scriptum, Arant. Pterygoideus externus, Riol. Cowp. Quarti paris, pterygoidei abducentis, Spig, Paris pterygoidis, sive Claris extern!, Vesting* Pterigoidaeus externus Fal. Dong. Pterigoides exterior, Sant. Le. petit pterygoidien, ou pterygoidien ex- terne, Win. Pterygoideus internus Tertius musculus qui in ore latitat, Vts. Musculus in ore latitans, Col. \ Latens in ore, Fal. Pterygoideus internus, Riol. Coivp. Doug. Quinti paris maxillam abducentis, Spig. Paris pterygoidis, sive alaris intcrni, l^csling. Pterigoides interior, Sant. Le grand pterygoidien, ou pterygoidien in^ terne, Win. Pyramidalis An musculus parvus qui procedit a fine mus- culi longitudinalis, Massa ? Est superius principium recti abdominis, Ves. Carneum, CoL Musculus quidam totus carnosus, Fal. Carneum operculum, PRIOR YO AIBINUS. Pyramidalis, RioL Spig. De Mar. Cowp. Doug. Vcrheyen. Sant. Le pyramidal, Win. Pyriformis Quartus femur moventium, Fes. Quartus femofis musci|lus, Col. Frimus et superior quadrigeminus, iliac us exr ternus, Ri&I. C i re umagentium primus, iliacus externus, py- riformis, Spig. Pyriformis, seu iliacus externus, Cowp. Le pyriforme, ou pyramidal, Win* Quadratus femoris An est pars quinti femur Tnoventium, Pars octavi femoris musculi, Col. ? st undecimus movens femur, Fat. Undecimus, Arant. Quartus quadrigeminus quadratus, Rial. Circumagentium quartus, Spig. Quadratus femoris, Goivp. Dong. Le quarre, Win. Quadratus lumborum Nonus et decimus dorsum moventium, Fes* Primus dorsi musculus, Col. Sexti paris dorsi, Fah Quadratus, RioL Doug. Parjs lumborum quadrati, Spig. SYNONYMS Quadra tus lumber um, Le quarre des lombes, ou lombaire extcrue, Win. Radialis externus longior et bmvior Longior, una cum breiviore, quartus brachiale. moventium, Ves. Septimus manus ^xterior musculus, Col. Longior est radieus externus, qui a,b acumine osseo brachii enascitur, RioL ,Brevior est radieus externus, qui a condylo externo brachii oritur, Ejusd. Longior, una cum breviore, est extendentium (carpum) exterior, Spig. Longior est, the outermost muscle, Cowp. in Extensore Carpi radiali. Extensor carpi radialis longus or superior, Dong. Le radial externe premier, Win* Brevior est, the other beginning, &c. Cowp. Extensor carpi radialis brevis or inferior^ Doug. Le radial externe second, Win. Radialis internus / Secundus brachiale moventium, Ves. Tertius interior manus musculus, Col. Radieus internus, RioL ilectentium (carpum) exterior, Spig. PRIOR TO ALBINUS. flexor carpi radialis, Cowp. Doug. Le radial interne, Win. Recti oculi Attollcns est tertius oculum movens, Vcs. Unus ex quatuor oblongis musculis, Col. Unus ex quatuor qui rectis motibus praefecti, Fal. Ex iis qui rectis famulantur motibus, Arant* Rectus superior, Fabric. ftui a physiognomic is superbus dicitur, Cos. Attollens, sive superbus, Riol* Primus attollens, Spig. Superbus, Molin. Elevator oculi, Cowp. Elevator, Doug. Le releveur, Win. Abductor est secundus oculum movens, Ves. Unus ex quatuor oblongis musculis, CrJ. Unus ex quatuor qui rectis motibus pra^fecti, Fal. Ex iis qui rectis famulantur motibus, Arant* Rectus exterior, Fabric. Quem indignatorium appellant, Cos. Abducens, sive indignatorius, RhL Quartus abducens, Spig. Iracundus, Molin. Abductor oculi, Cwcp. Abductor, Doug. L'abducteur, Win. est quart us oculum movens, Ves. 138 SYNONYM* Unus ex quatuor oblongis. musculis, C$1. Unus ex quatuor qui rectis motibus prsefecti, Fa!. Ex iis qui rectis famulantur motibus, Aront. Rectus inferior, Fabric. Qui humilis vocatur, Cos. Deprimens, sive humilis, Rial. Secundus, sive depressor, Spig, Humilis, Molin. Depressor oquji, Cowp 1 Depressor, DQU$* Deprimens, Morg, Jj'abaisseur, Win. Adductor est primus oculum movens, Fes, Unus ex quatuor oblongis musculis, Col. Unus ex quatuor qui rectis motibus praefecti, Ex iis qui rectis fhmul^ntuf motibus, ^.ectus interior, Fabric. Qui barbaris bibitorius appellatur, Qas^ Adducpns, sive bibitQiras, Rig}. Tertius adducens, Spig. Bibjtoriug, Motifa Adductor oculi,, Cowp, Adductor, Doug. L'adducteur, Win. Rectus abdominis Rectus, praeter ejus principium superius, Vet* Col. Arant. PRIOR TQ AJ.BINUS Rectus, Fabric. Riol. Spig. De Mar* Cowp. Doug. Sant. Le droit, Win. 'Rectus cruris Nonus tibiam moventium, Vet. Nonus tibise musculus, Col. Rectus gracilis, Riol. Extendentium tibiam secundus, rectus, Rectus femoris, Cowp. Rectus, Doug. Le droll, ou grele anterieur, Win. Le droit antcrieur, ou gresle anterieur, Ejusd- Kectus capitis interims major Est alterius musculorum, quos fere sub sto- macho latitantes veteres appellasse viden- tur, pars in os occipitis inserta, Ves. Pars eadem primi, et secundi dorsum mcven- titim, Ejusd. Primi cervicis musculi pars occipitio annexa, Col Nonus musculus capitis, FaL Alterius lateris musculi stomacho sirbjecto rum, portio in occipitis os inserta, Eust. Qui cum mastoideo caput flectit, Riol. Rectus internus major, Cowp. Doug. Le droit anterieur long, Win. Le grand droit antcrieur, Ejusd. Jlectus capitis internus minor Musculus digitalis latitudinis, ab eminentc quadam linea occipitis ossis principivim su- jnens, Rectus internus minor, Cawp, Le rengorgeur oblique, Dupre. Rectus internus minor Cowp. Doug, Jlectus antic us minor, Morg. Le droit ^nterieur court, Win. Le petit droifc anterieur, Ejusd. us capitis lateralis Musculus admodum parvus, qui a processn trans verso prira^c vertebrae ortus, FaL Alter musculus praedictis brevior et angustior, Eust, Musculus obliquus, qui ante a transverse pri- mae vertebrae processu in caput inseritur, Rectus lateralis, Cowp. Le rengorgeur drok, Dupre. Rectus late?rajis, FaL Doug. Morg. Le premier traa?versaire anterieur, Rectus capitis posticu majo* Tertii paris caput raoventium, J^es. Tertius musculus caput rnovens, CoL Major rictus, Rial. Rectus major, Spig. Cotwp. Doug. Le grand droit, Win. Rectus capitis posticus minor Quarti paris caput moventium, Ves* Quartus musculus caput movens, CoL Rectus minor, RioL Spig. Cowp. Le petit droit^ Win* PRIOR TO ALBlNtS. Retrahentes auriculae Auris musculus a rftammillari processu profi* ciscens, Col. Sccundus auriculae, FaL Secundus propriqrtim auriculae, Cos* Proprius auris extemae, Rial. Le second de Poreille, Du Verney. Retrahens auriculam, Cowp. Posteriores auriculae, Valsalv. Le poster ieur Vieussen, Win. Postetiores auriculae, ct postici, Sant. Hue quoque peninent postici corrugatores, setJ occipitales mifiores, Ejwd. Rhomboideus major Est pars major qtiarti scapulam moventium, Qxiarti scapulae musculi, CoL Rhomboidis, Laur R:oL Sptg. CoWp. 1694. The inferior part of the rhomboides, JDoitg* Cou>p. 1724. La portion inferieure da rhomboide, Win, Rhomboideus minor Est pars quarti scapulam moventiurn, Vex. Quarti scapulae muscuK, Col. Rhomboidis, Laur. Octavus omoplatse, Cabrolius. Rhomboidis portio superior prorsus secret^ Riot. Pars rhomboadis, Spig* 142 StNOCTAE! Quidam musculus, nunquam alias a me vi'sus; Bidho. The uppermost part of the rhomboides, Doug' a Cowp. La portion superieure du rhomboide, Win. Sacrolumbalis Quartus in alt^ro latere holninis thoracem moventium, Ves. Quint us thoracis musculus, Col. (,)iiartus thoracis musculus, Fal. Sacrolumbus, Laur. RioL Spig* Steno. Verheyen. Morg. Alius prseterea in dorso musculus, qui cum spinalibus musculis pertinacissime commis-^ cetur, Fabric. Sacrolumbus, una cum inferiore parte cervi- calis descendentis, Diemer. ' Sacrolumbalis, Cowp. Doug. Le sacrolombaire, Win. Salpingopharyngeus Sunt carnese fibrs, qua? oriuntur from the roots of the cartilage excavated for the me- atus a palato ad aurem, Drakt. Est salpingo-pharyngeus, Sant. An le spheno-salpingo-pharyngien, Win, ? Slartorius Primus tibiam movcntium, Vcs. Primus tibiae musculus, Col, T6 ALBINUS. 143 Longus, sive sutorius, RioL Flectentiumtibiam primus, sartorius, fascialis, fascia, Spig. Sartorius, Cowp. Doug, Le couturier, Win* Scalenus lateralis Ubi cdnjunctus cum medio, est octavi thora- eis musculi pars, quse inseritur in secun^ dam thoraeis, Fed. Videtttr esse scalenus secundus^ Cowp, aut pars ejus. An scaleni pars, a secunda costa enata, JMorgJ La portion anterieure du second scalene, Win. Scalenus medius Est pars tertii et quarti dorsum moventium, Pars secundi cervicis musculi, CoL Octavus thoraeis musculus, Fa!. Pars scaleni, RioL Pars paris triangularis, Spig. Scalenus tertius, Cowp. 1694, ut videtur. The second scalenus, Doug. An pars ejus est scalenus tertius, Cowp. 1724. Est la portion ou branche posterieure du mier scalene, Win. Scalenus minimus Scalenus posticus Nonus thoraeis musculus, Fal. The third scalenus, Doug, 144 Anscaleni pars, a costa secunda enata, M La portion posterieure du second scalene, Win* Sailenus prior Est pars tertii et quart! dorsiim moventiuirij Pfcf; Pars secundi cervicis rhuseuli, Col. Septimus thoracis, Fa/. Pars scale hi, Riot. tars paris triangularis, Spig. Scalenus primus, Cowp. The first scalenus, Doug\ La branche ou portion anterieure d\l premier scalene, Wim Semimembranosus Quintus tibiam rnovehtium, Vcs. Quartus tibiae musculus, Coh Semimembranosus, Riol. Steno. Cowp. Doug. Flectentium tibiam quartus, semimembraneus, Le demi-membraneux, Wim jSemispinalis dorsi Scrnispinalis, Doug. An sunt les vertebraux externes du derni-epi- neux, ou transversaire epineux du dos, Win.? Reliqui non distinxerunt vel a multifido, vel a spinali colli, aut accensuerunt partem u- triquCi Semitendinosus Tertius tibiam moventium, Ve:> Tcrtius tibise musculus, CoL TO ALBINUS. 145 Seminervosus, Riol. Sterio. Doug. Flecteritium tibiam tertius, seminervosus, Spig* Seminervosus, seu semitendinosus, Cowp. Le demi-nerveux, Win. Serratus anticus Musculus qui scapulam antrofsum agit, l^es. Primus scapulam rrioventiunij E/usd. Secundus scapulae, Col. SerratAs minor, Riol. Spig. Serratus anticus minor, Vesting. Cowp* Doug* Verheyen. Le petit pectoral, Win. Serratus magnus Secundus in altero latere thorace l m moven- tium, Ves. Secundus thoracis musculus^ Col. Qui a Galeno passirn rriiisctilus in simis scapu- larum situs appellatur, Fabric. Serratus major, Riol. Spig. Serratus major anticus^ Ferheyen. Coivp. Doug* Morg* Le grand dentele, Win* Serratus posticus inferior Quintus in altero latere thoracem hominis riio- ventium, fas. Quartus thoracis musculus, CoL Musculus ad infimarii dorsi partem, una cum alio musculo exiguo prsedicto super^ posito, Fabric. 149 Serratus posticus inferior, RioJ. Spig. forheyen. Cowp. Doug. Morg. Le dentele posteneur inferieur, Win. Serratus posticus superior Tertius in altero latere thoracem 'hominis mo* ventium, Fes. Tertius thoracis musculus, Col. Musculus ad supremarn dorsi partem prope cervicem, Fabric. Serratus postieus superior, Rlol. Spig. ffysling. Cowp. Doug. Verheyen. Morg. Le dentele posterieur superieur, Win. Soleus Qua.rtus pedem moventium, Fes* Quartus tibiae musculus, Col. Soleus, RioL Extendentium pedem seeundus, gasterocnc- mius internus, Spig. Gasteronocnemius internus, Cowp. The two innermost heads extensoris tarsi su- ralis, vel extensoris magni, Doug, Le soleaire, Win, Sphincter externus ani Musculus orbiculatim Jntestino obductus, Fes. Musculus orbicularis recti intestoi, sphincter dictus,. W. . priiri^s el e&ternus, e^rosu5, KioL Sphincter ani, Cowp. Sphincter exte^jius, Doug. TO ALBiNtiS. 147 Les sphincters cutanes, Win. - Pars per perineum procurrens, videtur esse levator ani sextus gracilis et acuminatus, Rioh Est Pun des muscules dilatateurs de Purethre, Lin-re* Ureihrae dilatator posticus, Heist. 1719* Penis musculus triangularis, Morg. Urethrae virilis, dilatator posticus, sive triangu* laris, Heist. 1727- Sphincter internus ani An est musculus cutaneus et circularis in extrema sedis ora collocatus, FaL ? Sphincter cutaneus, Laur. Sphincter cutaneus, ac superficialis, RioL Sphincter internus, Doug. Le sphincter intestinal, ou orbiculaire, Win* Spinalis cervicis Est pars septimi et octavi dorsum moventiurri, Quarti cervicis musculi, CoL Tertii paris dorsi musculorum, Fal. Spinati, RioL. Spig. Spinalis colli, Cowp. Spinalis, Dong. Les vertebraux externes du demi-epineux, otl transversaire epineux du col, Win. Spinalis dorsi Quinti paris dorsi musculorum, pars implan- tata in spinas vertebrarum thoracis, JW. Semispinati, Spig. pars, ut videtur. 148 SYNONYMS Dorsi longissimi pars, quse inserta spinis tho* racis, Cowp. Le grand epineux du dos, Win. Splenius capitis Primi paris musculorum aut caput, aut pri- mam vertebram moventium, Ves. pars qua in occipitium finit. Primi moventis caput, in occipitium implan- tata, Fat. Pars ejus, qui a recentioribus anatomicis ante alios descriptus, Eust. Splenii, Riol. Triangularis, splenii, Spig. Superior splenii, Cowp. Splenii, inserta processui mammillari, Doug. La portion superieure du splenius, ou masto- i'dien posterieur, Win. Splenius colli Primi paris musculorum aut caput, aut pri- mam vertebram moventium, Ves. pars quae in transveros vertebrarum processus nexum molitur. Pars primi caput moventis, Cot. Primi moventis caput, in processus transver- sos inserta, FaL Pars ejus, qui a recentioribus anatomicis ante alios descriptus, Eust. Splenii, Riol. Triangularis, splenii, Spig. Inferior splenii, Cowp. FRIOR. TO ALBINUS. Splenii, inserta vertebris colli, Doifg. Morg. La portion infeneure du splenius, ou masto- i'dien posterieur, Win. Stapedius Anne est ligamentum peculiare, a quo stape* sustinetur, Schclham ? Est le muscle de 1'etrier, Du Ver. Win. Musculus stapidis, Cowp. Stapedis musculus, Valsalv. Stapidaeus, vel musculus stapedis, Du Ver. Doug. Le second muscle de Poreille interne, que nous appellons petit, Vieus. Sternohyoideus Est ossi v referent! propriorum alterius lateris primus, Ves. Primus hyoidis, Col. Prirni parw hyoidis ossis, FaL Primi paris ossi hyoidi, ad linguae motum des- tinatorum, Arant. Secundi paris ossis hyoidis, Cos. Sternohyoidaeus, RioL Cowp. Doug. Secundi paris, detrahentis, sternohyoidei, Spig. Sternohyoides, Morg. Sant. Heist. Le sterno-hyoi'dien, ou sterno-cleido-hyo- Ydien, Win. Sternomasioideus Musculi a pectoris osse et clavicula in caput inserti, pars ex pectoris osse pronata, 150 SYNONYMS Pars eaclem septimi capnt moventis, CoL Eadem septimi paris, eortirn qui caput mo- vent, Eust. Eadem mastoidei, seu mastoideei Riol. Spig. Cowp. Doug. Eadem ejus, qui le sterno-mastoidien, ou mastoYdien exterieur, Win. Sternothyreo'ideus Communiuin laryngis musculorum tertius et quartus, Ve$. Primus communis laryngis, CoL Secundi paris communium laryngis muscu- lorum, Fabric. frimi paris communium laryngis, Cas. Bronchius, Riol. Primi paris extendentiuin thyroidem, vulgo. bronchii dicti, at nobis sternothyroidei, Spig. Sternothyfoideus, Cowp. Doug. Sternothyroides, Morg. Sant. Le sterno-thyroidien, Win. Stylo-glossus Quintus ct sextvis lingua musculorum, Ves. CoL Tertii paris linguae rnusculorum, Fed. Tertii paris propriorum linguae, Arant. Secundi paris linguae, -Cos. Styloglossus, Riol. Cowp. Doug. Sexti paris, oblique trahentis, styloglossi, Spig. Le styloglosse, PRIOR TO ALBINUS. 151 Stylohyoideus Tertii paris ossis referent! propriorum, Fes. Tertius hyoidis, Col. Tertii paris hyoidis ossis, YaL Cas. Tertii paris ossi hyoidi, ad lingua? rnotum destinatorum, Arant. Styloceratoides, Riot, Tertii paris, oblique sursum trahentis, sive styloceratohyoidei, Spig. Paris stylohyoidei, De Mar. Stylohyoideus, Cowp. Doug. Stylohyoides major, Sant. Le stylo-hyoi'dien, Win. Stylohyo'i'deus alter Stylo-chondrohyoidaeus, vel stylohyoidxus al. ter, Doug . An elegant small muscle, &c. Drake. De quo C&wper, Besides this I have frequently found another muscle, &c. in stylohy- oideo. Stylo-hyoides novus, Sant. Stylopharyngeus Quarti paris linguae, quod et faucibus adscribi potest, FaL Stylopharyngeus, Riol. Gowp. Valsalv. Morg. Doug. Sant. Tertii paris faucium, stylopharyngei, Spig . Le stylo-pharyngien, Win* 152 SYNONYMS Subclavius Primus in altero latere thoracem moventium, Fes. Primus thoracis musculus, Col. Yd. Qui sub clavicula occultatur, Fabric. Subclavius, Rlol. Spig. Cowp. Doug. Le souclavier, Win. Sublimis Primus digitos moventium, Fes. Quartus manus interior musculus, CoL Primus musculus, Arant. Sublimjs, Laur. RioL Digitorum secundi internodii flexor, Spig. Perforatus, Cowp. Doug. Le sublime, Hunauld. Le perfore, communement le sublime, Win. Subscapularis Sextus brachium moventium, Fes. Septimus humeri musculus, CoL Immersus, sive subscapularis, RioL Gircumagentium tertius, subscapularis, Spig. Subscapularis, Cowp. Doug. Le sous-scapulaire, Win. Supinator brevis Quartus radium peculiariter agentium, Fes* Nonus manus exterior musculus, Col. Brevis. supinator, RioL Supinatorurn secundus, Spig. Supinator radii brevis, Coivp, / PRIOR. TO ALB1NUS. Supinator brevis, Doug . Le court, ou petit supinateur, Win. Supinator longus Quatuor radium peculiariter agentium secun- dus, Fes. Octavus manus exterior musculus, longissimus nuncupatus, Col. Longus supinator, Riol. Supinatorum primus, sive longior, Spig. Supinator radii longus, Cowp. Supinator longus, Doug. Le long ou grand supinateur, Win, Supraspinatus Quintus brachium moventium, Ves. Quintus humeri musculus, Col. Supraspinatus, Riol. Circumagentium humerum primus, super- scapularis superior, Spig . Supraspinatus, Cowp. Doug. Le sus-epineux, Win. Le sur-epineux, Ejusd. Temporalis Inferiorem maxillam moventium primus alte- rius lateris musculus, seu temporalis, Ves. Temporalis, Col. Fal. Arant. Riol. Spig. Cowp. Doug. Sant. Le crotaphite, Win. Tensor tympani Musculus ossiculi malleo comparati, Eust. 154 SYNONYMS Musculus ab Eustachio obsertatus, Arant* Musculus malleum ad incudem movens, Fa* brie. Internus, E/usd. Spig* Auris internee secundus, Cos. Qui ab ojse cuneiformi prognatus, Ejufd. Alter iaternus, et in concha latitans, RioL Musculus interims auris, Motin. Internus mallei, ScheUiam. Le second de ceux qui apartiennent au mar- teau, et Pexterne, Du Per. Internus auris, Cowp. Musculus majoris processus, Falsalv* Internus auris Eustach. Doug . Le monogastrique, Vieuss. Le muscle interne du marteau, Win. Tensor vaginae femoris Est pars carnea sexti tibiarn moventium, Ves. Eadem .sexti tibiae rnusculi, Col. Membranosi, RioL Cowp, Doug. Extendentium tibiam primi, membranosi, musculus lati tendinis, Spig., Le muscle aponeurotique, ou muscle du fas- cia lata, Win. Le muscle de la bande large, ou du fascia lata, Ljusd. Teres major Tertius brachium movetitium, Tertius humeri musculus, Col. Rotuiidus major, JRiet* PRIOR TO ALBINUS. 155 Deprimens humcrum rotundas, Teres major, Cowp. Doug. Le grand rond, Win. Teres minor Octavus movens burner um, Fa!. Vid. quas re- spondit Ves. in Exam. Rotundus minor, Riol. Musculus peculiaris, a nemine adhuc anno- tatus, cujus inventionem Placentinus sibi tribuebat, Cas. apud Spig. Teres minor, Cowp. Doug. Le petit rond, Win. Tbyreoarytamoideus Propriorum laryngis nonus et decimus, Fes. Musculorum laryngis, qui ipsius proprii di- cuntur, quartus, CoL Ex propriis laryngis musculis, internorum se- cundi paris, FaL Ultimi musculi duo sunt, Ejusd. Flexio constringit clauditque rimulam, Ejusd. Quarti paris laryngis propriorum, Cas. duo a postica internae scutiformis parte, &c. Thyroarytaenoideus, Riol. Cowp. Morg. Doug, Paris thyroarytaenoidei, Spig. Thyro-arytaenoides, Sant. una cum thyro-epi- glottidaeo majore. Le thyroarytaenoidien, Dodart. Le thyro-arytenoidien, Win. una cum eo qui le thyro-epiglotique, Ejusd. 156- SYNONYM* Tibialis anticus Sextus pedem moventium, Ves. Primus musculus anterioris pcdis, Coi. Tibieus anticus, RloL Flectentium pedem primus, tibiaeus anticus, catenae musculus, Spig. Tibialis anticus, Cowp. Doug. Le jambier anterieur, IV in. Tibialis posicus Quintus pedem moventium, Ves. Quintus tibiae musculus, CoL Quintus movens pedem, Fat. Tibieus posticus, Riot. Oblique moventium pedem primus, adducens pedem, nautjcus, tibiaeus posticus, Spig. Tibialis posticus, Cowp. Doug. Heist. Le jambietf posterjeur, Win. Trachelomastoi'deus Secundi pans caput moventium musculus tertius, Ves. Pars secundi musculi capitis, CoL Tertius movens caput, Fal^ Eorum, qui (duos, a recentioribus anatomicis ante alios descriptos) sequuntur, portio, quae externam sedem occupat, Eust* Pars complexi, Riot. Cowp. 1694* Tertius musculus trigemini, aut compositi* Spig. Trcahelomastoidseus, seu capitis par tertium, FaL Doug. Gwp. 1724. PRIOR TO AlBINUS. 157 Le petit complexus, ou mastoidien lateral, Win. Tragicus Musculus tragi, Vdsdv. Sant. Transversalis cervicis . Quintus et sextus dorsum moventium, Ves. Tertius cervicis musculus, Col. Secundi paris dorsi musculorun principiura prius, FaL Transversarius, Riol. Transversalis, Spig. Le grand tranversaire du col, Win. Transversus abdominis Transversus, Ves. Tab. Riol. Spig. Morg. Sant, Transversalis, Col. Cowp. Doug. Le transverse, Win. Transversus auriculx Sunt fibrse transversae in gibbo auriculae, Vd- salv. Fibrae, quse in convexa conchae parte, Sant. Transversus pedis Est novus musculus. Julius Placentinus Pata- vinus, Chir. et Anat. insignis, primus de hoc ad nos scripsit, Bauhin. Decimus tertius digitorum pedis, Ejusd. Musculus transversus, Riol. Transversalis, Cos. Morg. Transversalis pedis, Cowp. Transversalis pedis Jul. Gas. Placent. Doug. Le transversal des orteils, Win. 3 158 SYNONYMS Transversus perinosi An est alius musculus ad vjrgae latus minimus, Stephan. ? Levator ani parvus, RioL ? Transversus, T. Earth. . Transversalis penis, Cowp. Heist. Le dilatateur, qui part de la partie interieure de la tuberosite, Lift re. Levator ani parvus, seu externus, Riol. Doug . Penis musculus transversus, Morg. Transversalis, Sant. Transversalis urethrae, Morg. An le transversale de Purethre, et le trans- verse, Win. In fcemina transversalis, Sant. Transversalis perinaei alter Urethrae elevator, sive ejaculator, Sant. An le prostatique inferieur, Win. ? In fcemina est depressor urethrae, . Sant. Triangularis sterni Sextus in altero latere thoracem hominis mo- ventium, Ves. Sextus thoracis, Col. Fal. Qui internae sterni sedi apponitur, Fabric. Triangularis et pectoralis internus, RioL Triangularis, '^teno. Be Mar. Ccivp. Doug. Sternocostales, yerheyen. Sant. Les sterno-costaux, communement le triangu- laire du sternum, Win. Triceps bracbii Lvngus est, cubitum exteuden|jum primus, Ves. PRIOR TO AtBINUS. Tertius cubiti, Col. Longus, RioL Le grand ancpne, Win. Brevis est, tertius cubitum extendentium, Vies. Brevis, RioL Os cubiti extendentium secundus, Spig. L'ancone externe, Win. Brachialis cxtemus, carnosa pars, qua primus extendentium augetur, quern secundum constituere licet, Ves* Brachieus externus Riol, Cowp. Brachialis externus, Dong. L'ancone interne, Win. Brevis cum brachiali externo, quartus cubiti, Col. Longus una cum brachiali externo, est os cubiti extendentium primus, Spig. Longus una cum brevi, Gemellus, Cowp. Biceps externus, Doug . Triceps totus, triceps cubiti, extensor cubiti magnus, triplici principio natus, Doug. . Vide cubiti extensores, Morg. V Vastus externus Septimus tibiam moventium, Yes. Septimus tibiae musculus, Col. Vastus externus, RioL Cowp. Doug. Extendentium tibiam tertius, vastus extrnus, 160 SYNONYM^ Le vaste externe, Win. Vastus interims Pars octavi tibiam moventium, Ves. Pars octavi tibiae musculi, Col. Vastus interims, RioL Cowp. Doug. Pars extendentium tibiam quarti, vasti intern^ Spig. Le vaste interne, Win. U Ulnaris externus Tertius brachiale moventium, Ves. Sextus manus exterior musculus, CoL , Cubiteus externus, RioL Extendentium (carpum) interior, Spig. Extensor carpi ulnaris, Cowp. Doug. Le cubital externe, Win. Ulnaris internus Primus brachiale moventium, Ves. Secundus musculus interior manus, CoL Cubiteus internus, RioL Flectentium (carpum) interior, Spig. Flexor carpi ulnaris, Cowp. Doug. Le cubital interne, Win. Zygomaticus major Est unus ex quatuor musculorum labris pro- priorum duobus primis, Ves. Zygomaticus, RioL Doug. Cowp. 1724 Morg. PRIOR TO ALBINUS. Primi paris, sive attollentis labium superius, Spig . baud dubi'e. Zugomatieus, Cowp. 1694. Zygomaticus major, Sant. Le grand zygomatique, Win* An fasciculi ejus sub pingui labii inferioris excurrentes, sunt eorrugatoris, seu protruspw ris, ordo exterior, Sant. ? Zygomaticus minor Est the shortest fleshy slip, Doug, in elevato^ re labii superioris proprio. De quo Morg. Sic ab osse jugali fasciculupa fibrarum non contemnendum, &c. Zygomaticus minor, Sant. Le petit zygorAatique, Win, PART II, CONTAINING THE MUSCLES PECULIARLY BELONGING TO THE OSSEOUS STRUCTURE, ARRANGED ACCORDING TO THE SEVERAL BONES TO WHICH THEY ARE AT- TACHED ; WITH GENERAL OBSERVATIONS ON THE DIFFERENT PARTS CONSTITUTING A MUS- CLE, AND GENERAL OBSERVATIONS ON MUSCU- LAR ACTION* T r THE MUSCLES ARRANGED ACCORDING TO THE BONES, CHAPTER L T- HE following Table contains all the .muscles con- nected with the skeleton by origin or insertion. In the middle column the bones are arranged in the usual order of demonstration ; the series com- mencing with the bones of the cranium, and pro- ceeding regularly through the bones of the face,' the neck, and the ti;unk, to those of the atlantal and sacral extremities ; the single bones, the pairs, and the classes, are each followed by the muscles attached to them. The names of the muscles are either iri Roman or Italic characters : the Roman characters express the muscles which are connect- ed with the bones by insertion ; the Italic charac- ters, the muscles which are connected by origin. When any of the muscles have other origins, they are to be found'inthe first column towards the left in Italic characters ; when other insertions, in the 166 THE MUSCLES ARRANGED third column towards the eight in Roman charac- ters. Upon a plan somewhat analogous, the celebrated Cowper arranged the muscles according to the bones in which they are inserted ; and the accurate Winslow, according to the bones to which they are attached, without the distinction into origin and insertion, which he disliked*. That distinction, however, is preserved in the following Table ; not indeed on account of its accuracy, but on account of its general expediency, which more than com- pensates for any of those erroneous conclusions that the young anatomist, when not sufficiently in- formed of the circumstances, may chanee to draw from it. As the tables of both Cowper and Winslow arc defective in point of enumeration, and as they ex- hibit no more at a time than one-half of the mus- cular attachments, they present not to the eye the connection of bones through the medium of mus- cles, nor assist the physiologist in explaining their functions. The use of this table to the nat6rnist scarce- ly requires any explanation. On a cursory glance it presents to his view a number of cir- cumstances not easily remembered, and which, though always connected in nature, are not very See page 32, ACCORDING TO THE BONES. " 167 *ften associated in the memory. It explains satis- factorily many of the sympathies that exist between the motions of distant parts connected by muscular attachments or functipns: As, for instance, how pain, arising from a luxation of the humerus, should, upon motion, extend to the sternum, the back, and the loins ; and how pain, arising from in- juries of the loins, should be affected by motions of :the humerus when any powerful or extensive operation of the Latissimus dorsi is required. It may likewise be useful in suggesting hints about the modes of reducing bones after cases of luxation or fracture ; about placing the parts in the most easy and natural position after reduction; about what motions should be avoided, wha*t should be allowed, what should be left to the pati- ent himself, and what should necessarily be check- ed by bandages, and how these bandages ought to be applied. If the young anatomist should not readily per- ceive how this kind of knowledge is to be acquired from examining the Table, he will be assisted by the explanations that are afterwards given of the several motions ; as this Table and these explana- tions are intended to reflect a mutual light upon one another. 158 THE MCSCLES ARRAivCEO I -51 1 Ills CX. C #5 g SP ny o co a e .2 o 2 'I . -i Ak> ' CXi oo rt bO !73 '5'38 g r& cri Q i ^ 6 5 fi ^ S S O ?3 ^5 ^ i= s I -1 T3 3 3 t> o o * 02 ^< i S i . ., l i - I : i 1 1 r s i ^S t* ^^-^00 3 _| S > 3- I ^ ^^ THE MUSCLES ARRANGED W 1 1 i g 1 S \ < CL, S 2 o X fft insores tympar S 'S u Jt JCUDES. 'uibus musculi Q S .-2 51 r-. C8 O 00 u o CO O *S co* t J 4- 1 t- tS ''* II ACCORDING TO THE BONES. ITT' w 3 S C o <*> .-a'* 3 *i 3 co ^ O O co a e 5 -5 C S S g w il Pi P .G . _ . ^ce oj .jo .2 5^ *5u, 'o. *& ex, ca r3 J!p ro ro U u S o u c&p 1 '1 '^ P- tn t . r 5 .a > r . o S "s ^o constr i | * S * * * 4 C 2 C vT Nil ^ -s . t: THE MUSCLES ARRANGED **% 1 % -o . - & % JS J2 I 04 3 | tin ii, * * fr.Ht ^ 2 '& & feVg | a j o a ! fffl *; s $ r s s addu -i 8 i li *! S sS .8 ACCORDING TO THE BONES, .< 3 C ;=! 3 C t> S 174 THE MUSCLES ARRANGED ACCORDING TO THE BONES, c -S S 1 ii 3 -^ A^ a 8 II a, \ g ll 8 8 176 THE MUSCLES w oS .5 o O ,0 1 1 o o o o Temporalea. 1 es, Q> "o O to to 10 * ^ CO ^ J-. se .- .J 3 4 :s HI I $ i s^ ^ -!> I S>H 6 t & ^r w g tfj CO * ^ w to * *2 ' "^ >* 1 VERTEBR. u *5o c o ^4 1 1 FROCESSU Interspinalt Multifidi sj c "s* V CO ^ 1 > ^ 1 "^ "5 1 t ts % . 1 1 * i 5 '3 5 ^l 'H ^ 4 "w ^ i; 4S 1 1 4 ^ "S t J ^ ^C | 4 v i 4 | 1 ^ ' ? i i *! 8 S ** "^ e ^ 4 i !tJ S ii d .0 .J S % ACCORDING TO THE BONES. 179 I .* .* 9 o u o .ti .tj .-a S .o* o .0, ; s s s rf 1 m i-^l O "C (X 1 2 :~ 1 4$ J *O C * ' i !l . JJ;! 65 B S I | "| s '3 -5 ! I i i -E. a 1 HS CO H U O 6Q ? .! 1- g .; -5 44 4 S " li B 3 a a i i H S "S 5 J g ' ^S -2 ^ b ja III S 5 S ^44 I Ma 180 THE MUSCLES ARRANGES 1 .5 s g **3 2 P. 8 o 6 2 -S * 3 O PL; o S a o fi I q 1 i? W a I * *> t> a s >-] | i g s *s o tt ^ c I li ^ i ;*"* \ C/3 1 1 CO to *S W u o (fi e 'a< 02 o- an . rj> *^j u v- CO ^ .s K /.2 * Vi M 1 i " li 4 *- .5 ^3 -p ACCORDING TO THE BONES, 181 1 1 o w * -8 'e ' ? r\ *^ CO 00 CO Jill r^. r\. x^ ,^i CO OD O f\ co O 8 P 9 2 .2 o o Ctf LS c o ^ w ^ I i 1 a .1 o tm I J PH M 1 1 C ^Q '&. 3 * II ill VERTEBRX *j 3 ? I'S i-. H .* .2 .^ -^ 1 1 8 -i ^ 1 1 i THE MU3CLES ARRANGED PROGESSUS Spitf ALES , lumlorum. Multifidi spinse. * o 1 1. Serf at I postlci infer 'tore t. spinales sacri. Sacrolumbales cum accesw anwsrsi lum- O) ^ . N Jl ^ ^. ^ 3 .1^ V, * * $ ftj| Q . > <- 1> S; 4 H 1 5'* * < i^ * ^ Qj g | ^ 6 o "o I s .4 :S| n i 1 *s o ~3 S -1 oi ' s c ^o 2 'IS S^ i o s . c .' '8 i ^3 . *3 j- 6 . JT *> w o *tn o> ? W W 2 o *; 2 o' o 3 u V 7 Q O O . 5i S wi "< t*J * * ^ < | S - ^ "B "1 ^. 1 51 * S ^ .4 i- H 2 3 1 ^ i a ' -1 " '3 1 1 i, '11 ai ^J o ?i cy ^ eg ^ g I ^ 1 *1 1. I! -cP il ^ .? '^ 1 -i s ** 5 i-J ;a Jl *^ ^ ^ ^ 'JJ * %J ^J *** . .& 5 4* i." ' si' 1 'I 1 Qt 'S <3 ' S ^ ^ ACCORDING TO THE BONES. 183 \* 1 s ^ o I I 1 i & 5 "I .5 3 fcJ3 * rt o a H 5 s S 2 u " 3 S S S o *< o a CESSUS SP O^ f^ dor abd Olllqui ii il :IJ 15 Kj 4 C 5 !^ S Cjt5 4 ^ ^ -5 'tit 1 ilil * 184 THE MUSCLES ARRANGED re n s .ics o C*5 !D 1/5 % U O & O S 55 Vj X w . 3* g | >H .~; s 1 1 ! c> 1 <5 4 c G o o u o CJ c3 Curvato; Levator Nj w H '5 CO 3 O o ~ 4 ^ h S i ^g ^ d s .1 - 4 ^ ACCORDING TO THE BONES, 185 N 6-1 7J Js *j3 a .e J8 i>5 "3 *5- y 0> 'i 1 offi ^ ^3 13 as -S 2 rt lores. ri i CO S 1 l .2 CO j E en [D i2 CO u ^Q ra > c .2 g 2 "s , 3 ffl I iiii . IliiiiJiw SK . . s * > * o -^ B a -i ii i li HI | i ? i ^ d i is &, Q O 3 . CJ ^ _Q -W g (5 :! ^ "S '? 1 : H ^ & a i ij r* f -^ ip I ^ <0 i< ^ -ts . 3 .^5 ^ 5 Q TO THE EONff, _0 ,0 (9 ftj (X (3 U O 13 u i si 1 1 I 1 I i I I S : | s; K E S B .K p & z Js 5 : 183 THE MUSCLES ARRANGED B B g s o o *a 'a o o 'i 1 U B to co a* a* (3 o 55 5 a 'O 553-5 ! I* I* ! 9*.^ - 4 4 4 ? o *3 <^ ** '-2 ? ACCORB1NC TO THE BONE3. S IS -0 J* , t s 6 | 8 | g S g *_. OJ S B"S S -X3 O CO 1 1 CO S b 1 .1 s a g i^ 1 * *\ S t2 . 1 . sf 5 *! i! CO . +* 1 'I ** ^ is V. C W CJ "^ * g S & S i 5 ftlKi I "& \ * C9 ^ <9 dbductores t s i . 11 f*} | t~5 m C Ji vi "** J ^ 3 3- g fl 'SL .S -5 g ^ 2 !i ^ $* 2 1^ pfej' fa 00 CO -p^ f^ O Extensors '^i I 1 1 i l! Q "a ; i ii e^J t ^l.- sis E,3 ri II ill i i! i 192 THE MUSCLES ARRANGED S.3 S o 3 *n "! ^J > & 3 e s* S e 2 5 < 1 ACCORDING TO THE BtfNES. S 9 193 8. 8. C=! O 0, ^ il . 'S bo bo c c x'5 s a s ^ I 8 K 5 I ! a I |1 I * I it!! ^*"^ II 3 T II 8 i - ktt I i ^ 9 j fi W N J94 THE MUSCLES ARRANGED bO " 3 "** 11 1 & 3 rt i * a w to S * O "^ hi -< J- O rt X J5 I > ^4 ^ ^ fj 4 ^ v J k", 1 O s S B ^ ^ M u x S w = si EE O fi 5-1 ^ SoS I J-11 co PL, - w ,_ <_ 3 a . e ^ Q *~ a ^ a 3^-2 c s | S & 2 3 g C Q .^> .L* ACCORDING to THE BONES. i 'i i 4" HI. -5 ^ ^ I-L^ ivj , H KH O p N M 1 ( H Pi Radiales externi breviore Interossei. 2 ! -i.a .-# II u ddductores poUicum. 1 _ 1 Q 1 . C 2n *> 5 c 5 1 '"^ ' 9 * t; 5^i"| S | S ~* i O '^ 1 i Q 3 ^s v^ ^5 *ij ffi T5 -2 ^ i 2 V S ^j S ~ % rg T3 V IJ If CO ' I . M 3 8 S g g 3 S O 3 S * 2 4 S ' -i Jr; 3S i s K 3 S << . c K * ** c .1 I Q* *3 >4 L.J TO E O p O *T3 4-> w j . 2*2 W W 1 s s "to o M tt s 2y ll 111 K Q p CJ ^ fe N -iz 1 -1 '1 i s 1 m i Q ". "1 k, a '*p* 4 4 "i ^7 ^ 1 externi 1 S J S J 1 1 1 1 ! ^ S 1 <-> "1 S 4 a -^" *! Q 1 i 1 1 i n : -|i ^ Co i i , o A <^ '* A -I | | 1 | ^s ** & *^ a ^ i t n g 1 ^ IK te . s 9 B * ^ e SJ S- I I 4 li ACCORDING TO THE 201 1 1 5 I ;.: ^ fSJ H H Jj E o 1 1 1 1 i i i i wp^eEEEg V O J 4> O U t ^NHN^fS^fS CO w t t t ^ N sj THE MUSCLES ARRANGED 2 2 ^ o o o i 5 5 J 6 s e S ii - . ** | S 1 L - * to b c 1 u a V. ! J2 JS . S S S 'S ^ - i. bo O O O re Si I g S? liiliOi THE MUSCLES ARRANGES Metatarsi rimorum, S 6 B Bb c internum, ignorum, C 'e i o t 4_ 4J ;_ S S 3 O ^*J [So o "'O 2 o *s c 3 o ;> 'o 0< 3 S> 2 c c Ct5 TO 1 a O o 'O S n* < r* rt 3 1*4 p , JJ P.I o i g G _O ^ rs *1 O O '-i S- .^ - ^ -. Q. O^ r|^ THE MUSCLES ARRANGED I'!' 6 g 'So o I o 3 J-. o 2 "g 'O 3 2 b/5 c 6 C "c G *n 3 > > ^ 0* 2 ^ V- o bO *^ *:j ^ c c C2 S 5 c [So .3 v CO CA o 2 *5 S 3 S (Tj IS- 3 -2 13 * H R H ^ ^ 1 1 i i 1 1 ( i^r' i * ^-2 .ssorn. < | itt 5 t < M - | 8 P^ < s IS | -< O G c S Extensorcs brews d ^ z if IS ? 5; Mas S .? i f^ * l-fs i ia ii O i4 S 1 & Q J 1 3 * 5 S 1 ^ } * 10 THE MUSCLES ARRANGED ACCORDING TO THE BONES. 1 i 812 THE MUSCLES ARRANGED phalanges t 1 c* III "11 | *^A Ofc O ^ * & go ^5 I i i ACCORDING TO THE BONES. 213 '-* a ti fc o 2 2.S i *!='! fc- .s ^ CO IB iil't 4 s c <* ~5 *o S'o 2 S a, M gild !^ H S ~ . 8 W c 2 CX. Of 6 3 bO Cb cl Jl&lj 1 < W ^ 3 1 1J 2 K P4 p u .3 o i | S3 I fi p^l 1 s .*2 H! .to < 5 H . S3 A | O f 1 - -3 '1 8, > 'o cu t Q g ,^ a, ** J g s S to o n o o *- 7+ x- 1 M o 1 1 g | M SJ fjl Q. s S g g X Ji W K is 1 2'5 3 ^^ 1 ^1 1 g S H r i !?& ^ 1 ll ^. Ligament a asi sustinentta. Cuboidea. C Nonnunquam tertiiy secund*. ria Pertneorwn / \ 5 ^i| s.i 8'53 2 |ll I 5 R h ^ |Hs ^3 1 jj ^ ^ 214 THE MUSCLES ARRANGED Tendmes Flexorum longorutn, Teadinei Flexorum longorum ft a i S s a 3 s ffi x >4 w w S g ts 1 * ^ 4 S ta t/5 P ^ *:l ^ O O J5 * 1 X *C 4U cn -P v M II ACCORDING TO THE BONES, SIS I li 8* 14 2 '5 1 i 217 3 CHAP. II. GENERAL OBSERVATIONS. jVfuscLES are the organs which change, regulate, and fix the positions and attitudes of the system, and which are directly or indirectly concerned in all the more conspicuous motions of the solids and fluids. In these numerous and important operations they exhibit phenomena peculiar to themselves, and which cannot be traced to gravity or impulse, to -elasticity or to chemical attraction. They pro- duce their effect, whether it be a state of motion or rest, by contracting their fibres in consequence of stimulants ; while the stimulants, whether che- mical, mechanical, or vital, seem to act through the medium of a nervous energy. They are not restricted to any length, breadth, or, thickness ; to any form, magnitude, or colour ; though every one belonging to a pair resemble its fellow, and all the muscles of one individual be analogous in form, colour, attachment, and func- tion, to the correspondent muscles of another of the >same species. They are not found of any one homogeneous GENERAL OBSERVATIONS, substance, but composed of carneous and tendinous fibres, interspersed every where with cellular merrir feme, and the ramifications of arteries, veins, ab r sorbents, and nerves, all of them alive, and all of them irritable. THE CARNEOUS FIBRES. THE carneous fibres constitute ^for^. They sel- dom or never appear single, but are collected into small fasciculi, that unite to form larger fasciculi ; which larger fasciculi being united, form the col- lections which, with their tendinous fibres, &c. we call muscles^ and which we distinguish by proper names. The carneous fibres are all sensible to stimulants of one kind or another; and being the only parts that contract in obedience to the will, or in con- sequence of stimulants operating regularly, they constitute the distinguishing character of muscles. As they derive their principal power from a vital source, the change produced upon them by death is sudden and obvious. Hence the muscles that, when living, could have ruptured their tendons, luxated the bones, or broken them to pieces, can scarcely, when dead, if it were not for their ten- dons, their cellular membrane, and the ramifica- tions of the sanguiferous and absorbent systems, support their own weight. In the living state^ it is obvious, however, that their strength must yary, and in a great measure depend on the naturq &1NERAL OBSERVATIONS, 2I and degree of the energy communicated. In the, voluntary muscles, that energy, to a certain ex- tent, is varied at pleasure : and hence it is, that, by a simple act of the will, the smaller muscles are frequently observed to overcome the larger ; the flexors to overcome the extensors ; the extensors the flexors ; and that both, when we choose, are obser- ved to balance their relative forces, and to fix the intended position of the parts. Yet the influence of the will is nothing, compared to the influence of instinct, emotion, and passion, to which the will is frequently subservient. These often affect the whole of the muscles, and through their medium alter the secretions. It is this connection between muscular action and the vital powers, that explains those extraordi- nary changes which take place in the system of credulous persons, whose fancies are under the im- pressions of witchcraft, insanity, galvanism, of ani- mal magnetism, or animal electricity. And the same connection likewise explains how our mus- cular strength is varied by the states of sickness and health ; and how our exertions are more or less vigorous and extensive, continued for a longer or a shorter period, and attended with greater or with less fatigue, in proportion as the mind happens to be influenced by the exhilarating or depressing passions. The degrees of force thus arising from volition, not only being different in different muscles, but in GENERAL OBSERVATIONS. 1 different parts of the same muscle at the same time, as may be seen in the common flexors and the com- mon extensors of the fingers and the toes, have with justice been regarded, not only as proofs of the singular influence, but superintendence, of the vital principle in the animal system. They are proofs, ho wever, neither stronger nor clearer, nor of a much more frequent occurrence, than what we ob- serve in those cases where chemical and mechani- cal stimulants are applied so as to excite painful sensations. In these instances, it is often not the muscle more immediately -affected that is thrown into action, but those muscles, whether distant or near, that are best calculated, by their joint opera- tion, to alleviate the feeling, to remove the cause by which it is occasioned, or to withdraw the part from the injury to which it is exposed. Thus when the fauces are tickled with a feather, it is not the muscles most directly affected that are thrown into action, but the stomach from a distance gives the alarm; when instantly the abdominal muscles, and diaphragm, and all the muscles concerned in res- piration, hasten to unite in the general support of the common cause : not indeed as if they were the only organs interested, but the only organs that arc able to bring the speediest assistance in such an emergency. OBSERVATIONS. THE TENDINOUS FIBRES. THE tendinous fibres constitute tendons, or those parts which in common language are denominated sinews. They are quite insensible in the healthy state, are somewhat elastic, but never contract, like the carneous fasciculi, in consequence of stimu- lants obedient to the will or operating regularly. In their general appearance they bear a resem- blance to some of the ligaments attached to the bones, and indeed are the media through which the carneous fasciculi in general are attached to the skeleton. In all the muscles of the same name belonging to a species, they have a similar form and situation, and are generally thought to bear a much greater proportion to the carneous fasciculi in the muscles of the active, vigorous, and adult, than in those of the indolent, feeble, and young. In the human body, they occupy the spaces where the carneous fibres could not be admitted without in^ creasing both the weight and the bulk of the parts, requiring at the same time a considerable increase in the surface of attachment, and a change in the form and magnitude of the bones ; the spaces like- wise where the forces of the several carneous fibres are most concentrated ; the spaces where either the pressure or friction would be injurious to the car- neous fibres, and to that size of nerves and of ves- sels with which they must always be necessarily ac- 4 222 CENERAt OBSERVATION*. companied. As to their connection with the carne- us fibres, the carneous fibres are sometimes attached to them at their extremities, sometimes at one side, sometimes at both ; sometimes at one angle, some- times at another; but always according to certain specific and determinate laws, as they regularly observe the same form, course, and attachment, in every muscle of the same name belonging to the species. By this contrivance, independently of bulk, not only is the strength and the form of the muscles, but their force, their extent, and their mode of action, in many respects, wonderfully varied to suit the several situations and circum- stances where their functions are required. As some muscles (for I speak not here of the contradictory and various reports that are founded on microscopic observations) ; as some muscles, so far as they appear to the naked eye, are without tendons, we cannot suppose that tendons form ari essential character of the muscular system; though, by their variety of form and situation, they are well calculated, with uses, attachments, and other cir- cumstances, to constitute those secondary characters by which one muscle is distinguished frem another* In some muscles, the tendinous fibres are closely interwoven, as it were, with the carneous ; in others, they form 2, tendon in- the middle be- tween the two fleshy extremities ; in a third vari- ety, a part of the tendon is made to divide the mus- cle longitudinally, while the carneous fibres e OBSERVATIONS. Obliquely on each side * ; in a fourth variety, the carneous fibres enter the tendon on one side only j in a fifth variety, they begin with a tendon to- wards their origin ; in a sixth, they have a tendon towards their insertion ; in a seventh, they have a tendon at origin and insertion ; in an eighth, they have several tendons in these situations ; and in many muscles the varieties are mixed. As the strength of the tendons, like that of the bones, ligaments, membranes, and cartilages, de- pends but little, after they are farmed, on the ner- vous energy, the changes induced upon them by death are slow and imperceptible, in comparison of those which are induced on the carneous fasciculi : stnd hence we observe, that the tendinous portion of every muscle is decidedly the strongest in the dead Lody, although often found to be the weakest ia the living. * Although, from the line that runs longitudinally, dividing the rows of carneous fibres, these muscles have been named pen- ^aiform, there are other circumstances that characterise them. Besides what is common to many a muscle, a tendon botfe at origin and insertion, they seem to have regularly a tendi- nous expansion alternately on the dermal and the central aspect $ fo that whenever they are found to be tendinous on one aspect, in the part which is opposite of the other aspect they arc found to be carneous, and vice GENERAL OBSERVATIONS*,* THE CELLULAR MEMBRANE. THE cellular membrane, which is more or les$ dense and elastic according to circumstances, is interposed between every muscle, between every fasciculus and every fibre, so far as we can trace them. It envelopes every artery, every vein, ab- sorbent, and nerve ; and at the time it maintains a connection, it preserves a distinction, officiating at once as a fascia, a ligament, and a mucous gland. In this last capacity it lubricates the parts with which it is in contact, diminishes friction, facili- tates motion, prevents adhesions, and, where it is necessary, contains a quantity of oil in its cells^ in order to mix it with the mucous secretions. It is also interposed between the integuments and the muscles beneath, where it generally con*- tains a large quantity of adipose matter, which, from being a bad conductor of caloric, contributes to preserve the temperature that is necessary for the due performance of the several functions. It con- tains this matter in large quantities, where the temperature is defective for want of exercise, as in indolent persons and very young children; in large quantities, where the temperature is likely to prove defective from the natural state of the circulation, as ori the sternal part of the abdomen, where the tendons, as usual, are supplied with but small bran- ches of arteries ; in large quantities, where it is af- GENERAL OBSERVATIONS. terwards to be used as nourishment, as in many a-, nimals that are regularly subjected to the torpid state, that lie down fat in the end of autumn, sleep through the winter, and awaken emaciated upon the genial approach of spring. It has often been remarked, that fat sheep support abstinence bet- tcr than the lean; that some buried in the snow for weeks have been taken out alive ; and that others have lived, cateris paribus, longer or shorter, pro- portioned to the quantity of their adipose substance. That this substance is consumed in disease, when we are incapable of taking the regular supplies of food, or converting it into chyle, is a fact too ge- nerally known to require proof: that it is absorbed in a state of health, is far from improbable. It is a reservoir from which the system may be so far supplied in a uniform manner, and by which the changes arising from occasional and irregular diet may, to a certain extent, be counteracted. From the extensive and general distribution of the cellular membrane ; from its accompanying every artery, vein, absorbent, and nerve, and inter- mixing with every organ on which these are rami- fied ; from its various degrees of elasticity and den- sity in different situations and different regions, it is not unlikely that it performs some general func-* tion necessary to every part of the system, but va- ried somewhat according to circumstances. Dif- ferent organs secrete and assimilate different sub- stances from the sanguineous fluid ; different nerves P- 226 GENERAL OBSERVATIONS, and different vessels have different offices : And as nerves and^ vessels are all enveloped in cellular membrane, it is not improbable that in all it in- fluences their action, and thereby contributes, with other causes, to accommodate the arteries, the veins, the absorbents, the nerves, and the organs on which they are ramified, to perform each their appropriate modifications of function. It is well known that diseased appearances are often confined, to the cellular membrane; and that where such ap- pearances exist in any of the organs, or around a, vein, an artery, or a nerve, they exhibit the symp-* toms of a morbid action 1 *, THE ARTERIES. THE larger branches of arterial vessels that are ramified in the muscles contain red blood; the smallest branches, particularly in the tendons, contain only a part that is transparent. AH are meant to convey nourishment ; and as no fluid is known to exude through inorganic pores in the living body, some of their ramuli must terminate in the carneous or tendinous fibres, where they de- posite a part of their contents, that by the process of assimilation is retained, and assumes the cha- racter and appearance of the parts with which it is united. Arteries are elastic in their -longitudinal and * Vide Anatomic Generale, par Fra. Xavier Bichat. Tomf , du Systeme Cellulaire. GENERAL OBSERVATIONS- 227 transverse directions, and have different diame- ters at different times, according to the quantity of blood they contain, and the force of the heart by which that is propelled. In the living body they are always full ; though, from the interrupted sup- plies of the heart, the blood does not flow through their larger branches in a uniform stream ; wave is supposed to succeed wave : and this notion is said to be strengthened from the jets of an artery when it is opened, and from the pulsation of those which are felt towards the surface. In the small- er branches, the undulatory motion is supposed to cease, although, when the eye is assisted by the microscope, we see globule following after globule in the web between the toes of a frog ; and altho' in paronychia, we are, by a kind of internal feel- ing, made as conscious of pulsation at the point of a finger, as we are by the touch of the radial artery, where it beats near the carpus. The ques- tion is here, Is the sense of touch and unaided sight the only evidence by which we can form an opi* nion on the subject ? As for the expression undulatory motion, it is not correct ; it transports the fancy t6 some watery ex- panse, where it sees wave following after wave in numerous succession at the same time. In thq blood each wave is observed to cease ere another begins : It arises from the contraction of the heart throwing an additional quantity of fluid into the arteries at one extremity, and displacing a propor- P2 ENi:fcAL OBSERVATION*. tional quantity at the other : The impulse is felt through all the parts of the system at once, simi- lar to what we often observe in the action of a pump, where the water does not merely flow, but is forced by repeated strokes, through a narrow aper- ture; and the tendency of the pipe to occasion a re- coil, and to throw it backwards, resisted by valves. The waves or pulses which are thus produced by the action of the heart arc varied in force, velocity, mag- nitude, the regular and irregular order of succession ; and these differences being variously combined with several kinds of vibratory motion, occasion a part of that almost infinite variety of effect, from which some, by feeling the artery at the wrist, at- tempt to ascertain the nature of disease, to predict its duration, its periods of change, and its mode of termination. If we attend to the course of the arteries, we shall not find them always running in a straight line from their commencement to their termination, but shall generally i find them in those situations Where they are best protected and secured, and arc best enabled to perform their functions with the least chance of interruption or danger. If we attend to their ramifications, we shall usu- ally find, that they are sent to parts in the vicinity; or if they be sent to a greater distance, that they undergo changes in their course that require the length of space which they occupy ; that those si- tuations in which they originate are more favour- abel for receiving the blood thaa those which are GINERAX OJBSEHVATIONI* near ; that the longest course is decidedly the $a* fest ; or that the parts to which they are destined require to be furnished with branches proceeding from different quarters, in order to insure at all times a regular supply; a circumstance, by the way, which seems partly to explain those commu- nications that every where take place among vas- cular branches of the same class, whether they be* arteries, veins, or absorbents. 1 have said partly ; as these plexuses, with the different angles at which the branches arise from the trunks, with the diffe- rent modes of division and union, with the diffe- rent convolutions and serpentine windings, con- tribute also, not only to modify the action of the heart on the several fluids, but likewise to accommo- date the state of the fluids to the nature of the or- gans, to that of the secretions, and the other fune^ lions in which organs are employed. THE VEINS. As the blood cannot return to the heart by the way it goes out, on account of the valves placed at ihe commencement of the two great arteries > it pro- ceeds onward till it enters the veins. Now the veins, in a vague and general sense, may be consi- dered as. the arteries reflected with a change of di- ameter, appearance, and structure, to convey the blood in a retrograde course, whether from the lungs or the system at large, back to the heart. In the human species the heart is situated iu the 230 GENERAL OBSERVATIONS,, region of the thorax, enclosed in a capsule, and this capsule surrounded by the lungs on the sternal, .the dorsal, and the lateral aspects. It is formed of a strong and intricate texture of muscular fibres : jjt has two cavities that are named ventricles, with an imperforated septum between them. By a la- teral opening, each of the ventricles receives b]ood from a venous reservoir of a muscular structure, that is termed a sinus. By another opening to- wards the base, they afterwards propel it into an artery ; the entrance at the side, and the exit at the base, being furnished with valves to prevent its return. The blood, changed by the action of the lungs and the air that is inspired, is collected by veins, which, after a number of reiterated unions, at last terminate in four large trunks : These trunks dis- charge their blood into what is called the systemic sinus ; that sinus, by muscular contraction throws it into the systemic ventricle ; the systemic ven- tricle, with greater force, throws it afterwards into % the aorta ; the aorta, which is highly elastic, if not likewise muscular, by reiterated divisions transmits it through every part of the system. From these parts the aortal branches, when they are reflected with a change of diameter, appearance, and struc- ture, become veins ; these veins, by reiterated unions, terminate at last in two large trunks, which are named cava ; the cavre discharge their blood ?nto the right or pulmonic sinus ; that sipus, by GENERAL OBSERVATIONS. 231 'muscular contraction, sends it towards the pulmo- nic ventricle ; that ventricle, having a greater mus- cular power, throws it into the pulmonic artery; and that artery, by its numerous branches, disperses it through the lungs, to undergo the change that is necessary from the action of the air ; after whicli it is received again by the veins, with which we be- gan, and conveyed again to the systemic sinus and ventricle, to be distributed as before to the sys- tem at large. From this account it evidently follows, that one set of veins in the human body, and in all animals that are similarly constructed, collects the whole cf the blood from the lungs to be transmitted through a heart and an artery to the system at large; that another set is made to collect it from the system at large, to be transmitted through a heart and an ar- tery into the lungs : Or, in other words, that one set of veins, together with a sinus, a ventricle, and an artery belongs to the system; and another, with a sinus, a ventricle, and an artery, to the lungs as an organ of respiration. The first set of veins, with the other parts connected in function, and conveying blood of a florid red colour, is here distin- guished by the epithet systemic ; the second, and the organs connected with it, containing blood of a dark purple colour, by the epithet pulmonic. The -distinction is made rather to point out their func- tion than position ; and the reason of this will soon be apparent. Both systems have their hearts enclosed in the same capsule, and the two hearts 23*2 GENERAL OBSERVATIONS. 'are so closely connected that we might suppose the two to be one, were it not for the septum that appears on dissection. The pulmonic sys- tem has all its arteries, and the systemic all its veins, ramified on the lungs ; and as the systemic has its arteries every where, so has the pulmo- nic system its veins. In short, wherever we see the arteries of one system, we see the veins of the other accompanying them; and 'vice versa. Hence the distinction as to situation being im- possible, it occurred to anatomists to distinguish them, by their functions, into that, which from the system carries the sanguineous fluid pulmonad, or towards the lungs ; and that, which from the lungs carries it systemad, or towards the system *. All veins have either a course peculiar to them- selves, or are seen to follow the course of the ar- teries ; those which observe a course of their own are generally superficial; those which follow the course of the arteries, generally deep, and are known by the name of vena satellites ; two venae satellites usually accompany each of the larger branches of arteries in the atlantal and sacral ex- tremities. All veins of the human body that are ramified on organs subjected to varied and extensive mo- tions, and particularly motions of the voluntary kind, are furnished with valves ; and hence in amputations of the atlantal and sacral extremities Vide Anatomic Generate, par Fra. Xavicr Bichat. OBSERVATIONS* ligatures around the veins are unnecessary; as valvular veins, when divided across, require a li- gature only at the orifice w,hich points towards the heart. In all veins, except the vena port arum hepatic a, the blood flows from the branches to the trunk, or from vessels of a less to vessels possessing a larger diame- ter, contrary to what takes place in the arteries. In such vessels, where there is no cause of ob- struction, the blood, from meeting with a less re- sistance than it does in the arteries, has less occa- sion for a vis a tergo, like that communicated by the impulse of a heart. The heart, however, may be supposed to assist the motion Jof the venous blood ; as the force which throws an injection into the arteries will often make it return by the veins. But another cause besides the heart, the pulsation of the arteries, and the elasticity of the veins themselves, is the action of the organs on which the venous branches commence, and along which they afterwards run. This action, while it retards the blood in the arteries, will generally promote its circulation in the veins ; and in those cases where this action is constant and uniform, and the organs through which the veins have to pass, are not subjected to changes of form, or to great varieties and extent of motion, it will, with- out the assistance of valves, enable the veins to propel the blood from the trunk to its branches, as in the vena port arum hepatic a. "'234 GENERAL OBSERVATIONS. The motion of the blood in the venae satellites is particularly promoted by the pulsation of those arteries with which they are in contact ; and the motion of the blood in the subcutaneous or super- ficial veins, by the elasticity of the integuments. These two sets, which have frequent communica- tions, are well calculated to assist one another: for when the muscles are thrown into action, the blood may flow, and actually flows, in greater quantity into those veins which are subcutaneous ; and when the integuments are contracted or com- pressed, it flows in greater quantity into the satel- lites*. Their mutual aid, however, is not neces- * As there are few who have not observed the swelling of the subcutaneous veins on the back of the hand when warmed at a fire, and who have not noticed their gradual enlarge- ment upon the face, and over the distal parts of the extremi- ties, when the integuments are flaccid through age, it is not surprising that the application of cold and of bandages, when skilfully managed, should have been found so generally use- ful in cases of disease where the distension of these veins had either produced, or threatened to produce, that unseemly ap- pearance which is termed vaructf. If such remedies were re- sorted to in time, they might often save the trouble of that operation, where the trunk of the varicose vessels is laid barr, and after being cut is tied with a ligature at the orifice point- ing towards the heart, the only ligature, as already observed, that in general is necessary ; for should a branch open near the orifice that points dktad, and on the distal aspect of the valve, the retrocession of the venous trunk, with the consequences that follow, will in most cases prevent any hemorrhage. GENERAL OBSERVATIONS. 235 sary merely in the voluntary actions of the mus- ,cles, or when the integuments are contracted by cold ; it seems to be necessary in a great variety of mental emotions, in various diseases, and in modes of respiration ; for in many of these we see often the blood hastening to the surface, and in many retiring from it as suddenly. There is some peculiarity of circulation within the cranium. The dura mater and the pia mater are not supplied with the same branches. As the one is stationary and the other moveable, the de- licate functions of the cerebral substance might Hot permit the chance of interruption in the cir- culation of the veins or the arteries as they pass between the membranes. The veins, however, of the cerebral substance, and which are ramified on the pia mater, convey the whole of their blood from the centre towards the circumference ; and although they collect none of their blood from the dura mater, they discharge their contents into its sinuses. They are assisted in performing their functions by the general resistance made by the .cranium, by the combined pulsation of the arte- ries, and by those motions of the cerebral sub- stance that are the consequences of respiration. From the sinuses occupying various situations, glabellar, coronal, inial, and basilar, and extend- ing basilad towards the dextral and sinistral as- pects, and where they are basilar, extending late- rally dextrad and sinistrad, the veins, by entering 236 GENERAL OBSERVATIONS* those which are nearest, run comparatively but a short course ; and then when their blood is lodged in these sinuses, it can neither accumulate to in- jure the brain, by occupying more than its own space, nor have any chance of rupturing its ca- nals, either from its quantity, or the more than or- dinary agitations of the head. In the eye, the brain, and other situations where the veins and the arteries are seen to observe dif- ferent courses, it must be obvious that the parts around them may be differently affected at the same time ; that the blood may be accelerated in one set of vessels, while it is proportionally retard- ed in the other ; and that the circulation may in this way be varied, not only to suit the operations of the organs, but to accommodate these ope- rations more readily to volitions, emotions, and passions, and the other causes that affect the cir- culation, as it is often seen in the voluntary or- gans, from the two sets of veins. A different reason must be assigned for that peculiarity of the venous circulation which has been remarked by every anatomist in the cavity of the thorax. The cava inferior, which returns the blood from the sacral extremities and from the abdomen, has no course to run in the thorax. On receding from the bodies of the lumbar ver- tebrae, and receiving the blood that circulates in the liver, it immediately afterwards perforates the diaphragm ; and no sooner perforates than it CENERAL OBSERVATIONS. also terminates, discharging its contents into the right or pulmonic sinus. From this circumstance the inferior venous intercostal vessels cannot send their blood to it, without taking a circuitous course, passing through the diaphragm, entering the ab- domen, and exposing their action to many inter- ruptions. Nay, even were the cava continued in the thorax, as we commonly see it in the lower animals, yet still the intercostals could not enter it with safety, on account of its distance from the bo- dies of the vertebrae, and the want of support in the intervening space. For these reasons, the in- ferior intercostals run mesiad, following, however, the curvatures of the sides, and enter a vein, call- ed the ^ena azygos, resting on the vertebras, and si- tuated on the right side of the aorta. This vein, as it passes along, receives the blood from all the .inferior intercostal veins (not unfrequently from some of the lumbar, where the cava inferior re* cedes from the vertebra) ; and proceeding atlan- tad as far as the third of the costal vertebrae, ad- vances sternad, sinistrad, and sacrad, and, form- ing a curve, discharges itself into the vena cava superior, where its blood mingles with that from the head, the neck, and atlantal extremities, and from the thoracic, the superior intercostal, and th$ two internal mammary veins. This vena azygos, which receives the blood from the intercostals, being situated on the dextral side of the aorta, where it lies in the thorax, for 6 238 GENERAL OBSERVATIONS* the same reason that the cava inferior is situated on the dextral side of the aorta, where it lies in the abdomen, that it may be near the pulmonic ventricle, many veins on the left, in their trans- verse passage, must cross the arteries either on the dorsal or the sternal aspect, and have their circu- lation occasionally interrupted, or at least more impeded, than the corresponding veins on the right. To this circumstance Morgagni has as- cribed the greater frequency of disease in the left than the right kidney*, and appears strongly inclined to believe that a similar difference will also be found between the left and the right ova- riumf. If the cause which he has supposed be the true one, it should also follow that the left side, in the region of the thorax, should be more liable to dis- ease than the right, as its venous intercostals have to pass dextrad, between the aorta and bodies of the vertebrae, to the vena azygos. Now the questions will be, Is the left side more liable to disease? Have any observations been made upon the subject ? and, Do these observations countenance the hy- pothesis? On a cursory view of the Letters of Morgagni De Sedibus Morborum, I found, that of eighteen females that had been affected on one side, there were only four affected on the right ; * Epist. XL. 13. f Epist. XXXIX. 5 40. De Sedlbus Morborum. 4 GENERAL OBSERVATIONS* but that of males an equal number, or rather a greater ^ were affected on the right. The cases of the females corroborate the hypothesis, while those of the males seem to overturn it, if we are not to suppose, with respect to the males, that the right hand being more frequently employed than the left, its habitual, vigorous, and extensive ex- ertions were greater disadvantages to the right side than the unfavourable courses of the veins, were to the left. Much has been said of the difference of func- tion observed between the right and the left sides ^ and much has been ascribed to the difference of manner in which the carotid and subclavian arte- ries, on the two sides, arise from the aorta. But let it be considered, that if the subclavian and ca- rotid artery of the right side did not originate from a common trunk, the subclavian must have risen at the very commencement of the aorta, and its orifice, far from the bend of the arch, been unfa- vourably situated for receiving the blood ; or the arch of the aorta, as sometimes happens when these two branches arise separately, must have been, somewhat different in form, and extended more widely from right to left, to furnish space for the Separate origins. To such a difference with re- gard to. structure, we can therefore ascribe but ve- ry little difference as to the functions. The appa- rent variety seems rather calculated to preserve a similarity, than occasion a distinction, as to effect between the two sides. GENERAL OBSERVATIONS, The other differences are far from being so ea- sily explained. The eight pair of nerves, as well as the arteries, regularly exhibit different appear- ances on the right and left, and particularly with respect to those branches that are called recurrent; the one on the right being reflected around the right subclavian artery, and the one on the left around the aorta. The great trunk, too, of the absor- bents, from following the aorta, and avoiding the oesophagus, terminates in the veins of the left side ; and at the angle where this trunk enters, the left subclavian and internal jugular form also a trunk that runs transversely on the sternal aspect of the carotids to the cava superior, and unlike to any venous distribution that is seen on the right : And yet what can we infer from all these differences, from the particular position of the heart, from the situations of the stomach or liver, or from the lungs of the right side having one lobe more than the lungs of the left ? Certainly very little. For notwithstanding this difference of structure, the difference of function is not very obvious. Many operations, it must be confessed, are better per- formed by one hand than by two; and whether the one or the other be employed, will depend very much upon choice. Both hands frequently cooperate, and in many cases both are equally- fitted to perform every part of the common la- bour. If there be cases where the labour is divi- ded in such a manner that each performs, and OBSERVATION^ 941 can only perform, a particular part, may not this division, in most instances, be traced to fashion and to previous habit? and is it not likewise in consequence of fashion, that when any individual happens to deviate from the usual practice in as^ signing to his hands their share and proportion of any operation, we are induced to call him left- handed? while the left-handed, to avoid the re- proach w r hich fashion attaches to what she consi- ders as inattention, vulgarity, or awkwardness, sometimes pretends to be ambidexter ; a pretence that has often a ludicrous effect when brought to the test of actual experiment, for who has seen any that, strictly speaking, can he called ambidexter ? I believe none* To do a thing well, and parti- cularly any thing that requires much study and, practice, the hand that performs it, be it right or left, must be trained for the purpose. The influence of habits, the undefined capabili- ty of the organs, the numerous resources of the vi- tal principle, and the power which it has of ac- commodating the system, and parts of the system, to various operations and to various circumstances^ are things with which we are but little acquainted ; and ignorance here, if attended with presumption, must frequently lead to hasty experiments and to hasty conclusions, in deciding upon ivhat are cau- ses and effects in the animal ceconomy. If we carl hardly therefore deny, we can hardly with an)7 confidence assert, that the differences which we see GENERAL OBSERVATIONS. between the structure of the two sides are the cau- ses of the preference which is generally given to the right hand over the left. That the arterial and venous systems exhibit varieties of ramification, is easily demonstrated, and that these varieties are each of them suited to the nature and functions of the several organs to which they are destined, is probable from almost every observation. We see that amidst the number of changes which take place at birth, the nature of the whole circulation is alter- ed ; the umbilical arteries and vein, the ductus veno- sus and ductus arteriosus, gradually obliterated, and other vessels as gradually enlarged. We daily see changes in the size, the anastomoses, and the ramifi- cations of the smaller branches ; and we see these changes attendant on tumours, on inflammation, and on the varying states of the organs. We see the changes of ramification in the atlantal and sacral' extremities proportioned somewhat to the varieties of voluntary motions, and are led to expect them fewer in number where the motions are regular and 'ess extensive. At the same time, a difference of structure in any of the organs does not always imply a difference in the ramification of its vessels. The same vessels, without any change as to structure or appearance, may be capable of great varieties of action ; under the influence of emotion or passion, they can alter the qualities of the blood in a mo- ment, as we learn from several experiments of Hewson ; and in cases of injury, we see not only their action accommodated, but new vessels some- GENERAL OBSERVATIONS. times produced, the old ones repaired, and some- times obliterated, as best suits the object, which We know from experience to be the object in view. In short, no subordinate part of the structure, the nervous system only excepted, seems more imme- diately under the influence of the vital energy than the 3anguiferous ; and considering its won- derful effects on the blood, it should not by any means appear surprising, if some, from a cursory View of the phenomena, should have imagined that Vhere was a sort of life in that fluid. THE ABSORBENTS. MANY of the smaller branches of arteries, which are not reflected to form veins, are known to ter- minate on the surface of the skin, on the surface of the several internal cavities, in the excretory ducts of different glands, and in the various organs of the system. The fluids which they discharge on the surface into excretory ducts, or into cavi- ties that have ducts or passages opening peripherad, are either expelled, or may be expelled, entirely from the system ; but the fluids which they depo- site in organs, that part may be assimilated in growth and nutrition, and the fluids discharged into shut cavities, to lubricate the parts, to facilitate motion, and prevent adhesion, must, if they flow in regular succession, be either accumulated, or returned tot the heart by veins, or by some other system of ves* ^44 GENERAL OBSERVATIONS* sels. They are known to be returned by u- set &S vessels that are named absorbents. The absorbent vessels are generally found lying by the sides of the veins and the arteries, bu* so very small, that the diameter of the common trunk, in which most of them terminate, is seldom larger in a healthy person than that of a crow quill. They all terminate ultimately in the veins that are called pulmonic. In most animals they all, like the veins belonging to the head, neck, and extremities, are very plentifully furnished with valves ; and they all, like the veins, convey their fluid, in the first instance, from branches to trunks.: or, should any of them happen to pass through glands, like the vena portarum^ they transmit it alternately from branches to trunks, and from trunks to branches. In other respects they differ considerably. With regard to number, the density, thinness, and trans* parency of their coats, they exceed the veins as- much as the veins are usually known to exceed the arteries. They may be divicled into different sets accord- ing to their offices and their commencement* Those commencing from shut cavities, from arteri- al branches, or the substance of organs, may be considered as accessory veins, conveying back a part of the fluids that had been sent from the heart by the arteries. But as the fluids sent by the ar- teries are sometimes assimilated and become solid, sometimes undergo morbid changes, arid some- times, When assimilated, separate again and be- GENERAL OBSERVATIONS. 245 come fluid, these absorbents are also employed toTeturn whatever is morbid or decayed, that it may mingle again with the blood, be made to un- dergo new preparations,. or be thrown entirely -out of the system. In ^his class, the existence of those wfoich are >aid to commence from arterial branches -has been called in question : But as Mr Cmickshanks -seems to have proved it both by experiment and observa- tion, the business is now, to ascertain, if passible, their uses ; and though this be a task which we cannot presume to execute with great minuteness or accuracy, we -are certainly entitled to draw the conclusion, that by such vessels the quantity of thin and transparent fluid -that flows in the brarv ches of arteries or veins, or that is -deposited on surfaces or in organs, may be variously regulated. The other sets are those which commence from the surface without, and the alimentary canal with- in. All living bodies, in their -earliest state, are nourished by absorbents commencing from the sur- face, or from organs beyond it; the vegetable tribes, through the whole of their lives : but the animal tribes, as soon as they begin to receive food, in con- sequence of their own voluntary exertions, by ab- sorbents also, commencing from an alimentary ca- nal. This canal, by no means intended as a mere repository of nutritive stores, nor to save the trou- ble of constant exertion in procuring the neces- sary supplies of nourishment, is differently co.i* 4 OBSERVATIONS. structed in different animals ; and, according to th# species, is provided with different instruments and juices to prepare the food, to adapt it to the system, and to render it fit for entering the absorbents. From the qualities of our fluids depending so much on its previous operations, we are led to con- ceive how the general health is so much regulated by the stomach and intestines; and in some mea- sure are able to explain how medicines, directed to a part of the system which exercises so general an influence over the whole, should, if skilfully employed, prove singularly useful in various dis- eases, and should, from the parts to which they are applied being more within our reach than any other part, excepting the surface, have also their ef- fects better ascertained, and be under more obvi- ous and accurate management than medicines of almost any other description *, The absorbents commencing from the surface of the body may, at all the different periods of life, be easily demonstrated in the genus Rana, as the individuals belonging to that genus may be show 7 n to increase in bulk and in weight when aqueous, fluids are applied to their skin. In man, indeed, and in many other animals, absorbents commen- cing in that situation to convey nourishment, or to supply the place of respiration, become less ne- * For the singular effects of medicines directed to this part of the system under skilful management, sec Hamilton's Ob- servations on Purgative Medicines, 6ENERAL OBSERVATIONS. cessary, as their respiration cannot be suspended, and as their nourishment is principally, or almost wholly, conveyed by absorbents commencing from the central surface of the alimentary canal. On these accounts, the effects of absorbents commen- cing peripherad, being neither conspicuous, nor perhaps very regular, in the human body, some physiologists have lately begun to deny their exist- ence ; and to deny it because the fluids, in some of their experiments, when applied to the skin, were not sensibly absorbed. Without question- ing the certainty of the facts, or. doubting the vera- city with which they are narrated, it may safely be said that the conclusion 'has been hastily drawn. In these experiments it was taken for granted, that all liquids, if equally fluid, and if not obvi- ously injurious to the system, would, at all times and in all circumstances, be readily absorbed, pro- vided absorbents opened from without. These are postulates that cannot be admitted : Much may depend on the state of the fluid, as being a liquid, a gas, or a vapour ; much also on the properties of the fluid in these different states ; much on the state of the system and integuments, tmd the state of the absorbents at the time of the experiment. All agree that the scarf-skin is po- rous, and that it is perforated by exhaling vessels ; all agree that absorbents commence immediately beneath it ; and all agree, whether they happen to commence or not from its peripheral or outward surface, that mercury, by a little pressure or friction, 248 CENERAL OBSERVATIONS. tnay be made to enter them. Nor let us infer from the pressure and friction, that the scarf-skin is destroyed; we can here appeal to the evidence of sense, which demonstrates the contrary. The absorbents at times are certainly, not more than the veins and the arteries, totally independent of me- chanical aid. From the greater degree of resist- ance that is made by the bones of the cranium and the vertebral tube, we can see the reason why the Spina bifida never takes place but in very young children, and why the Hydrocephalus inter^ nus occurs less frequently in adult persons than in those where the sutures of the cranium are open, or the head is expanding in consequence of growth. We may also see how, from the want of mechani- cal aid, the water is ofteri apt to be accumulated ifi the sacral extremities, where the integuments are much relaxed, the motions languid, the posi- tion erect, and the system debilitated; and how this- absorption is afterwards promoted by the pressure of bandages, the change of posture, and the resto- ration of the skin and the muscles to their healthy functions. THE NERVES, EVERY nerve that has yet been discovered in an animal body regularly formed, has proceeded di-r rectly or indirectly from a cerebrum^ a cerebellum, a medulla oblongata, or medulla spinalis : the two for- mer are what principally constitute the brain. They may eaci* be divided, and are partly divided* dENERAL OBSERVATIONS. 249 into similar halves towards right and left ; each of the halves sends forth a pedicle, pedunculus, or crus; these pedunculi or crura afterwards unite, and form what is called the tuber annulare : from the tuber annulare to the foramen magnum of the oc- ciput, with a change of form, they take the name of medulla oblongata ; and this medulla, after enter- ing the vertebrae, is, almost without any change of appearance, called medulla spinalis. The medulla spinalis, as remarked by Soemmering, bears a greater proportion to the contents of the cranium in the lower animals than it does in man ; and for this reason, that as we descend in the scale of be- ing, the brain is observed to grow proportionally smaller and smaller. In amphibia, and a great number of fishes, the diameter of its cavity be- comes so small as scarcely to exceed even the dia- meter of the vertebral tube. In the tribe of insects it entirely disappears, leaving only a spinal mar- row and nerves ; and even a spinal marrow and nerves are sought for in vain in the families of plants. The laws by which these phenomena are regu- lated may partly be traced. The nerves distribu- ted to the organs of sense and voluntary motion are, compared to the parts on which they are ramified, proportionally the largest in the whole system. The radial, the ulnar, or the median nerves, are larger than the middle or great sym- pathetics, that supply the viscera of the thorax CFNERAJ, OBSERVATIONS. and abdomen; and the digital branches, at the points of the lingers, are larger than those whicb. are seen entering the basis of the heart. In those parts which are naturally insensible, the vestige qf a nerve is never to be seen; nor would ever the existence of a nerve be suspected, unless from oc- casional degrees of sensibility when the parts are morbid. Even in the parts which are naturally sensible, but not organs of sense or voluntary mo- tion, we should hardly be able to trace any nerves, if we were not previously acquainted with the trunks from which they are derived; and should hardly be able to decide on the nature of the trunks themselves, if we did. not trace them to others that are larger, and these to the brain or the spinal marrow. Reasoning, therefore, upon the principles of general analogy, we need not be surprised thai a nervous system, supposing a nervous system iu plants, should escape even the most penetrating sight, when searching for it in those organic bo- dies that are destitute of brain,, of spinal marrow, of sense, sensation, and voluntary motion. All nerves have been divided into those which are sensible or insensible, voluntary or involun- tary : the sensible being those which obviously and suddenly communicate intelligence to the vi- tal principle, of the injuries or changes that take place in the system, or of the impressions that are made from without; the insensible, those which perform their operations obscurely and secretely,. OBSERVATIONS! to the senses, and without in general awakening our consciousness ; the voluntary, those which are either subservient, or at least partly subservient, to the will ; the involuntary, those, the functions of which are obvious to the senses, but on which the will has no direct or im- mediate influence. This division, although it be useful on certain occasions, is far from accurate. On looking for marked and permanent charac- ters by which these kinds of nerves are distin- guished, WQ perceive none. The distinctions are made to rest entirely on modes of action, on cer- tain partial differences of function, and on par- tial differences that are liable to change. The sensible nerves grow ofien insensible, and the voluntary nerves often involuntary, in conse- quence of palsy ; while insensible nerves, on the other hand, are often observed to become sensible from the diseased state of the parts on which they are ramified. Voluntary nerves, though generally sensible, do -not appear to be necessarily so. There are volun- tary nerves w r hich are either insensible, or next to insensible, in some insects. When a gadfly has once fixed on the hand and tasted of the blood, its wings, its legs, its antennas, and even abdomen, may be amputated without interrupting, or at least apparently, the pleasure which it seems to derive from the suction. Involuntary nerves, although exempted from any direct influence of the will, are seldom ex- GENERAL empted from the effects of fear, of anger, or afiy tus, and temperature of the blood ; to the laxness and density of the cellular membrane ; to the ra- mifications of the nerves themselves ; to the cour- ses which they take ; to their plexuses and gang- lions ; and also to the parts from which they ori- ginate. With these circumstances, we know in gene- ral, from repeated observation, that the functions of the nerves are somehow connected ; although^ as to that variety of function which belongs ex- clusively to each of the circumstances, we know very little : it being at all times difficult to say how much depesods on the nature of the organs, how much on the agent that employs them as instruments, how much on the stimulants that prompt its exertions; the principal phenomena, in all living bodies, being generally the effects of a great number of causes combined causes, too, whose actions are modified by the very effects to which they give origin ; effects that in their turn operate as causes, and on many occasions produce effects similar to the causes that produced them-* selves. As an intimate acquaintance with all the cir- cumstances immediate and remote, on which a function, or the modification of a function, de- pends, is a knowledge to which we never can as- pire ; and as the light by which we are guided is. a light in which distant and minute objects sel- dom appear, we must limit our desires to partial GENERAL OBSERVATIONS* glimpses, and must rest satisfied when these be obtained. As great differences in the general appearance of the nervous system are always accompanied with very obvious differences of function in the several classes and orders of animals, we shall only suppose that the smaller differences have pro* portional effects, though we cannot so easily or clearly demonstrate them. On inquiring into some of these smaller differences, we think we can see a difference of function arising from the course of the nervous branches that are called re- currents. These branches, proceeding from the trunks of the eighth pair, par vagum, or middle sympathetic, enter the thorax, transmit some ra- muli to the cardiac plexus, and then, returning each round an artery, are ramified on the la- rynx, which they formerly had passed in their pro- gress sacrad. In consequence of this singular course, when the action of the heart or arteries is changed, we generally find that a part of the change is indicated by the voice. We see the nerves not immediately subjected to the influence of the will distinguished, not only by a proportionally smaller size, but likewise by certain swellings or knots that are named gang* lions ; and as all these nerves are subservient to functions that are constant and uniform, it has been supposed that their ganglions are both reser- GENERAL OBSERVATIONS. and sources of the nervous energy ; and that fcy affording a regular supply, and resisting those occasional commotions excited by volition, they are calculated to preserve that uniformity in point of function by which .the involuntary nerves are distinguished. The friends of this hypothesis, although they must allow that it is certainly far from demon- strable, may however maintain that it is support- ed by the phenomena of the nervous system that appears in insects. In these small animals^ a nervous cord, that sometimes divides, some- times unites, and always exhibits a number of ganglions, is observed to extend from the atlantal to the sacral extremity. The ganglions which it forms are the parts which principally send out the nerves : they send them out to parts in their vici- nity ; and these parts, from having derived their nervous energy chiefly from the ganglion, are ob- served, when separated from the rest of the sys- tem, to retain their independence as to irritability a considerable time ; while the parts that remain equally independent, or more so, by their union, are but slowly affected, comparatively speaking, by the partial loss. The principal objection to the hypothesis is what arises from some of the functions observable in the organs that are destined to perform volun- tary motions. In these, as in all the organs of the body, there is a number of vital processes GENERAL OBSERVATIONS. larly going on, independent of volition; and hence circulation, nutrition, absorption, continue in a muscle after it is deeply affected by paralysis. From this it must follow, that these kinds of func- tions are either performed without the assistance of any nerves belonging to the muscle; or that if nerves be actually concerned, they must terminate "differently, have a different origin, or be some- where in their course modified differently, from those which are voluntary. The answer which is given by those inclined to favour the hypo- thesis is, that the assistance of the nerves is ne- cessary ; but that there may be filaments in the same branch that differ as to origin, termination, and size, and as to changes that take place in their course : that the smallest branches which we can see with the naked eye appear through the microscope composed of fibres : that when these branches are traced to their trunks, and the trunks again to the spinal marrow, they are found to be partially connected with ganglions : that the spi- nal marrow, composed of the four crura of the brain, emits four rows of nervous filaments, two of them dextrad, and two of them sinistrad; one of the two issuing from a sternal, the other from a dorsal cms of the medulla; both of them collect- ed into small fasciculi; and two fasciculi, a dorsal and a sternal, of which the dorsal has always a ganglion uniting to form each of the nerves that pass through the intervertebral foramina ; that, GENERAL OBSERVATIONS, besides, if the crura be followed atlantad, they will lead to the ganglion called tuber annulare^ where probably a considerable portion of the cru- ra undergoes a change, that partly may contribute to modify the functions. of those nerves that after- wards proceed from them : that all nerves, from the fifth pair inclusively, issue fro?n the crura af- ter the tuber annulare is formed : that each half of the first pair of nerves swells into a ganglion before it perforates the ethmoidal bone : that the halves of the second are observed to unite in the sella tutcica, where they seem mutually to assist one another : that the third pair rises close by the edge of the tuber ; the fourth, from the two of the corpora quadrigernina that are situated basilad : and that all the nerves in the human body are di- rectly or indirectly, wholly or partially, connected either with ganglions or plexuses, or with both. The use of the plexuses* is less obscure than that of the ganglions, and their appearance as different from the gangliform as the retiform tex- ture of the absorbents is from their glandular-like convolutions. In the large plexuses forme$ by the nerves of the atlantal and sacral extremities, we see a number of communicating branches pass- * I have added here an English termination to the word plexus ; as the singular and plural of that word can only be distin.* guished by the meaning of the sentence in a language such as ours, where the adjectives arc never, and where even the verb* are but sparingly inflected. R OBSERVATIONS. ing between one trunk and another, and which, like the inosculating branches of blood vessels, contribute to secure a more regular supply of that sort of energy which nerves convey to the diffe- rent parts on which they are ramified. Such communications might naturally have been ex- pected in all the other parts of the system ; and accordingly we find that all the other nerves is- suing from the spine, and severals from the head, although they be not mentioned as forming plex- uses (which are merely connections of certain ap- pearances), are nevertheless, near to their origin, connected directly or indirectly with the nerves in their vicinity, and frequently w r ith others near their distal extremity, where they terminate in famuli, or smaller branches. In some cases the plexuses appear, as well as the ganglions, to be formed by the parts of the same nerve ; in all cases the plexuses, too, as well as the ganglions, when not the effects of more inti- mate unions, are somehow preparatory to wider separations ; in a few cases the appearances of both are closely intermixed ; and in many cases they probably exist where the anatomist cannot easily discover them ; as among the slender fila- ments of nerves, where these are concealed in a common sheath, or at the commencement of the -nervous cords in the spinal marrow, medulla ob- longata, or tuber annulare. Physiologists at least are accustomed to trace particular connections among the organs that, distant or near, derive their G1NIRAL OBSERVATIONS. 250 nerves, not merely from the same ganglions or plexuses, but the same trunks, or the contiguous corresponding parts of the brain and its crura. It is thus they explain the sympathy between the eyes and the nose, when a strong light impir^es on the one, or a pungent odour is applied to mt other ; that between the liver, at the coronary li- gament, and the right shoulder ; that between the diaphragm, at the pit of the stomach, and the muscles of the neck, in cases of tetanus; and, lastly, amidst a variety of others, that strong, mark- ed, and general sympathy between the similar halves of the system. This last sympathy cer- tainly implies something more than a mere similarity and contiguity of the respective nerves at their commencement; for, in reasoning from analogy, on looking back to the ganglions and plexuses, to the bones divided by the mesial plane, and to the trunks of the veins and arte- ries, with their branches ramified towards right and left, it seems also to imply a mutual, though partial, interchange of substance between the dex- tral and sinistral portions of the brain and its crura a notion corroborated by decussating fibres that have been observed in the medulla oblongata, and by those not uncommon cases of palsy, where the brain and the trunk, so far as regards the volun- tary functions, are known to be affected on the contrary sides. If sympathies occur which cannot be explained GENERAL OBSERVATION 3, by these relations existing among nerves; it is net because these relations are useless, but because there are other sources of relation to be found in the system. Distant parts are related by absor- bents, blood vessels, muscles; by a like sensibility with respect to stimulants; and by being concern- ed in different parts of the same common func- tion, as the skin, the lungs, the kidneys, and in- testines, in discharging the noxious or superfluous fluids ; or distant muscles when they co-operate in some general movement or attitude. Besides, the great source of connection, and to which all the rest are subordinate, is that principle which regu- lates and presides, to which every impression is directed, and from which every vital action pro- ceeds a principle that makes every organ in the body to act and to sympathise with the whole, and the whole with every organ when necessary. Of the parts composing the brain, or the ence- phaUn, we may say in general, that, as well as the nerves, they are certainly organs of the vital prin- ciple ; though, as to the kinds of particular func- tions in which it employs them, we be totally ig- norant. What is more humbling, we can even say nothing precise and satisfactory of the general functions that distinguish the cerebrum and cere- bellum. From the numerous varieties, indeed, that occur in the cerebra of different species of animals, and the few, comparatively, that are to ba seen in their cerebella, we perhaps may venture on this GXNERAX OBSERVATIONS. 26l general con elusion, that the cerebellum is employed in functions that are common to various species of animals, and .the cerebrum in the functions by which they are distinguished, as in those which regulate the differences of form, structure, arrange- ment; the differences of passion, .appetite, and in- stinct. As for much more precise and particu- lar conclusions, we have hardly any data on which .we can proceed with confidence or safety; our anodern craniological theories, like the fabulous tales of unknown countries, being calculated rather $0 amuse than instruct,. "LiFE AND IRRITABILITY. 'Tnz differences of function arising in the organs from a difference of substance and a difference of structure ; from a difference in the veins, arteries, absorbents, and circulating fluids; from a differ- ence in the cellular membrane and nerves, and a consequent difference of the vital influence contribute to occasion those irritabilities which Harvey has denominated the sensus proprii. These sensus proprii, by a modern discovery, have been ascribed to vit& propria. The vita propriae are the functions personified; and though somewhat different, are yet somewhat akin to the vis gcni- trix t the vis concoctrix, the vis medicatrix, and the other vires of the old physiologists, who seem to have derived them from the Greek 4 262 GENERAL OBSERVATIONS. mentioned by Hippocrates, and which were the ministers of Physis or Nature. They succeeded in office to the ancient Genii, that at one time had presided in the organs, and that had been accus- tomed, when they happened to meet with judicial astrologers, to regulate their conduct by the influ- ence of the stars. As the modern vitse have all been reduced by the celebrated Bichat to two kinds, the animal and organic, the former distinguished chiefly from the latter by the functions, sensation, and voluntary motion; so the ancient Awa^e/c, the ministers of Physis, were classed by Plato under three souls, the rational, animal, and vegetative ; a classification that, with little or no material alteration, was adopted by Galen, and by most of his followers. With a little more patience they might all have been traced to a common source ; for the truth seems to be, that all these functions, vita, faculties, vires, dynamics, or whatever be their names, ori- ginate principally from one cause, operating va- riously by various organs, and often itself operated upon by various causes, that in many cases, from the appearances of design and intelligence, seem to be under either the mediate or immediate di- rection- of the Author of nature. As for the hypothesis that admits the existence of vital laws and vital phenomena without the ex- istence of a vital principle, it is scarcely intelligi- ble. Laws, strictly speaking, are but forms by OBSERVATIONS. 263 wiiich something is regulated : but as here there is nothing found in the hypothesis which appears to regulate these vital laws, and nothing vital to be regulated by them, with a strange inconsist- ency these laws are considered as animated be- ings putting their own regulations in force. In this character it is hard to perceive any difference between them and the old personified vires or dy- namics. In short, the supporters of this opinion, instead of succeeding in their attempts to exclude entirely a vital principle, have inadvertently ad- mitted a number ; and instead of advancing any thing new, as they probably supposed, have cer- tainly revived one of the most rude and antiqua- ted notions in all physiology, though strangely dis- figured by the difference of language in which it is expressed. As the vital principle is acknowledged to possess but limited powers ; as the exercise of its powers is also limited by the nature of the organs, and the exercise of the organs by varieties of circumstances; as the organs themselves are all composed of the particles of food, and these particles but partially subjected to the vital influence we can hardly imagine that such a principle would ever be able either to construct or preserve its system totally in- dependent of external causes. To maintain, there- fore, a regular intercourse with external causes, that may serve it as auxiliaries, and to avoid or repel those that are inimical to its operations, S64 GENERAL OBSERVATIONS, all its organs are found to be endowed with that kind or degree of irritability by which they are each peculiarly suited to their respective offices, and to the .stimulants intended to act upon them. These irritabilities, which are modified by the state and nature of the organs, seem partly to de- pend on -the regular exercise of the vital powers, and partly on the kinds of external causes that co-operate as auxiliaries : They depend chiefly on the vital influence in all living bodies that are found to possess a heart and a brain ; the heart by means of an artery and its branches, and the brain by means of its crura and nerves, diffusing this in- fluence through every organ that is near or remote : They depend less on this kind of influence where the size of the brain, or the brain and the force of the heart, are but small ; as in all those animals where the temperature is low, and the circulation comparatively languid : They depend still Jess on this kind of influence where a heart and a brain appear to be wanting, and the duty is left merely to an artery, a spinal marrow, and their respective branches : Least of all on this kind of influence where nerves and arteries vanish from the sight, and where all nourishment is conveyed by absor- bents opening from the surface ; by an inverse ra- tio, in all these cases they depend on external or auxiliary causes. As for their continuance after the causes have ceased to operate, that must be inversely as the GENERAL OBSERVATIONS.' .constancy and extent of their dependency on the Operations by which they were supported, or di- rectly as the permanency of the general conse^ quences of these operations ; and as for their con- tinuance in a separated organ, that must be in- versely as the constancy and extent of their depen- dency on the vital principle and those auxiliaries that have ceased to operate, and directly as the in- fluence of those auxiliaries that continue to ope* rate. Separated organs, when they have retained their irritability a considerable time, have sometimes again been united to the system, sometimes to the part from which they were taken, sometimes even to a different part, and sometimes even to a dif- ferent system, where the parts were congenial. In a Latin thesis, entitled De Anima, sen Principio Vitali, which I published at Edinburgh in 17Q6, 1 had hastily concluded from these phenomena, and from some others that are usually exhibited by cer- tain species of polypi and plants, that the vital principle itself was divided : It now appears, on more considerate and extensive inquiry, that irrita- bility is never the direct or immediate operation of the vital principle, but only the consequence of its operation ; and in no case exclusively the consequence, but the consequence likewise of other operations proceeding from a number of different causes : and hence it is, that a vital principle may often exist where it cannot operate, in a sensible GENERAL OBSERVATIONS. manner, from the want of auxiliaries; and hence it is, likewise, that its effects may often be continued, at least for a while, after its departure. With regard to the portions of plants and polypi that continue to live in a separated /slate, assume the form of their respective species, and propagate their kind, they will be found, on a close exami- nation, to have been originally complete systems ; many of the plants, and many of the polypi, that are usually considered as simple individuals, not constituting one animated system, but rather a con- ?s of animated systems a congeries, too, which after all is nothing more than a species of society, where anm ated beings are associated together for mutual protection ; such as we see among men in a city, among bees in their cells, or among insects that construct habitations, which, in point of form, are similar to plants. From the irritability of the several organs, the functions are always partly regulated by external causes. It is therefore we see the instincts of ani- mals, and more than the outward appearance of plants, varying with the* change of season and cir- cumstance, that seem to exert an influence from without inversely as the influence of the vital prin- ciple, which operates from within. What here has particularly been matter of surprise is, that on all the organs of animals, the organs of sense not even ex- cepted, impressions should be made, and consicle- Table changes, local and general, induced on the GENERAL OBSERVATIONS. 2t)7 functions, long before there is the most distant in- timation or consciousness of what has taken place. The insensible changes made upon the organs would seem to be at first insensibly communicated to the vital principle, from the vital principle insensibly communicated back to the organs, till, gradually increasing by the continued and alternate recoil, strong emotions at last are excited, conscious- ness roused, and the voluntary powers brought in- to action, with a change of place, attitude, or con- duct, suited to the newly induced dispositions. It is thus we sec ends frequently obtained, and the interests of the animal and species promoted, in a way that indicates superior design, intelligence, and foresight ; but a design, intelligence, and foresight, in which the judgment and reflection of the animal never were concerned; and which, therefore, with Virgil, and with other studious ob- servers of nature, we must ascribe to the Sovereign of the universe, in whom we live, move, and have being. Other processes equally obscure, equally won- derful, and equally important, though more fami- liar from their daily occurrence in the animal sys* tern, appear to commence in the organs themselves; and, like the preceding, awaken consciousness on- ly at the periods when they happen to require the necessary aid of the voluntary powers in al- laying thirst, hunger, or desire ; in procuring sleep l26B -GENERAL OBSERVATIONS. or expelling from the .system what is useless ari# hurtful. Even plants themselves are so wonderfully re- gulated by external causes, that, in many instances, they seem to be no less wn forward, before we can assume the erect posture. In the changes of attitude, while a bone is turning on its centre of motion, the centre itself is often at the time describing either the seg- ment of a circle, or a line composed of the seg- ments of circles. Suppose AB represents the foot, BC the tibia, CD the femur, and DE the trunk, and that the three last are to be brought by the action of their GENERAL OBSERVATIONS. muscles to the perpendicular BF, so that BC shaJJ THF A NB occupy the situation of BG, CD the situation of GENERAL OBSERVATIONS. GI, and DE the situation of IF ; the point C on tha centre B will move in the segment CG, and as is changing its position in CG, the point D, which moves round the point G as its centre, will, if the extensions be regularly performed in the same time, describe such a curve as DI :: for, as the point D must necessarily move atlantad and sternad, in order to preserve the centre of gravity, the general direction of its course must be known; and if CG be divided into equal parts, and at each of the di- visions a circle described with the radius CD, the points in DI, corresponding in number with the points in CG, and at equal distances in the ster- nal direction, will each be found in the circumfe- rence of one of the circles described successively round the point C as it passes along the segment CG. In like manner, if the extensions of CD and DE be regularly performed in the same time, the point E will describe such a curve as EF, the points in EF being in the circumferences of the several circles successively described round the point D as it moves, along the curve DI. The figure is also calculated to show how the rapid extension of the several joints may carry the body directly upwards; the motions are alternately dorsad and sternad, and all of them atlantad : if the motions, therefore, dorsad and sternad, be made exactly to balance their forces, the motions atlan- tad only will remain, and carry the body directly upv v r ards; on the other hand, if the respective mo- sternad and dorsad be unequal in force,, the GENERAL OBSERVATIONS. 293 '?)ody, at the time that it moves atlantad,will like- wise move either sternad or dorsad. That these illustrations by the help of the figure might be less complex, the .vertebral column is supposed for the while to continue inflexible, and by its extension on the point D to >be capable of~ forming a straight line with the femur and tibia ; on this supposition, if a force were applied to the point F it would -press, directly through the medi- um of the trunk on the femur and tibia to the point B. But as the supposition is without any foun- dation in nature, and as no two bones are ever known to form straight lines, or to be united by parallel sur- faces of articulation, the pressure which one bone makes upon another must always be oblique, which causes them to turn on their centres of motion, and as* their centres of motion are moveable, to diffuse the pressure generally and suddenly through the whole system, and thus counteract with admirable contrivance the dangers of concussion. . To prevent any unnecessary trouble in trying to ascertain the nature of the curves which bones de- ecriberovmd moveable centres, it may here be obser- ved, that the curves DI and EFare merely the curves which bones describe in particular circumstances; and that with the assistance of moveable centres' the bones may be made, if properly directed, to describe any species of line whatever, as must be evident from the motions of the hand, that can be made to follow any line, whether straight or cur- ved, that can .possibly be drawn. GENERAL OBSERVATIONS, In these changes it is scarcely necessary almost to remark, that where any balancing of the body is required, the flexions and extensions must be al- ways accommodated to the centre of gravity, or the centre of gravity to the flexions and extensions. The variety of modes, the prompt celerity, and the wonderful exactness with which these accom- modations are effected, are not among the least sin- gular phenomena of the animal economy, and are often found, amid the changes of attitude and place, to characterise not only the individual, but the species. That length of neck which is neces- sary to a great number of animals in procuring their food, is regularly employed by the same ani- mals in balancing their system : and even the most careless observer may have seen that birds employ it in changing the centre of gravity from their legs towards their wings, or from their wings towards their legs, according as they choose to walk or to fly. Should it be asked, how, amid the changes in the lengths of lever, and thq varying degrees of contractile power in the different muscles, any ge- neral motion should be continued with the same force, velocity, and steadiness from its commence- ment to its termination ? it may be replied, that the yital principle, to a certain extent, can regulate its- energy according to circumstances ; that no change of attitude or place is ever produced in the osseous structure of the human body merely by the action of a single muscle ; that while one muscle is gradu- ally losing a part of its lever, another muscle con- GENERAL OBSERVATIONS. 295 cerned in the motion is often at the time receiving an addition to its length of lever ; or, in short, that the bone, in passing beyond the sphere of action that is destined for one muscle, is often en- tering the sphere of action that is destined for an- other, arid the motion continued without any change of velocity or force. This consequence is partly the effect of a difference of length, con- tractility, and position in the muscles that co-ope- rate, and partly the effect of some other causes. Some muscles pass over one joint, some again over two or more, while the muscles that pass over most joints are, in every region where they are si- tuated, necessarily also the most superficial. In the neck and trunk, those that pass over several joints are flexors or extensors, according as they bring the parts of their insertion to the perpendi- cular, or carry them beyond it. In the extremi- ties some of them are flexors, some of them exten- sors, and some of them, again, flexors of one joint and extensors of another ; while in all cases where the joint admits of a rotatory motion, they are also rotators. From this connection with 'a number of joints, it must be evident that any change of po- sition in one of them must more or less affect the action of the muscles on the rest. Thus, when the carpus is very much bent, the Extensor com- munis digitorum manus is considerably stretched, its lever and contractility augmented, the complete exion of the fingers prevented, and the power gf GENERAL OBSERVATIONS* extending them obviously increased; and thus, too, when the femur is brought to a state of flex- ion, are the semite?idinQsus, the semimembranosus i and the long head of the biceps cntris, stretched by the hip-joint, and enabled to act with the greater energy on the joint of the knee, or, if the joint of the knee be extended, with greater energy on the joint at the hip. The most singular effect, however, of the joints on the action of the mus- .cles, is what we observe in the legs of those birds that perch during sleep. The flexor of their toes is an extensor of the joint at their heel, and at- tached in such a manner that the flexion at the heel is necessarily followed by a flexion of the toes. Whence the toes, merely from the attitude assumed, and without any kind of voluntary ef- fort, are made to lay as firm a hold of the branches while the animals are asleep as while they are awake ; a circumstance noticed and explained long ago in the celebrated work " De Motu Ani- malium." The long muscles seem principally intended to preserve a connection between the functions of the several joints over which they pass. Thus, were any of the joints of the vertebral column either to be bent or extended singly by short mus- cles, and the parts in motion to pass through ma? ny degrees of a circle, the spine itself and the spi- nal marrow would be constantly in danger from the quantity of .motion, and from the extensive change of position in the parts- affected ; and. GENERAL OBSERVATIONS. were any of the large joints of the extremities to be bent or extended without any change what- ever upon others^ the balance of the body would be often overturned, and our intentions in volunr tary motions rendered ineffectual. To change, therefore, and to fix the attitudes with steadiness and accuracy, not only is it necessary that the lengths, forms, and positions of the muscles, but that all the various forms of the joints, should be mutually accommodated to one another; and hence it is, that the functions of the joints are not only closely and accurately connected, but all the joints so adapted to the muscles, and all the mus- cles so adapted to the joints, that amidst some milli- ons of possible relations which they might have had, the particular relations which they actually have are the only relations, so far as we can judge, that could have rendered them fit to co-operate, or rendered jhem subservient to the influence of the will; and yet these relations, numerous, and minute, and intricate as they are, are, so far as essential, re- gularly preserved from birth to maturity ; for as the bones grow in size and in strength, so grow the muscles, their carneous fibres, their tendinous fibres, their veins, their arteries, their cellular mem- brane, absorbents, and nerves : so that, free front disease, and free from the natural infirmities of age, the voluntary muscles, when properly direct- ed, are capable of performing their functions with steadiness in all the different periods of life. Nor let this view deter us from the patient study of GENERAL OBSERVATIONS. the muscular system ; the joints, the bones, and the muscles themselves, are easily remembered : and it seems to be here, as in all other cases where the author of nature chooses to employ secondary causes, the separate agents, in number, are but few ; and that immense Variety' of effect, by which they as- tonish every observer, does not so much arise from their number as from the infinite variety of modes in which they are made to combine their opera - tioris. On examining^ the structure of the animal sys- tem, we generally find, that the motions of the bones, as produced by the muscles, are the com- bined effects of different forces; and that hence a small number of muscles are enabled to produce with steadiness and accuracy an almost infinite variety of changes. B K A F Suppose that AB is a bone moveable in two di- rections, and that E^ and F/i are two muscles ; it must be evident, that by lengthening, and shor- GENERAL OBSERVATIONS tuning, and by varying their relative degrees of force, they may change its situation to AC, to AD, or to any given point in the circumference, and there arrest it by balancing their actions. As for the correctness with which they are able to produce these effects, suppose the circumference to be twenty-four inches, that each of the inches is equally Divided into twelve parts, and that the bone may be arrested at each of the divisions* which we know to be possible ; with what accura- cy must the muscles contract towards the centre, in order to regulate their extent of motion, with so much precision, towards the circumference ! In producing the several musical notes, by changes on the small aperture of the glottis^'or in balancing the body on the tight and slack ropes, we know that the muscles must contract with such minute- ness and Accuracy, as frequently to regulate their extent of decurtation by smaller measurements than the two hundred thousandth part of an inch. But to returfi to the changes of position ; suppose a bone susceptible! of motion in no less than four general directions, and its motions regulated, not by four, but by six, eight, or by ten muscles, all of them capable of combining their actions, and all of them capable of varying the force, the extent, duration, and order of succession of these actions, whenever it is willed, their variety of effect must be almost incalculable ; as we may see in chan- ging the positions of the os hyoides, humerus, &c, In the regulation, however, of these motioiis a smaller number of muscles than four can never ibe employed ; and even these must be employed In different capacities to produce their effects with steadiness and .accuracy. Let us take for example the motions of the head, the motions of the neck, or the vertebral column as far as the sacrum .: these parts may be inflected in any given line of di- rection, sternad, dorsad, dextrad, or sinistrad. Sup- pose that they are to be inflected sternad; there must be muscles, not only to move' them in the sternal direction, but also muscles to prevent incli- nation dextrad or sinistrad : and, as the parts may be moved again in the opposite direction, there must also be muscles to act as antagonists or mo- derators to those which carry the parts sternad. In every motion, therefore, of the head of the ver- tebral column, or of bones that can be jnoved in several directions, there must always be a number of muscles employed, some as motors, some as di- rectors y some as moderators. And yet still aur iEtentions, m producing these motions, could seldom be executed with much pre- cision, unless the parts by which the organs in mo- tion are supported, and the parts whence the mus- cles derive their origin, were to be kept compara- tively steady : it is hence that, in changing the po- sitions or attitudes, a number of muscles not em- ployed as motors, moderators, or directors, are em- ployed asjixors. Lastly, as all the motions that vary the position of the head, neck, trunk, and extremities, must likewise vary the centre of gravity, a number of muscles musfr be thrown into action merely on purpose to preserve the equilibrium, if a person be either sitting, or standing, or moving from one place to another: these muscles, if a name were necessary, might be called librators. In general, we are not conscious of theix action, unless when a state of morbid sensibility happens to show a connection between them and the muscles employed in changing the positions ; or unless, when happening to perform a motion which we did not intend, we are under the neces- sity of falling to the ground ; or of all on a sudden changing the librators with a violent jerk of the whole system, and then we are surprised how mus- cles, so distant and of such a number, should be concerned in merely changing the position of a- part. It is from the general and prompt co-operation of the different muscles in harmonizing ihefexions and extensions, the fixations and librarians through- out the se\ 7 eral parts of the system, from the yield- ing, yet steady flexibility of the joints, from the oblique apposition of their surfaces, from the angles, the curves, and the varied direction of the bones united by articulation, and from the elastic sub- stances interposed, that the "system is enabled to Desist 5.0 successfully the violent concussions to GENERAL OBSCURATIONS. which it is exposed in running, leaping, in stop- ping suddenly, or in falling from a height, By these contrivances, under the direction of the vital principle, concentrated forces are so admirably and suddenly disposed and diffused throughout every part, that even the functions of the most de- licate are, in ordinary cases, seldom impeded. To these, therefore, more than to the strength of the bones and the muscles, are we frequently indebted, in cases of concussion, for the safety of the viscera contained in the cranium, thorax, and abdomen ; for the safety of the blood vessels, nerves, and absorbents ; and even for the safety of the bones and the mus- cles. This must be obvious from the violent shocks to which men are exposed, from the want of libration, when they are intoxicated; from the violent jerks which we often receive in attempting suddenly to recover our balance; from the distor- tions of the joints and the bones in cases of rheu- matism $ from the great number of luxations and fractures arising from unequal action in the mus- cles, when not prepared to meet with the acci- dent ; and also from the practice of bending iron bars over the fore arm when the muscles are every way prepared for the resistance. That the muscles may be always ready to act on the shortest notice upon every emergency, we have mentioned already that they always are endowed with an irritability, and always possess a certain ' of the vital energy; for it must not be GENERAL OBSERVATIONS. 303 forgotten that their relaxation, in cases where they are said to be relaxed, is still, comparatively, a. state of energy, and is to be compared with some one or other of their former states, or with the state of other living muscles, and never with that state of relaxation which a muscle exhibits in the dead body. Another circumstance, that adds considerably to their promptitude of action in changing the posi- tions and in varying the diagonal, is their power of acting in different directions. And here let us take the muscles of the head, the neck, and the trunk by way of illustration. As the skeleton is divisible into similar halves, -and as all the muscles moving the head, the neck, and the trunk, are, with few exceptions, situated cither on one side or other of the mesial plane, every muscle belonging to a pair, and affixed to the head, the neck, or the trunk, must, whatever may be its remaining functions, draw the parts to which it is attached either dextrad or sinistrad* As all the surfaces ^f articulation between the bodies of the different vertebras, between the occi- pital bone and the atlas, or the temporal bones and basilar maxilla, either traverse, or would, if ex- tended, necessarily traverse the mesial plane, all the muscles that are calculated to affect these articula* tions must, between the opposite points of their at-? tachment, be directly or obliquely pointed to the; sacral and atJantal aspects 3 and consequently, be- S04 GENERAL OBSERVATIONS sides drawing the parts to which they are attached dextrad or sinistrad, must draw them likewise atlan* tad or sacrad. And as all the muscles that run between the sa- cral and atlantal aspects generally observe a degree of obliquity between the sternal and the dorsal as- pects, and are generally situated either sternad or dorsad of the centre of motion, besides drawing the parts to which they are attached atlantad or sa- crad, dextrad or sinistrad, they must draw them al- so, if not otherwise prevented, either sternad or dorsad. In many cases, especially in the sacral and at- lantal extremities, the particular direction in which several muscles act upon the bones is regulated by trochlear ligaments or pulleys, by fasciae or lateral muscular connections; while in all cases it oughi to be remembered, that whatever be their course or lateral connections, no muscles, in producing the natural changes of position, produce any chan- ges of which the joints are not previously suscep- tible from their mode of articulation and ligaments. The articulations, therefore, and ligaments become necessarily an object of attention with every myo- logist ; they often assist him in ascertaining the mo- difications of the muscular functions, and they even serve to point out a function different from any that has yet been mentioned. All articulations are surrounded with a certain, species of ligament denominated cafsular. This GENERAL OBSERTATIONS. ^05 species of ligament has a smooth surface on its central aspect. From this surface a fluid is secre- ted to lubricate the joints ; and when this fluid is defective in quantity, either from the size of arti- cular surface, or the frequency, vigour, and extent of motion, the capsukr ligament, which does not permit any fluid to escape except by absorption, is in these cases always assisted by a mucous gland lodged within the cavity, and attached to one or other of the bones, which contribute by their mo- tion to assist its action and augment its secretion. To the peripheral aspect of the capsule, the mus- cles, particularly at some of the joints, are attach- ed in their passage : and it has been observed, rhat where this attachment is found to take place, the capsule is like cellular membrane conden- sed ; and that where it is not observed to take place, is thickened or supported by ligaments from with- out. From these facts it seems to be evident, that the muscles are the principal security of the joints; and that the thickening of the capsular li- gaments, and the presence of other accessory li- gaments concerned with the joints, are substituted only where muscles are wanting, where they could not act, or where they would have occu- pied too much space. This opinion is confirmed by the strength and by the security which every joint derives from its muscles, and especially by the manner in which the scapulae and trunk are U 306 GENERAL OBSERVATIONS. connected in a great variety of the lower animal^, by muscles alone, without articular surfape or li r -gament. As for, the two crucial ligaments within the kne$ joint, their office, in some respects, is peculiar j they allow the femur to roll tibiad or inward, but notjihi/ad or outward ; and the reason is obvious we can easily arrest the rotation tibiad by placing 1 the other foot upon the ground; but if the .crucial li- gaments were wanting, we could not arrest the ro r lation jibitlad without leaning against a support, or instantly falling. As for the velocity with which muscles contract, it is, like their force, regulated by circumstances that fall not within the rules of calculation. It seems to be different in different muscles, though in all cases it partly depends upon the rapidity with which the stimulants succeed one another; and that rapidity, so far as the functions of the nerves are concerned, is increased by habit. If the celebrated Haller could distinctly articulate one thousand five hundred letters in the space of a minute, the changes induced in the state of the muscles during that period must, reckoning the contractions and the relaxations, have amounted at least to three thousand ; and yet these changes are slow when compared to the changes induced _in the muscles of a fly, where sometimes the wings are known to produce a sound as acute as that of OBSERVATIONS, 307 the most rapidly vibrating cords ; and slow when compared to the motions that take place in draw- ing a straight line with the hand a line compo sed entirely of points which belong to circumfe- rences of as many circles; and where every point, of which there may be thousands in a second of time, implies a change in the centres of motion ; a change not induced from any necessity of co-ope- -ration, but merely from the influence of -habit and PART III. CONTAINING DIFFERENT ARRANGEMENTS OF THE MUSCLES, AC- CORDING TO THE MOTIONS IN WHICH THEY CO-OPERATE; AND OCCASIONAL EXPLANATIONS ALSO OF THE MANNER IN WHICH THEY CO- OPERATE, . INTRODUCTION ) IN treating of the several motions of the system^ the least attention to consistency of arrangement must suggest the propriety of following nearly the same order that has been adopted in describing the regions and muscular attachments. The order, therefore, that is here pointed out, is to begin with the motions of the head, and then to proceed to those of the neck, trunk, and extremities ; reserving till afterwards the motions of the parts not so ob~ viously included under these titles. CHAP. I. OF THE MOTIONS OF THE HEAD, 1 HE motions of the head are common or proper: The common, those in which it participates with the neck and trunk ; and the proper, those which are performed on the first of the cervical vertebra^ 312 MOTIONS OF THE HEAD, the atlas. In the proper motions the head without any sensible rotation inclined, Sternad, Dorsad, Dextrad r *r in some of the intermediate directions. In causing these changes all the muscles that are anywise concerned exert a force in the sacral direc- tion ; those which are motors drawing the points of their attachment sacrad, and consequently rai- sing or moving atlantad the parts that are situated on the opposite side of the centre of motion *. The muscles employed in performing these mo- rnay be divided into two classes; those which affect the articulation between the occipital bone and the atlas only, and those which, besides that arti- culation, are calculated also to affect others. Of this second class, some are attached to the basilar max- illa, and the rest attached to the bones of the crani- um. Of the first class, or of those which affect the articulation between the occipital bone and the at- las only, there are four pairs ? * See lever first, p. 277. MOTIONS OF THE HEA&. 313 Qn the sternal aspect. Directions of action * , Reeti capitrs intcrni minoresf, Sac. dor. laterad, Recti capitis lateralesf, Sac. s,ter. mesiad. ()n the dorsal aspect. Recti capitis postici minoresf , Sac. ster. mesiad. Obliqui capitis superiorcsf , Sac. ster. laterad. As each of these pairs has one of their halves situated dextrad, and the other sinistra*d, of the me- sial plane, in exerting a force that is sternad or dorsad, they must at the same time exert a force that is dextrad or sinistrad. In conceiving, there- fore, how the head is inclined simply sternad, sim- ply dorsad, dextrad, or sinistrad, we cannot help seeing that it must move in the diagonals offerees that are sternal, of forces that are dorsal, dextral, or sinistral; that the lateral forces, dextral and sinis- tral, must act as directors to the sternal and dorsal; the sternal and dorsal, again, as directors to the dextral and sinistral ; that the motor forces must be moderated by those of the opposite aspect, and the sacral forces, at the centre of motion, be resisted by the fulcrum J : In all cases, the dorsal muscles, * These directions are the directions of the muscular fibres from insertion to origin, or from the moveable to the fixed points j while the term sternad, substituted for dorsad, atlantad for sacrad, and mesiad for laterad, will express the course of the tame fibres from origin to insertion, or from the fixed to the oioveable points. \ Vide Os Occipitale, p. 170. J See page 303, 304* 314 MOTIONS OF THE dextrad and sinistrad, being the motors in inflec- tions dorsad ; the sternal muscles, dextrad and si- nistrad, the motor muscles in inflections sternad; and the lateral muscles, dorsad and sinistrad, ne- cessarily co-operating in inflections laterad. In conceiving how the head is made to move be- fcween any two of the principal aspects, we have only to reflect, that the muscles are capable of va- rying their forces; and that when they happen to vary their forces, they must necessarily likewise vary their diagonal ; although it must always be carefully remembered, that what is meant by the diagonal in which any part of the system is mo- ved, is the diagonal of the forces exerted on the points of attachment, not always coinciding with the diagonal of the carneous fibres, which, in ma- ny cases, are capable of exerting different forces in the same position, and which in others are ob- served to enter the tendons obliquely, while the tendons themselves have afterwards their course changed and directed by the action of ligaments. Another circumstance not to be forgotten is, that motor muscles, when they regulate the diagonal, are also directors, and very frequently the only di- rectors that we have to look for. From the course here of the dorsal pairs, of the rec- tipostici, and obliqui super lores, one might at first be induced to imagine that they were intended for ro- tatory motions ; but the nature of the joint hardly ad- mits of that kind of motion in a sensible degree : and, besides, the course that is here observed by these, MOTIONS OF THE HEAD. 315 four muscles, is also the course that is best calcula- ted, not only for the motions of flexion and exten- sion, but for fixing the attitudes with steadiness and accuracy when the head is rolled, through the. medium of the atlas, on the vertebra dentata. As the joint between the os occipitis and atlas scarcely admits of rotatory motion, so the joint between the atlas and vertebra dentata, which is fitted both by its form and its muscles for ro* tatory motions, admits but sparingly of flexion and extension, owing to the length of the tooth- like process, its moderating ligaments, and the strong ligament that stretches across it on the dor- sal aspect. If rotatory motions were to be admit- ted immediately sacrad and atlantad of the atlas, it is natural to think that they would be performed by the same muscles ; for were they performed by muscles separate and independent, the head might occasionally be rolling one way, and the atlas an- other, at the same time, which never could take place without the most imminent danger of luxa- tion ; a danger, certainly, to which one or other, er both, of the joints would be constantly exposed* Now, instead of this, the Author of Nature has as- ^igned rotation to one of the joints, excluding in- clination; and inclination to the other, excluding rotation, and excluding it, not only by the mode of** articulation, but by the direction and action of its muscles. Of the second class of muscles, those attached te *he basilar maxilla consist of five pairs. 31(5 MOTIONS OF THE On the sternal aspect. Directions of action. JLatissimi colli*, Sac. dor. laterad. Bivcntres maxillae*, Sac. dor. laterad. At. dor. lateral Mylo>byaidei*, Sac. stcr. mesiadf. Genio-hyoidei*, Sac. dorsad f. Genlo-hyglossi *, Sac. dor. lateradf. These muscles, in opening the mouth, depress the maxilla with considerable force ; and when the maxilla happens to be fixed by the temporales, the masseteres and the pierygoidei must exert their force indirectly on the head, and co-operate with the muscles that move the head and the neck ster- nad. In these cases, the latissimi colli act indepen- dently of the os hyoides ; while the biventres, the my- idei^ the genio-hyoidet) and geniQ-hijoglossi\. * Vide Maxilla Basilaris, p. 176. f Very little sacrad when the base of the maxilla is on a plane at right angles to the axis of the neck. J All the fibres of these muscles are at one extremity attach- ed to the maxilla j only a few of them originate directly from the os hyoides, the rest originate at the mesial line, dermad of the two gemo-byo'tdel) and seem to act on the genio-hyoidei as the lateral muscles of the abdomen act upon the recti, or as the car^ neous fibre on the tendon. P. 274. Besides depressing the basilar maxilla, and regulating the positions of the os hyoides, they co-operate with the sternal half of the biventres, and also with the two latissimi colli, in supporting the tongue, and all the ba- silar part of the mouth from the symphysis mcnti to the os hy- oides. y The fibres of these evidently radiate from the basilar msuT Ht to the tongue and os hyoides : those- radiating to the os "by-* MOTIONS OF THE HEAD. require the os hyoides to be fixed or drawn sacrad by the Omo-hyoidei, Stcrno-hyoidei, Thyro-hyoidei. The latissimi colli, which, as muscular fascise, com- press the glands, the nerves, the blood vessels, and the absorbents on the lateral parts of the face and neck, may, besides depressing the basikr maxilla, and bending the head in the sternal direction, oc- casionly act as rotatory muscles in moving the head dextrad and sinistrad on the vertebra dentata. From this office the remaining muscles, however, are excluded; as none of them extend over the joint on which the rotatory motions are performed, and as none of them can possibly move the parts to which they, directly or indirectly, must necessarily at the same time owe their fixed po.ints. As for the action of the biventres, these two mus- cles might depress the maxilla, were they even de- tached from the os hyoides; but without such at- tachment they could not possibly affect the head; for to move the head indirectly, through the medi- um of the basilar maxilla, the latter must 0e so fix- ed to the former as not to change its relative situa- tion; in which case, the two biventres would neces- sarily originate and terminate in bones not suscep- oidcs run nearly dorsad j those to the tongue, sacrad, atlaa tftd, dorsad, and latqftd, 318 MO? IONS OF THE HEAD. tible of motion upon one another : and therefore, without producing any change in the relative po- sition of the head and the maxilla, they could only compress the parts of the pharynx lying between the points of their attachments. But, supposing the bvuentres attached in their course to the os hy^. oides, as they actually are, and the basilar maxilla to move only along with the head ; upon the con- traction of the biventres, if the head and the os hyoides were so moveable, at the time, as to yield to their action, they must necessarily be drawn, the one to the other ; the os hyoides, if the most moveable, towards the head; or the head, if most moveable, to the os hyoides : in which case, the head and the maxilla would be moved sternad on the first of the cervical vertebras, the atlas. The remaining muscles of the second class, and which are attached to the bones of the cranium, consist of seven pairs : 0?i the sternal aspect. Directions of action. Sterno-mastoidei*, Sac. ster. mesiad. Recti capitis int. majoresf , Sac. dor. laterad. On the dorsal aspect. Pars trapeziorumf , Sac. ster. laterad. Splenii capitisf , Sac. dor. mesiad. Complexif , Sac. ster. laterad. Recti capitis postici majoresf, Sac. ster. mesiad. 'Vachelo-mastoidei*, Sac. dor. me&iad. Vide Ossa Temporalia, p. 168. Vide Os Occipitale, p. 170. MOTIONS OF THE HEAD* 33 9 In each aspect they arc here arranged in the or- der of their strata, and may be observed, like the four pairs of the first class, to run alternately late- rad and mesiad from the place of their insertion. In .their general directions- they are seen, however, like all other muscles where motions in various di- rections, are required, to differ considerably as to obliquity ; and by their decus.sations at various angles, not only to strengthen the connections of the bones, but to multiply the natural diagonals of their fibres, fty this arrangement they combine their forces in such an infinite number of ways, .and with such facility, that the parts which they move, are all moved, directed, and moderated, with but little change in the relative position of their muscular fibres, and yet, at the same time, with a rapidity, with a minuteness, steadiness, and accu- racy, that exceed comprehension. It would be unnecessary to repeat here a minute description of the mode in which these muscles co-operate ; they co-operate with, and co-operate exactly in the same manner as, the four pairs of the first class; the sternal halves inclining the head sternad, the dorsal dorsad, the dextral dextrad, and the sinistral sinistrad, in the several diagonals of their respective forces. They differ, however, from the first class of muscles in moving the neck as well as the head, and in being employed in the ro^ tatory motions when the head is rolled, through the medium of the atlas, on the vertebra^dentata. S20 MOTIONS OF THE HEAD. OF THE ROTATORY MOTIONS OF THE HEAD. THESE motions are common to the head and at- las; which, during rotation, preserve the same rela- tive position, in consequence of the muscles of the first class acting as fixors, and assisting the joint in opposing the forces that might chance to roll either of them singly dextrad or sinistrad. The joint on which these motions are performed differs from all the other joints of the vertebral column; while it scarcely admits of any sensible flexion and exten- sion, like the other joints belonging to the move- able part of the column, it has no intervertebral car- tilage or ligament to restrain the motions dextrad and sinistrad when the one bone is rolled upon the, other in a plane perpendicular to the tooth-like process. The muscles employed in producing these mo- tions are nine pairs. On the sternal aspect. Directions of action. Latissimi colli, Sac. dor. laterad. On the dorsal aspect. Obliqui capitis inferiores*, Sac. dor. raesiad. Pars spleniorum colli, Sac. dor. mesiad. and all the muscles that were last enumerated f ; ex- cepting the interni capitis ma/ores, which, like the Scaleni medii, Longi colli, Levatores scapularum. * Vide p. 178. f See page 31$, MOTIONS OF THE HEAD, and that chain of muscles which, connecting the inaxilla with the sternum and scapulae through the os hyoides, have scarcely any influence in rotation, although they be extended over the joint on which the rotatory motions are perforined. During these motions, the muscles peculiar to the head and atlas, and the muscles of the neck, from the vertebra dentata downwards or sacrad, become fixors; and thus the inclinations of the head and neck, arising from the action of the ro- tatory muscles being every where prevented, the only directions in which they can sensibly exert their forces must be laterad and mesiad; in which di- rections, if they act alternately, the head must move, without inclination, dextrad or sinistrad, on the ver- tebra dentata. But as in these motions the two halves of the same pair cannot co-operate, the mus- cles employed to roll the head dextrad are, On the sternal aspect^ Directions. X-atissimus colli*, Pester. Sterno-mastoideusfy Sinister. On the dorsal aspect^ Pars trapeziij, Sinistri. Splenius capitisj, Dexter* Splenius colli, Dexter. Complexusj;, Sinister. Rectus capit. post, major J, Dexter. Obliquus capit. inferior jj, Dexter. Trachelo-masto^ideusf, Dexter. * Vide Max ilia basilarii, p. 176. f Ossa temporalia, p k l69, $ Os occipitalc, p. 170. |j Proccssus spinales, p. 17$, X MOTIONS OF THE HEAIT. the remaining halves of the same pairs rolling it sinistrad, and the two halves of the same pairs act- ing alternately as moderators and motors. Of all these muscles employed in rotation, the principal are evidently the obliqui capitis inferio* res. These muscles, arising from the spine of the vertebra dentata, advancing laterad, and almost dK rectly,tothetwo transverse processes of the atlas, are, from their direction and the nature of the joint, ren- dered incapable of producing, at least sensibly, any inclinations dorsad or laterad ; and are therefore re- stricted almost entirely to rotatory motions : the dextral rolling the atlas dextrad, and the sinistral rolling it sinistrad. As to the recti intcrni majores, they can have but little influence in rotation, from the shortness of their lever, and from the slight degree of their obliquity. Even the two trachelo-mastoidei, from their slight obliquity, are rotatory only when the head is turned to the opposite side. For the same cause, the scaleni medii and kvatores scapula- rum, though attached to the atlas, can scarcely be reckoned among rotatory muscles, being, like the recti interni majores, defective both in obliquity and lever. With respect to. the muscles which, through the medium of the os hyoides, connect the maxilla with the sternum and scapulae, those between the maxilla and hyoides, as already has been shown*. * Vide p. too. MOTIONS OF THE HXADl 323 can exert no influence whatever in rotation ; while the sterno-hyoidei, supposing the head, the maxilla, and hyoides, to preserve the same relative positions, have not the degree of obliquity that is necessary ; and though that obliquity be not wanting in the omo-hyoidei, yet it seems to be given for another purpose, to prevent the hyoides from being carried dextrad and sinistrad with the head and the max- illa. Accordingly, during the rotation of the head and the lateral motions of the basilar maxilla, we may generally observe that the os hyoides remains stationary, and that often the tones of the voice are unaltered. The vulgar notion, that the sterno-mastoidei are the only, or principal, rotators of the head, and the project for dividing a supposed offending sterno-mas- toideus, when the head is awry fot any length of time, must, from what we have seen of the rotatory mus- cles, be a notion and project without any coun- tenance whatever from anatomy. As other rota- tors may in these cases be acting irregularly, oh what principle can an operation, that extends but lo one of the rotatory muscles, remove the dis- tortion ? Or, suppose that one of them only is in fault, and that this muscle is divided by the knife ; on what principle are we to be sanguine in our expectations as to the manner in which the sepa- rated parts are to unite ? If the space interposed between the two divided extremities be not filled X..2 $24 tfOTIONS 0** THE HEAi*. up with carneous fibres, which is not very pro- bable, and with carneous fibres of the same kind and the same direction as the separated fibres, which is still less probable ; or if the muscle, in whatever way repaired, shall, after its reunion, be longer or shorter than its fellow and antagonist of the opposite side, on what grounds are we to imagine that these two muscles shall afterwards co-operate, and moderate one another with accuracy and preci- sion ? Or if the two divided extremities shall form adhesions with either the integuments or the neigh- bouring muscles, from what data are we to con- elude, that such adhesions will not retard, rather than facilitate, the natural motions of the head and neck? Or, supposing that the two divided extremities shall so retract as never to unite, on what principle are we to explain how its fellow, that is now left without an antagonist, shall not distort the neck more powerfully than ever ? Or, suppose again the mere possibility that the muscular affection is only symptomatic ; that it may arise, like some of the occasional spasms in rheumatism, in cramp, in epilepsy, in tetanus, In hysteria, or in the tic douloureux, from a distant cause irritating the nerves,, or from the inaction and debility of the muscle that was wont to op- pose it (as muscles are frequently observed to grow rigid when not antagonized), with what confidence are we to proceed to the operation? on which of the muscles, the weaker or stronger, are we to ope- MOTIONS OF THE HEAD. rate ? and with what probability are we to inspire the hopes of a recovery ? In such cases, a circular bandage tied round the head, with a similar bandage encompasing the chest, immediately sacrad of the two axillae, and both these bandages connected by straps, in such a manner as to regulate the positions of the head and neck, and extend their effects to the functions of all the different muscles employed in regulating their motions and attitudes, would certainly, a prto-, r*, appear preferable to the operation. Yet, from these observations, we mean not to infer that the operation has never been successful. A rai dom jerk given to a watch has occasionally been f uad to restore its motions, though surely never rec, m- mended as a method that would do much C:,dit to an artist who is acquainted with the mechanism of a timepiece*. * In the tixth volume of the Duputationcs Anatomic* Selectio- ns, which were published by Haller, there occurs a paper, enti- tled, " Quasth Mtdica, Jacobo Benigno Winslow Preside, An in cognoscendis Morlis, Errores funestos vltare possit Anatcmes pa- rum duntaxat gnarus ? respondente Petro Roussin de Monta- bourg, Paris, 17*2." From that paper thr following account, respecting the distorted neck of a female, will not, I thir.k, be unacceptable to any reader who is interested in anatomy or surgery. " Mulieri cuidam, variis hyemali tempore factia itineribug, &- grotanti, ac rheumaticis hinc doloribus vehementer afflictne, col- lum adeo devenk obtortum, ut alteri humero facies obversa fu,- 326 MOTIONS OF THE HA. erit; eidemque mentum semper ita affixum, ut nunquatn, nisi mammm ope antrorsum, reduci posset, nee in situ natural! per. manere, nisi alienis detentura adminiculis. Huic afFectui cii- rando trimestre tempus impensum est. Varia interim varii ten- taverant remedia. Omnia incassum, nullus successus, nulla spes, Vocatur demum ille, qui anatomica lance singulis ad amussim trutinatis errorem dctexit, nimirum parti illsesas omnia hacte- nus adhibita fuissc medicamina, affectae vero nulla ; imo partem incolumem erronea mcdicatione ita demum tumuisse, ut vera mail sedes focusque morbi clandestinus putaretur magis magis- que. En vero, inquis, insignem turn in cognoscendo, turn in cu- rando errorem ! Causam quoeris ? Anatomes imperitos cul- pato. Viderant isti jam pridem, vel saltern audiverant, in oris hemiplegia non segrotare latus Jllud in quod tune labia ferun- tur, sed oppositum. Putaverant forsan idem in obtorto collo obaervandum fore, adeoque de latere, cui caput incubuit, nil mali suspicantes, deceperat in altero latere tumor levi tensione stipatus. C^uinam vero tumor, quaenam tensio ? Credidisses ? Nil pro- fecto nisi quod in natural! musculorum mastoideorum actiohc reciproca fieri solet, hie contigisse animadversum est. At pa- rum gnaros vel omnino imperitos anatomes errasse dc muscu- lorum horumce statu morboso, non est quod mireris. De soli- tis et nativis eorumdem functionibus, istos etiam errasse suspicio est. Musculos masto'ideos alternis vicibus capiti in alterutrum. latus tanquam circa axim colli circumagendo inservire, docet anatome, assent inspectio, probat tactus. At ne hallucineris, obliquam eorundem directionem attentus, imo cautus, obsenra. Dextro musculo sinistrorsum, dextrorsum sinistro moveri, non obliviscere. Memento Jnsuper, reliquorum musculsrum oblique duntaxat morentium parem esse machinam. Anatomes gnarum non fefellit attenta capitis ad alterutrum humerum invite con- versi, et iliac invite labentis, inspectio. Judicavit is conti- gisse paralysin in musculo mastoideo ejusdem lateris, in quod recubuit obtortum caput, alterum vero musculum masto'ideum natural! quadam tensione riguisie. Neque judicasset alitcr, MOTIONS OF THE HEAD. 327 quamvis multoties antehac observaverit altcrutrius genss pa- ralyuin, non latus in quod os tendit, sed illud a quo discedit, affecisse. Jufisit illaeso musculo hactenus applicata removeri statiin, cademque utpote convenientia imponi laeso. Cogi- tavit inveniendum fore medium, quo caput ipsamet tegrota absque sedilis, leeti, manuumque adminiculo tenere posset tantisper, dum continuata remediorum ope sanitati restitue- rentur affect partea. Cepit in arena consilium ; expeditum ac paratu facillimum ipsissimo fere momento ex anatome promisit artificium. Nee mora, cxperimentum fecit ; optimo prater cxpectationem successu. Una fidelia duos, ut aiunt, parietes dealbavit, uno bis percussit ictu. Lapsum caput ct collum ob- tortum unico instrumento et restituit, et ad .libitum movit. O secretum ! cjamitas ! Tace tantisper j non hie quaerendus Oedipus ; Davus rem acu tangeret, modo gnarus anatomes. En paucis : Fasciae longioris, parum latae, seriebus aliquot frontcm, tempora, atque imum occiput asgrotantis circu'r.dedit, facta circumductione ad latus later! oppositum. Reliquam fas- ciae portionem obliquo ductu pone scapulam ejusdem lateris retro demisit, inde sub axillam reduxit antrorsum, reductam traherc perrexit altera manu, altera prolapsum caput ad naturalem si- tum sensirn et leniter simul perducens. Simplicis experimenti auccessus duplex ; scilicet obtorto collo, non minus ac labefacto capiti, succurrit. Eadem fascia binas languentis musculi ope- rationea obliquitate fausta supplendo caput sustinuit, collum rcstituit, utrumque pro lubitu scgrotantis ultro citroque movit, habenx modo laxata, modo tracta, modo retenta. ( 328 ) CHAP. II. OF THE MOTIONS OF THE NECKJ. JL HESE motions, exclusive of the motions on vertebra dentata, consist of inflections Sternad, Dorsad, i>cxtrad, Sinistrad, and in all the intermediate directions. As for the idea of rotatory motion which is sometimes ascribed to the cervical Vertebrae that are situated sacrad of tlie vertebra dentata, it has partly arisen from a cursory view of the different inflections following one another in a particular order of succession; as when the head and the neck together are made to move as it were on a pivot, describing a cone, the base of which is towards the head, and the apex at the sacral extremity of the neck. A similar motion is observed in the humerus, when the arm is ex- tended, and the hand is made to move in a circle ; but in neither case are either the cervical verte- brae or humerus observed to turn round on theii: axis, MOTIONS OF THE NECK. A rotatory motion, similar to that between the at- las and vertebra dentata, is prevented in the other cervical vertebras, by articulation, by the length of their spines, by their inter vertebral cartilages and ligaments, by the mnsculi inter spinales, and the intertransversarii priores et posteriores, which, both from their shortness and from their direction, will resist any force that may have a tendency to roll the vertebrae dextrad and sinistrad on their own axis. At the same time, that range of free- dom in the several joints, which is absolutely ne- cessary to varied inflection, renders them suscep- tible, in a slight degree, of a lateral contortion, which, though scarcely sensible between any two contiguous vertebrae, becomes conspicuous when a number of vertebrae are moved together. It is evidently to these degrees of contortion, and to the inflections following one another in a particular or- der of succession, that we are to ascribe the optical deception which has suggested the idea of rota- tion ; an idea, certainly, which neither an accu- rate view of the phenomena, nor an anatomical in- spection of the structure, are calculated to support. The muscles by which the inflections 37* per- formed may be divided into three classes : th<. i/ist class consisting of those which act through . -e medium of the basilar maxilla*; the secor jf those which are attached to the bones of the era- See pages 316 aad 317.' 330 MOTIONS OF THE NECK. nium* ; and the third, of those which act directly on the cervical vertebrae. Of this third class, rec- koning the groups only as pairs, the pairs will su Hiount to fourteen. On the sternal aspect. Longi colli J-, On the lateral aspect, Scaleni priores f, Scaleni medii f , Scaleni postici -f-, Levatores scapularum f, Intertransversarii f, On the dorsal aspect. Rhomboidei minoresf, Directions of action, Sac. laterad. / Sac. ster. laterad. Sac. laterad. Sac. dor. laterad. Sac. dor. laterad, Sacrad. Sac. laterad. Serrati postici superiores f, Sac. laterad. Sac. dor. laterad. Sac. dor. laterad. Sac. dorsad. Sac. ster. laterad. Sacrad. Sac. ster. laterad. Splenii colli f , Cervicales jdescendentes f, Transvcrsales cervicis j-, Spinales cervicis f, Interspinales cervicis, Multifidi spinae f , That these muscles may not only move, but strengthen the cervical articulations, there is no process, spinous or transverse, in the cervical re- gions, to which two or more of them are not attach- ed ; and no process to which any two of them, not belonging to the same pair or the same group, are not inserted at a different angle J. * Sec page 318. f Vide vertebra cervicie ct earum processes, p. 173, 179 J Sec page 3 19. MOTIONS OF THE NECK, 331 As all muscles, belonging either to pairs or to groups, and which are attached to the vertebral co- lumn, must, as well as the scaleni, levatores scapula- rum, and inter transversarii, be situate^ either dextrad or sinistrad of the mesial plane, and consequently, when not prevented by antagonists, must, when acting on the column, necessarily inflect the points of their attachment in a lateral direction ; it may naturally be asked, why the scaleni^ the levatores scapularum, and the intertransversarii, should here be assigned to the lateral aspects, as if they had something peculiar in their func- tions ? The answer is, that those muscles are not well seen from either the dorsal or the sternal aspects; and that although the scaleni antici may exert some force in the sternal direction, the sca- leni postici and leuatores scapularum in the dor- sal direction, yet, like the intertransversarii and scaleni medii, they scarcely exhibit sensible action in either the sternal or dorsal directions. The rhomboidei minor es and serrati postici superi- ores have here been introduced among the dorsal inflectors of the neck, because, in cases where the ribs and scapulae are more fixed than the cervical vertebrae, to which they are attached at the oppo- site extremity, they must necessarily inflect the vertebrae dorsad. From the circumstance that muscles producing any change on the vertebral column must exert a force in the lateral direction, in summing up those which arc employed in the several inflections of the 332 MOTIONS OF THE NECK. head and neck, I shall arrange them into two classes only : the first class consisting of those which inflect sternad ; and the second, of those which inflect dorsad. The muscles belonging to the first class, or those Tyhich inflect in the sternal direction, arc, Latissimi colli Biventrcs rnaxillas Mylo-hyoidei Genio-hyoidei Genio-hyoglossi Omo-hyoidei Sterno-hyoidei Thyro-byoidei Sterco-mastoidei Kccti capitis intcrni majorcf Rccti capitis interni minores Recti capitia latcrales Longi colli , Scaleni antici. The muscles belonging to the second class, or those which inflect in the dorsal direction, are, Partes trapeziorum. Rhomboidei minorcs Scrrati postici superiorce Splenii capitis Splcnn colli Complcxi Trachelo-mastoidci Cervicales descendentef Transvcrsales cervicis Spinalcs cervicis Semispinales cervicis Multifidi spin a? capitis postici minorr s MOTIONS OF THE NBGK. l Recti capitis postici majore* Obliqui capitis supcriorea Obliqui capitis inferiores Scaleni postici Levatores scapularum. From these enumerations the intertransversarii and scaleni mcdii have been excluded, as they properly belong to neither the sternal nor the dorsal aspects, with respect either to situation or function ; though, if I were to class the scaleni medii with ei- ther the dorsal or the sternal muscles, I should, from the instances which I have "seen, be rather inclined to class them with the dorsal. In the la- teral inflections of the head and neck, they are but a part of the muscles employed, and only assist the half of the sternal, and the half of the dorsal, on their own side of the mesial plane. As the muscles which inflect the head and the neck, by acting through the medium of the os hy- oides, can never exert a force that is greater than the joint forces of the sterno-hyoidei, omo-hyoidei, sterno-thyroidei, and thyro-hyoidei, w are naturally led to make the inquiry, why the dorsal muscles are more numerous, more powerful^ and many of them possessed of longer levers, than their antago- nists which are situated sternad? In making this inquiry, the following circumstances will almost unavoidably present themselves on the slightest ob- servation. In the erect position of the neck, when the head rests on the cervical vertebrae, with its base at right angles to the axis of the trunk, its $34 fcfdTIONS Of THE NECK. centre of gravity falls sternad of its centre of mo- tion ; and hence it is evident, that the muscles si- tuated on the dorsal aspect have not only to mode- rate the sternal muscles, but to counteract the ef- fects of gravitation; and as gravitation operates constantly, the dorsal muscles must also counteract it with comparatively small degrees of exertion, that they may not be fatigued when the head is continued long in that posture. Were the cervi- cal column to be placed horizontally, even these muscles, strong as they are, could not support the weight of the head for any considerable length of time, without being liable to pain or uneasiness. And therefore, in quadrupeds, where the neck is near the horizontal position, the dorsal muscles arc always assisted by two ligaments, which are natu- rally insensible, which arise from the spines of the dorsal vertebrse, and which run in contact, parallel and atlantad, to be attached to the cervical spines, and to the inial part of the occiput. At the same time, the head and the neck are often inflected a- gainst vigorous resistances on the dorsal aspect, but seldom against any similar resistances on the ster- nal aspect. This obvious difference, with respect to strength, lever, and number, between the muscles of these two aspects, seems to be the reason that, in cases of tetanus, where the distribution of the ner- vous energy is no longer influenced by the will, the neck is powerfully inflected dorsad, and it and MOTIONS OF THE NECK. 335 the diaphragm made to]sympathise, from their con- nection by the phrenic nerves. A similar diffe- rence, in point of strength, exists between the mus- cles that open and shut the basilar maxilla, and between the muscles on. the rotular and popliteal aspects of the legs ; where the stronger muscles, on the slightest derangement in the distribution of the nervous energy, are liable to spasms, from the want of antagonists sufficiently powerful to moderate and oppose them. The following figure is meant to illustrate how muscles, situated on the dorsal aspect, may 'exert a force in the sternal direction, and yet, notwith- standing, inflect the parts dorsad. At. Dor. Ster. Sac. Suppose that the four sides of the square repre- sent four of the principal aspects, the atlantal, .$a* 336 MOTIONS OF TH$ NECK* cral, sternal, and dorsal ; that AB and BD are twe vertebrae, BE and DC their spinous processes ; that AB is fixed, BD moveable on the centre B ; and that it is moved by the muscle MC, exerting a force sacrad and sternad towards its origin at the point M: it must be evident, that if MC contract to the length of M c, it must necessarily bring the vertebra BD to the situation of the dotted line B d, which, in every part, except at the centre, is dorsad efBD. ( 33? ) CHAP. III. OF THE MOTIONS OF THE TRUNK, JL HE trunk may be moved on the head and neck, and upon the atlantal and sacral extremities. But the motions which previously demand our atten- tion are those performed on the head of the sa- crum, and upon the dorsal and lumbar vertebrae; which, like those of the neck sacrad of the atlas, consist of inflections Sternad, Dorsad, Dextrad, Sinistrad, and in all the intermediate directions. As for the motion that is termed rotatory, and of which some of the vertebra of the trunk have been thought susceptible, it is a motion so very imperceptible, that one should hardly be accused of scepticism although he were inclined to doubt its existence. If we only reflect on the great length of some of the processes of the dorsal vertebrae ; how their spinous processes are closely connected by short Y 338 MOTIONS OF THE TRUNK. carneous or tendinous fibres ; how their transverse processes are articulated with the ribs; how the bodies of most of these vertebrae are articulated with four; how these ribs, from the decussa- tion of the two strata of the inter costales, and, from several strong muscular attachments, are, except when they change their degrees of inclination to the axis of the trunk, prevented from sliding dex- trad and sinistrad, it can scarcely be imagined that much rotation ever takes place in the region of the thorax. And as for the rotation which has ge- nerally been ascribed to the vertebrae of the loins, it has, I think, been ascribed too hastily, without the necessary investigation, and without any clear satisfactory evidence. Independent of the strength, the closeness of adhesion, and the little elasticity in the ligamenta antica and postica ; independent of the strength and the shortness of the fibres in the ligamenta intervertebralia ; and independent of that decussation observed between the fibres of conti- guous strata *, the slightest inspection of the lumbar vertebras may satisfy the mind that their oblique or articular processes are calculated to check, rather than to favour, rotatory motion. Should such a motion, however, be inferred from the oblique direction of the muscles, it need only * The ligamenta intervertebralia arc composed of numerous concentric strata-. MOTIONS OF THE TRUNK. 339 be observed, that a similar articulation of the bar vertebrae, and a similar obliquity of the abdo- minal muscles, are to be met with in numbers of quadrupeds, where the rotatory motion never takes place, and where it is evident would not on- ly be useless, but attended with danger. In short, the remark concerning the recti postici minores and obliqui capitis superiores*, may fairly be extended to all oblique muscles. Such muscles produce rotatory motion only in cases where the joints ad- mit of it, and only when made to act alternately in opposite directions. Wherever the ligaments and articulations are so formed as to resist these kinds of motions, oblique muscles are at all times thrown into action, so as to produce diagonal mo- tions ; by which means, that very obliquity which would, in cases where they acted singly, have ena- bled them to produce rotatory motion, enables them now only to resist it with the greater energy, The opinion concerning the rotatory motions of the lumbar vertebrae seems to have arisen, like that concerning the motions of the neck, from a kind of optical deception, which not only has led many anatomists to overlook the nature of the joints, but to explain the obliquity of the mus- cles on a false hypothesis. On requesting some gentlemen, who believed implicitly in these rota- * Seepage 314, 315. Y2 340 MOTIONS OF THE TRUNK. tory motions, to exhibit a specimen, I generally ob*~ served, that at first they insensibly rolled the head and moved the shoulders, the one of them< backwards and the other forwards, as if they had been rolling them along with the trunk on the lumbar vertebrae. But on pointing out the source of their deception, and on- causing them afterwards to continue their head, their neck, and their shoulders in the same rela- tive position to the trunk, and at the same time to guard the trunk against every inflection, I never could perceive in their future attempts any thing resembling rotatory motion, excepting a slight de- gree of rotation on the heads of the femora. This slight rotation, however, they asserted, proceeded necessarily from the lumbar vertebrae, as they pro- duced it not only when standing, but while they were sitting, and while the pelvis, as they thought, must have been stationary, resting on the t-w tu- berosit-ies of the ischia. To remove any doubts, and to- convince them of what was the fact, I pla- ced fr rod' of some feet in length across the sternal aspect of their ilia; and so attached it, through the medium of their dress, that the slightest rotatory motion of the pelvis, must have been indicated by the end's of the rod, which moved round in a lar- ger circumference than any peripheral part of the pelvis. With the rod thus attached, they attempt- ed again rotatory motion on the lumbar vertebrae ; but no motion of the kind was perceived, that was not easily, by the help of the index, traced to MOTIONS OF TKE TRUNK, ihe joints where the femora and .pelvis mutually roll upon one another. As men, however, gene- rally feel a sort of reluctance in renouncing an opinion that has Jong.been a favourite, and which their own observation -has confirmed, they insisted that the joints of the lumbar vertebrae admitted of contortion as well as the cervical ; and that this contortion, particularly in dancers, vaulters, and tumblers, and persons accustomed to feats of agili- ty, might be often so extensive .as to deserve the name of rotation ; and if rotation in one degree, why not also rotation in another. To this rea- soning I could only reply, that if rotation and con- tortion be- distinct, the distinction ought to be ex- pressed in language ; for although, .to .prefer a vague term to one that is .accurate be often con- venient to suit an hypothesis, it never is necessa- ry to the interests of science,. My apology to those who may think I have dwelt longer than necessary on these motions of the lumbar vertebras is, that Wuislow entertained a different opinion* ; and to differ from Winslow hastily and rashly about the function of a joint or * Les portions superietires et anterieures de 1'obliqucexterne or the ligament of Fallopius ^ and says that he has found them sometimes wanting. Sabbatier denies that Fallopius has ever mentioned such a ligament ; and Portal, on the contrary, asserts that Fallopius has described it much more accurately than Pou- part. " Le ligament inguinal, ou ligament de Fallope, qui'l decrit le premier, est line bande ligamenteuse ou aponeurotique attachee par un bout a 1'epine anteriewre superieure de 1'os des iles, et par Vautre a 1'epine de 1'os pubis. II est fort etroit le long de ses portions moyennes, et s'elargit considerablement vers ses extre- mitcs. II est fortement uni aux muscles du bas ventre, et a i'enveloppe aponeurotique de la cuisse. Souvent il paroit man- quer, comme je ferai remarquer dans 1'exposition de ces mus- cles." WIN SLOW. Traite des Os Frais, % 119. " La partie de 1'aponeurose du grand oblique, qui 1'etend de- pins le pubis jusque a 1'epine .anterieure et superieure de la crete des os des iles, ne tient a rien qu'a Penveloppe aponeuro- tique du muscle dela cuisse qui est connu sous le nom de fascia fata. Le rebord qu'elle forme est epais, qui paroit venir de ce qu'ellc est, pour ainsi dire, repliee sur elle meme, de devant MOTIONS OF THE TRUNK. 3.51 doubled on itself; and being attached, where the doubling commences, to the fascia of the thigh, and likewise, through the medium of a cellular membrane, to the integuments, where their surface en arriere, et dc has en haut. Cc bord, a Papparence d'un li- gament, et porte effectivement le nom de ligament inguinal, ou dc Poupart, de celui d'un anatomiste Frangois, auquel on en attribue la across from ilium to ilium on the central aspect of the two recti, the recti and the lateral muscles could no longer have acted reciprocally upon one an- other as upon pulleys ; the epigastric arteries and veins must have passed through a tendon, their functions been less dependent on the recti, and the recti never have been drawn dorsad beyond the sternal and atlantal processes of the ossa ilia. The use of the pyramidales is best seen by exa- mining the recti on their central aspect ; for where the pyramidales are present, a triangular space, occupied by transverse tendinous- fibres, is generally observed between the recti : hence the two pyramidales, which not only shorten the linea alba, but compress a little the viscera of the pel- vis, necessarily co-operate with these fibres in resisting the separation of the recti, and pre- venting hernia. For a similar reason, the parallel fibres of the obliqui externi are held together by the strong decussating fibres of their aponeurosis ^ the attachment of the recti extended later ad on the spines of the pubis, often as far as the ligament of Gimbernat, and their adhesion greatly strength- ened by a periosteum, that usually exhibits the appearance of tendon. Partly, too> for the same reason, the fibres of the lateral abdominal muscles are observed to run in different directions, prevent- ing not only the protrusion of the viscera by theic MOTIONS OF THE TRUNK. 553 decussations, but by their obliquity acting at the same time as motors and directors, and performing a greater extent of motion by a less proportional degree of contraction than if they had taken a short- er course between the bones to which they are attached at their opposite extremities. In all inflections, laterad or sternad, the levers by which the obliqui and recti act upon the vertebra^ through the medium of the ribs, are lengthened or shortened according as the ribs are elevated or de- pressed. When the thorax is expanded laterad and sternad, the planes of both the obliqui and recti are in these directions necessarily removed to a greater distance from the centre of motion ; and ^ice 'versa when the ribs are depressed. Hence one of the reasons why all the vigorous inflections of the trunk are preceded and accompanied by full inspirations. The obliqui externi and obliqui interni, from oc- cupying the whole of the lateral aspects, extend- ing between the ilia and ribs, and from acting at the greatest lateral distance from the centre of mo- tion, must always be muscles principally concerned in producing inflections dextrad and sinistrad on the lumbar vertebrae, principal directors in all the inflections sternad and dorsad; and from the assist- ance which they give to the recti, principal libra^ tors also of the trunk, whether we be sitting, stand- ing, or walking. When any of these muscles, herefore, are injured; or morbidly sensible, there are 356 MOTIONS OF THE TRUNK* few of the usual inflections or attitudes belonging to the trunk that are not accompanied with more or less pain. In such circumstances a man is com- pelled either to desist from most of the ordinary duties of life, or to find out a method by which he can perform them without those exertions of the injured muscles by which the pain and uneasiness are excited. Of the two alternatives, to continue the usual employments of life is the most desirable; and it certainly is the business of both the patient and his medical adviser to try if such an object be attainable. Some years ago, a man, in attempting to recover his balance with a weight upon his shoulders, in- jured these muscles between the ribs and the crest of the ilium. Unable to continue any longer at his work, he walked home with excruciating pain, went to his bed, and laid himself down on the side that was sound. When I saw him a few hours after, he told me that the pain which he felt in lying down was past all description ; that he then could not venture to change his position, although his whole house were in flames ; and that he was almost perfectly assured that his back was either broken or disjointed. Notwithstanding the pain which he dreaded, I prevailed upon him to allow me to change his position to the injured side ; and pla- cing myself in a similar position, I showed him how to rise to the sitting posture without bringing the injured muscles into any strong action, then MOTIONS OF THE TRUNK. 357 !how to stand, at last how to walk, and how to lie down again; which he readily did without much pain, and soon after without feeling any, to his own surprise, and the great joy of his wife and family, who a little before, from viewing his case as incu- rable and hopeless, had been figuring him in his last struggles with death. On putting the ques- tion, whether or not he could move the arm of the injured side as freely and extensively as he did be- fore ? he answered, that the arm had never been affected. But on my taking hold of it, and sud- denly raising the point of the elbow as high as the head, he uttered a scream that alarmed the neigh- bourhood. The cause of this pain was to be as- cribed, not only to the common attachment of the latissimus dorsi and obliquus intermix in the spines of the vertebrae, but to the -connection of the latissi- mus with the obliquus externus in the ribs, and to a sudden, though a slight exertion of the inju- red muscles in preserving the balance when the centre of gravity was somewhat changed. A proof, that in cases where the muscles are injured and the motions impeded, we ought not entirely to confine our views to the seat of the injury, but at- tend likewise to the various muscles related by at- tachment, contiguity, or function. The effects of the injury continued for a week; and during that time the pains were frequently severely felt when the motions and attitudes that had been prescribed weie not regularly observed.. 358 MOTIONS OF TOE TRUNK. In this way, with little interruption to his usual habits, the cure was as speedy, and probably as complete, as if his whole system on a sudden had been made to undergo a general change ; as if he had been bled, blistered, and purged ; confined to bed and a low diet, and made to sleep by the help of opiates till signs of his convalescence appeared. The flexures observed in the vertebral column, and which are in general less marked in the young subject than in the adult, are produced chiefly by the action of muscles : yet not produ- ced as if they were merely accidental effects, but evidently as means adapted to an end, contribu- ting their aid in enabling us to balance the weight of the body on its centre of gravity when stand- ing or walking. The well formed vertebral co- lumn on the dorsal aspect is, for these reasons, al- ways convex from the os coccyx to the junction of the os sacrum with the ilia, then concave from that part of the sacrum atlantad to near the true ribs, then convex as far as the neck, then concave again till it reach the atlas. Had it been straight, the centre of gravity would necessarily have been so restricted in its range between the dorsal and the sternal aspects, that we could not with steadiness have supported the trunk on its sacral extremities, and at the same time have extended completely the hip and the knee joints, seeing these joints and the joint at the ancle co-operate with the cur- yatures of the vertebral column, and, like these MCTIOHS OF THE TRUNK. 359 curvatures, are also alternately concave and con- vex on the dorsal aspect. For, if it be obvious that all the parts in the opposite aspects must be in equili- bria sternad, dorsad, dextrad, and sinistrad, it is e- qually obvious that the farther they extend in the opposite aspect, provided they be manageable, the more easily and the mose readily .will the balance be maintained; .as may be seen by lengthening and shortening the .extent of the pole by which the dancer balances his body on the tight or slack rope. It is also evident, that when any part of the body is inclined to one side of .the centre of gravity, some other part, to preserve the .equili- brium, must be proportionally inclined to the opposite. Hence, throwing the atlantal extremity of the trunk considerably sternad of the centre of gravity, so as to touch the ground with the fingers, its sacral extremity must always be thrown ,pro- porticnally dorsad, and the heel and the .knee joints at the same time inflected in qpposite directions. Hence no person, with the lieels and the sacrum in contact with a wall raised perpendicular to the base on which the heels .are supported, can touch the ground with the points ,of his fingers, and pre- serve his balance ;. hence those .spines, which are ve^- ry much bent at one of their curvatures, are gene- rally found proportionally bent at some of the others; and hence those spines which, in consequence of disease, have their curvatures laterad, have them Alternately concave and convex on the lateral ,as- 360 MOTIONS OF THE TRUNK. pects, in the same manner as the well formed spines have them on the sternal and the dorsal aspects. Of the regular curvatures, that of the sacrum is occasioned by the reliance of the ilia towards its middle, the pressure of the column at one of its ex- tremities, and the force of the glutens magnus at the other ; that extending from the sacrum atlan- tad to near the true rilxs, by the vigorous and re- peated exertion of the sacroiumbaks and longisiimi dorsi, not only in raising the trunk from the hori- zontal to the erect position, but in preventing the centre of gravity from failing sternad of the base on which we stand ; that of the neck, by its dorsal muscles, which are always stronger and more numerous than those which are sternal ; and that of .he thorax, by ihe pressure of the parts si- tuated atlantad, by the centre of gravity being there sternad of the centre of motion, by the small- er size and the shorter levers, and consequently the less vigorous exertion of its dorsal muscles. This last curvature is also much increased m phthisis pul- monalis, and in many other cases of debility, where the muscles that depress the ribs are relaxed, the shoulders elevated, and several muscles not usual- ly employed in enlarging the chest, are brought to the aid of the intercostals. In such cases, it is generally observed that the balance is preserved when standing or walking by more than usual degrees of inllection in the sacral extremities ; MOTIONS OF THE TRUNK. while in advanced periods of life, when the humours are scanty, when the intervertebral car- tilages are shrunk, and the vertebral column it- self is shorter, the whole is disposed to incline ster- nad, when the knee and the hip joints are still more inflected, and, in many instances, a staff ren- dered necessary to preserve the balance. Nothing resembling the three first curvatures that occupy the sacral, lumbar, and thoracic re- gions, are in general to be found in the vertebral columns of quadrupeds or birds. From their seldom assuming the erect posture, their more usual cen- tres of gravity and centres of motion are situated differently ; and hence in quadrupeds, that remar- kable difference in the inclinations of the spinous processes of their moveable vertebras. In the hu- man species, these processes are all inclined to- ward the sacrum ; to which they are drawn in pass- ing from the horizontal to the erect position, or on which they are balanced by muscular force when they are raised to the perpendicular. To the same point we sometimes observe the first of the spi- nous processes of the sacrum inclining atlantad. In quadrupeds, again, the appearance is different, and yet evidently proceeds from a similar cause. The spinous processes of both their lumbar and their dorsal vertebras are regularly inclined to that point near the middle of the column, which forms the common centre of motion between the two ex^ tremities of the trunk that are alternately raised gnd depressed in progressive motion. &62 MOTIONS OF THE The muscles principally concerned in producing these inclinations are, the latissimi dor si, longissimi dor si, sacrolumbales, the semispinales, and multifidi spi- n& : the three first drawing the spinous processes atlantad, and the two last drawing them sa- -crad. Where they all are attached to the same processes, and where they draw with equal fre- quency and equal force in opposite directions, the processes generally project dorsad ; where the$r are inclined sacrad or atlantad, their degrees of inclination indicate the difference of frequency and force by which they are drawn in these oppo- site directions. Hence, in examining these pro- cesses of the vertebrae, we may in general be able *o determine what had been .the most usual inflec- tions of the vertebral column, what its principal -eentres of motion, what its most fixed and move- able points, and what the attitudes and changes of .attitude to which the animal, when in life, had 'been most accustomed. As these processes are likewise calculated to in- crease -the power of the muscular levers^ we are -often enabled to conjecture, from their length, where the power of the lever had been principally -employed to compensate the force and bulk of the muscles. Thus in the atlantal extremity of the tho- xax, the spinous processes are considerably longer .than in any other part of the column, if the head -be heavy, .the neck long, horizontally situated^ MOTIONS OF THE TRUNK* and comparatively slender ; or if the parts situated atlantad of the centre of motion be heavier than those which are situated sacrad, as may be seen in the skeletons of the goat, the deer, and the horse. With respect to the spinous processes of the cervical vertebrae, which, by means of the splenii, the semispmaks, and muhifidi spin Teres major, Teres minor, Triceps brachii (long head of), Latissimus dorsf. Should any be surprised why the teres minor ;4 here enumerated arfiorig the flexors, and the infra- spinatus among the extensors, considering that they are so closely united in their origin, theif course, and their termination, that Vesalius has described them as one muscle, it may be observed, that two parts of the same muscle may have different func- tions 5 or, indeed, without any reasoning or hypothe- sis, that one of these muscles is actually relaxed while the other is stretched during extension; an ef- fect that could not possibly arise from any other cause than from their acting at the same time on op- posite sides of the centre of motiori, just as two cords attached to a balance supported upon the edge of a knife, will, if they be drawn towards the knife, move the balance in opposite directions, although they be parallel and almost in contact, with no-* thing but the edge of the knife interposed. To prevent mistakes, I must here add, that all the extensions and flexions of the humerus, as may be seen iri the living body, &re regularly ac- companied with corresponding motions of the sca- pula : the base moving sternad, and the acromion dorsad, during the extension's; and vice versa, in contrary directions during the flexions, if these be Bb MOTIONS OF THE? performed in a state of adduction, or in a plane near- ly parallel to the mesial plane. If performed, how- ever, in a state of abduction, the scapula is seen jn-oving alternately dorsa-mesiad and ster-mesU laterad, with its middle part pressing on the thorax, and its head and its base moving like the two ex- tremities of a balance, alternately approaching arid receding from the ribs. The abductors* are the Deltoides, Supraspinatu*, lufraspinatus, Subscapularis, Biceps brachii r Coraco-brachialis. ft already has been noticed, that all the exten- sors, except the perforates, are calculated to move the humerus laterad /or, in. other words, in a plane approaching, to that of the scapula ; and would consequently, therefore, produce an abduction, were they not restrained by the adductors. From this circumstance, the enumeration of the extensors undof the abductors is nearly the same, with the dif- ference only, that the spino-scapulen portion of the deltoides,. from being a flexor, is not enumerated among the extensors, nor the claviculen portion of the pectoralis among the abductors. The adductors are the Directions of action. Pectoralis, At. ster. mesiad. Sac. ster. Lathsimua dorsi, Sac. dor. mcsiad** ATLANTA! EXTREMITIES* 38't When these two act with equal forces st&rnad and dorsad, they will move the humerus at right angles to the mesial plane ; or if one of them act, as the pectoralis, and draw the humerus till its distal extremity meet the mesial plane at the sternum, the latissimus dorsi, by drawing dorsad, will press the distal extremity to the thorax. On the other hand, if the humerus be drawn mesiad and dorsad by the latissimus, its distal extremity will be press- ed to the dorsal part of the thorax by the pectora- lis. None of these motions can, however, be per- formed without corresponding motions of the sca- pula, whose head, excepting in the rotatory mo- tions, generally follows to a certain extent the motions of the huinerus. When the extensors, the abductors, the flexors, and the adductors act to the sme degree of ex- tent, and also in the same order of succession in which they are inserted around the humerus, the humerus will describe the circumference of a cone, the base of which is towards the elbow, and the apdx of which extends to the scapula; the toralis moving the whole % Sacracf, Mesiad, and Sternad ; Then, Sternad, Mesiad,' and Atlfntad, Bb* 388 MOTIONS OF THE" till it come within the sphere of the extensors and of the abductors, which will move it Atlantad, Laterad, and Dorsad ; and then deliver it over to the flexors, which will move it Dorsad, Mesiad, and Sacrad ; until it again come within the sphere of the pec- toralis, which will move it round as it did before. This compound motion will serve to explain, why part of the adductors should be extensors, why part of the extensors should be abductors, why part of the abductors should also be flexors, and why the flexors should naturally run into part of the adductors. In such a motion, it must be ob- vious, that the motor forces in any given part or the circle will always be moderated by those which are opposite, and directed by those that act in a plane at right angles to the moderating forces. The rotators radiad are the Supraspinatus, Infi-aspinaUis, Teres minor, Deltoides (spinoscapulen portion), and the Coraco-brachialis (to a soiall extent, and only \rh the humerus has been rolled ulnad). The rotators ulnad are the Deltoides, (clariculen portion) $ 4 ATLAKTAL EXTREMITIES. 389 and when the hitmerus has been rolled radiad, the Latissimus dorsi, Teres major, and Pectoralis (to a small extent, however, and only at the commencement of tfce rotation). In rolling the arm, the rotators radiad co-ope- rate with the muscles called supinators; the rota- tors ulnad, with the pronators. To know, there- fore, the extent of motion which is produced by. the different rotators, let the humerus be held close to the side; and after pronation and supination have taken effect to their fullest extent, let the arm be extended in a state &f abduction, and with the eye directed to the hand examine how much of rotation is added by the muscles of the humerus, it will be found that the radial rotators add ver/ little ; the ulnar rotators often a semicircle. Considering the great variety of functions which the muscles belonging to the joint at the shoulder have to perform, and considering likewise that each of these muscles performs the different func- tions assigned to them in different degrees, it often requires no small share of attention and accuracy to demonstrate clearly their more obscure and subordinate functions. Let us take, for instance, the spino-scapulen part of the deltoides, which is a. flexor, an abductor, and rotator radiad. The method usually adopted by anatomists to ascertain the particular motions which this or any muscle had performed in the living body, is to preserve its relative situation with ad the connections that 390 MOTIONS OF THE affected its functions, and then to try, by moving the bone in different directions, to discover those particular positions in which the fibres are stretche4 or relaxed. Now the fibres of this part of the del- toides may be relaxed in a state of abduction, flexion, or rotation, and the humerus may be pla- ced in all these states at the same time ; the diffi- culty then will be, to ascertain what particular de- gree of relaxation was occasioned individually by the separate states. To know, for example, the degree of relaxation from rotation radiad, or whe- ther any relaxation is produced, the humerus must, previously be rolled ulnad, and then radiad, with- out either abduction or flexion, and without any change in the previous state of extension or ad- duction ; for if abduction or flexion take place, a relaxation may be ascribed to the rotation, which does not belong to it ; or if farther extension and adduction take place, the relaxation which would follow as a consequence of the rotation might be prevented. In short, the anatomist, in designing to produce a simple motion, may inadvertently pro- duce a compound, and ascribe the effects which he afterwards sees to the motion which he had in- tended to perform ; although the effects be the consequences of a motion which he never had in- tended, and of which he might never have form- ed an idea. In making these remarks, let it not |?e supposed that I allude to the errors of others. The diffidence I feel, and the caution I have learn- ATLANTAL EXTREMITIES. cd in examining muscles with a view to ascertain the nature of their functions, have chiefly arisen from comparing my later and earlier observations, and from detecting instances., not a few, of my own inadvertency and want of attention to minute cir- cumstances, that are apt to escape the notice of a person not practised in conducting these kinds of -experiments. In those cases where the humerus is luxated, a steady attention to the situation in which it is placed, and deliberate reflection on what muscles are relaxed and stretched, what muscles are ready to assist or oppose, and likewise what muscles, s for instance the biceps, may be affected by the flexion or extension of some other joints, must al- ways be objects of importance with the surgeon .; and if he should wonder, in attempting the reduc- tion, at the varied, sudden, and vigorous exertions which are made by these muscles, and at the great unavailing force that is not unfrequently made to overpower them, he surely cannot help being e- qually surprised at the slight causes which in some instances produce the luxation, and the small force which in other instances is required in the reduc- tion. To explain the phenomena, we have only to reflect that the bone is preserved in its situation chiefly by the muscles, and that when any of the powerful muscles are taken by surprise, and without the others being prepared to moderate and direct it, th joint must always be in danger of luxation. MOTIONS OF THE however trifling be the force or the stimulus that introduced the derangement of action. The same is the case after luxation : the surgeon, taking the patient by surprise, may often with a slight and a sudden jerk throw those particular muscles into action which favour the reduction, before the ipusples calculated to oppose them are prepared to make any forcible resistance. Thus may a slight force, properly contrived and accurately timed, do more at one period thap a great force directed by skill can do at another. As a proof of this assertion, it is not the joints that have the Hiost vigorous actions to perform, nor is it the joints that are least secured by the strength of their ligaments or by articulation, that are most liable to accidents of luxation ; it is those joints which, like the joints at the hip and the shoulder, admit of the greatest variety of motion, which require the greatest variety of action in their mus- cular forces, and where harmony amidst this va- riety of action is most difficultly preserved, from the number of rotators, motors, moderators, and 4i rectors that must necessarily act at the same time with a precise and definite force, and yet may have other functions to execute on different bones and articulations'*. Let it not be said, that in these cases the capsular ligaments perform not their * See pages 391? 302. ATLANTA! EXTREMITIES 3Q3 Office; for what, in general, is the strength of these capsules* where the muscles adhere to them? they are little more than cellular membrane ; and if the bone usually burst through them where they are strongest, and where they are least sup* ported by muscles, it will only prove that muscles are the principal security of the joint, as we may see in that connection formed between the trunk and scapulas of quadrupeds, without the interven-* feon of clavicles. SECT. IV. MOTIONS OF THE ULNA. JL HE motions of the ulna are those of Extension, Flexion, Rotation : In the two first, accompanied by the radius ; In the last, by the humerus. The connection of this bone with the radius is formed by ligaments; at its proximal extremity, by the capsular membrane, the ligamentum orbicu- lar e, and chorda transversalis ; from near its proxi- mal extremity to the distal, by the ftiembrana inter- Qssea ; at the distal extremity, by that ligamento- * See pages 304, 305, 394 MOTIONS OF THE cartilaginous substance which Weitbrecht deno- minates cartilage intermedia or trianguiaris, by the membrana capsularis sacciformis, and by those liga- ments which extend from the styloid processes of each bone, and there connect them, although in- directly, through the medium of the carpus. This connection is farther strengthened by thzfasria of the biceps, and the oilier fascia expanded periphe- rad over the muscles, collecting the whole, as it were, into a group, firmly attaching themselves to the bones, and affording an origin to several fibres belonging to the muscles. Lastly, it is strengthen- ed by the muscles themselves, and in different ways : by some of them adhering to the capsular membrane at the proximal extremity of the two bones ; by others being attached to the two bones * ; and again by others which, though at- tached but to one of the bones, yet run from the ulnar to the radial aspect obliquely across the in- terosseous space, as may be seen in some of the pronators on the thenal aspect, and in some of the extensors upon the anconal. From such powerful connections, the radius being forced to accompany the ulna, both in its motions of extension and flexion, the same muscles that explain the exten- sion and flexion of the one will explain the extcn- sioa and flexion of the other. See page 189. ATLANTAL EXTREMITIES, 395 COMMON EXTENSION OF THE ULNA AND RADIUS, THIS motion is produced by the Triceps brachii, and Anconeus; aone of which are inserted in die radius. With respect to the long head of the triceps, it feeing also a flexor of the humerus, it will act less forcibly upon the ulna, when the humerus is extend*, ed, than when it is inflected ; and, consequently, in eases where the ulna is luxated, and where the ole^ cranon is drawn proximad upon the anconal aspect of the humerus, in attempting the reduction, the humerus should be brought to a state of flexion, COMMON FLEXION OF THE ULNA AND RADIUS. THIS motion is produced by the Brachialis interims. Biceps brachii, Supinator longus, Ulnaris internus, Palmaris longus, Pronator teres, Radialis internes, Sublirais. The biceps, from being an extensor of the hume- TUS, will in this instance act with more force when the humerus is inflected than when it is extended, and will, at the .same time, meet with a less degree 396 MOTIONS OF THE of resistance from the moderating force of the long or scapulen head of the triceps'*. The ulnaris interims, and the muscles that follow, are flexors only to a small extent, and only at the time when the motion commences, before the lever of resistance is shortened, and the levers of the bi- ceps and supinator are lengthened f ; the four last having their power a little increased when the arm is placed in a state of supination, and when, con- sequently, the biceps is somewhat relaxed. The office of directors is here committed to the structure of the joint, to its accessory ligaments, to the fasciae, and to those muscular attachments that are situated on its radial and ulnar aspects. ROTATIONS OF THE ULNA, FROM the structure of the joint by which the ulna and humerus are connected, it not only is ob- vious, but proved by experiment, that a rotatory motion in one of these bones, if the ulna be ex- tended, must be necessarily followed by a like ro- tatory motion in the other. It is also obvious, and proved by experiment, that the rotatory motions observed in the hand proceed from the rotatory motions of the radius. Supposing, then, that the hand takes firm hold of an object that is not to. be See page 295. f See page 288 and 294, 295* ATLANTAL EXTREMITIES. 397 moved by its muscular force, the rotations of the jadius will be prevented, though the ulna, if ex- tended, may be made to roll along with the hume* rus. Yet in these circumstances the humerus will be rolled, not merely by the muscles inserted near its proximal extremity, but partly also by the pronators and supinators, some of which are attached to the humerus, and some to the ulna ; the pronators rolling them thenad and radiad, and combining their effects with those resulting from the supraspinatus, the infraspinatus, the teres mi- nor, and the spino-scapulen part of the deltoides ; the supinators rolling them again radiad and an- conad, and combining their effects with those re- sulting from the teres major, latissimus dorsi r the pectoralis, the claviculen portion of the deltoides, and subscapularis. If, after all, it should be observed, that the roll- ing of the ulna in these circumstances is rather obscure, the answer may be, that it is partly owing to the ligament that extends from its sty- loid process to the carpus, which is then a fixed point, and partly also to those extensors, and to those flexors of the carpus and fingers, which are then employed in another function, that forces them to oppose rather than to favour this kind of motion. In such cases, the resistance is com- municated even to the humerus; and hence it is, that we never can roll the ulna or humerus to the same extent, when the hand is fixed, as when it is totally free and disengaged. 395 MOTIONS OF THE ROTATIONS OF THE RADIUS. THESE rotations are already well known under the names pronation and supination. The pronators are the Pronator teres, Pronator quadratus, Palmaris longus, Radialis interims, Sublimis : The three last at only the commencement of the pronation, although their power, from being thenal flexors of the carpus, be somewhat increased in cases where the hand is inflected anconad, and that of the sublimis farther increased where the fingers are extended. The supinators are the Biceps brachii, Supinator brevis, Extensor major pollicis : The first acting with the greatest force when the humerus is inflected ; and the last, with the great- est when the carpus and thumb are inflected the- nad. As for the muscle which has been called supi- nator longus, it co-operates w r ith, and moderates alternately, pronators and supinators, bringing the radius to that middle state which is properly nei- ther pronation nor supination, and performing this Qffice with the greatest force when the arm is ex^ tended. ATLANTA! EXTREMITIES* GENERAL REMARK. IN both these kinds of rotatory motion, as the ra- dius must necessarily roll on the ulna, we never can suppose that the radius can roll, and particu- larly at its distal extremity, on its own axis ; nor ever suppose, considering the connections of the ulna and carpus, that the carpus can roll along with the radius, and the ulna remain stationary in its place. In every pronation, therefore, and su* pination, these two boes at their distal extremitj twist, as it were, round a common axis*. Not, how- ever, that the ulna is susceptible of rotation at its junction with the humerus, but only of a certain freedom of motion sufficient to allow its distal ex- tremity to follow the carpus in pronation and su- pination. From such an account, it is not improbable that all these muscles which run obliquely from the radial to the ulnar, or from the ulnar to the radial aspects, may have some effect on these rotatory motions, though not so extensive as to be demon- strable. in the dead body. * On attribue pour 1'ordinake ce mouvement au rayon seul. On s'imagine que Pos du coude n'y a aucune part, et on nc rcgarde cet os quc comme une piece qui sert uuiquement d'ap- pui et de base aur laquelle on fait faire au rayon ces petits tours jreciproquei ^u'gn appelle probation et supinauon. Erfb, om MOTIONS OF SECT. V. MOTIONS OF THE CARPUS. JL HZSE consist of different inflections* Anconad, Thenad, Radiad, Ulnad ; or in any of the intermediate directions. The ino- tion anconad has been called extension^ as being borne ce mouvement a Paction de qwatre muscles, ou tout au plus a cinq, en y rapportant le biceps. On pretend meme avoir vu montrer, avoir soi^meme montrc, ft etre toujours en etat de montrer clairement et d'une maniere incontestable, tant sur le squelette que sur le cadavre, ces deui mouvemens reciproques, sans aucun mouvement de 1'os dn coude. De pliw, sur cette idee, on a souveut, avec une pleine assurance", et en public et en particulier, fait ces mouvemens sur soi-mcme^ pour prouver qu'ils se font avec le rayon sur 1'os du coude, et que 1'os du coude n'y a aucune part. J'ai neanmoins observe, et je Fai demontre a 1'Academie Royale des Sciences, que dans ces mouvemens libres, et faits sans contrainte, comme autour d'une axe commun, les deux os de 1'avant-bras se meuvent toujours en meme terns ; c'est-a-dire, par exemple, pendant qu^on tourne le rayon vers la poitrine par la pronation, on en sloigne en meme terns 1'os du coude ; et re- cjproquement, quand on eloigne le rayon par le mouvement de supination, on en approche en meme terns 1'osdu coude. J'en* tends ceci dans 1'attitude de Pavant-bras flcchi. Winsloiv, & position dnatomique de la Stricture du Corj>s Humain, ii. 485^ ATLANTA! opposed to the motion thenad, which has been simply denominated flexion ; while the directions radiad and ulnad have been differently expressed by different authors, according to that particular attitude in which they have chosen to describe the forearm. When they have chosen to describe it as extended, and either parallel or inclined to the trunk in a state of pronation, their motion radiad has been motion inwards, and that towards the ul- na, motion outwards ; or when they have preferred a state of supination, their motion radiad has been motion outwards, and that towards the ulna, mo- tion inwards ; or when, with Albinus, they have preferred a state intermediate, their motion radiad has been motion forwards, and that towards the ul- na, motion backwards; Thus have the terms an- terior and posterior, interior and exterior, with the adverbs corresponding, been each employed to denote" three aspects of the forearm ; while the terrri abduction, as applied to the thumb and the little finger, is still used to Express motions in op- posite directions; a similar privilege, if such it fnay be called, having been conferred on its rela- tive adduction. The muscles employed in performing these mo- tions, are the Radialis externals longior *, Radialis externus brevJor *, Radialis interims *, See p. 189. C c 402 MOTIONS OF THE Ulnaris externus *, Ulnaris interims *, Extensor communis digltorum *, Indicator -f-, Extensor proprius minimi digiti *, Abductor longus pollicis};, Extensor minor pollicis J, Extensor major pollicis J, Flexor longus pollicis J, Palmaris longus *, Sublimis *, Profundus f . The inflectors anconad, are the Radialis externus longior, Radialis externus brevior, Extensor major pollicis, Indicator, Extensor communis digitorum, Extensor proprius digiti auriculanV, The inflectors thenad, are the Radialis internus, Ulnaris internus, Palmaris longus* Sublimis, Profundus, Flexor longus pollicfs. Yet the two first muscles in each of these classes being chiefly employed in the motions of the car- pus, they in this respect differ considerably from the other muscles, which, besides inflecting the carpus, inflect some of the digital phalanxes, and consequently act with more or less force in See p. 189. ,f P. 190. J P. 191. ATLANTA!. EXTREMITIES. 403 moving the carpus, as their contractility is more or less exhausted by previous functions. From the centre of motion being in the car- pus, as everywhere else, confined to a very li- mited space, and from some of these muscles not lying directly anconad or thenad, but somewhat to the radial or ulnar aspects, they, in bending the carpus anconad or thenad, must likewise inflect it either radiad or ulnad. The inflectors radiad, are the Abductor longus pollici?. Extensor minor pollicis, Radialis externus longior, Radialis externus brevior," Radialis interims. The inflectors ulnad, are the Ulnaris externus, Extensor proprius minimi digiti,- Extensor communis digitorum, Ulnaris intern uV Sublimis, Profundus j ihe abductor longus and extensor minor pollicif appearing to have no sensible effect on either the motions anconad or thenad, while I he ulnaris externus Seems to bring the hand from the ex- tremes of these two motions, and to carry it ul- nad. The indicator, the extensor major poHicis^ the palmdris longus, and the flexor longus pollicis, have not been introduced ; as their effect in acting on the radial or ulnar aspect is, in ordinary cases, not very conspicuous. C e 2 404 MOTIONS OF THE g= ' " SECT. VI. MOTIONS OF THE BONES COMPOSING THE CARPUS. j. HESE motions between any two bones are very obscure,, if we except a small degree of motion be- tween the pisiforme and the cuneifornie ; the pisi- forme being, as it were, a sesamoid bone belong- ing to the tendon of the ulnaris interims. The ef- fects of the whole, even when combined, are not very perceptible, either when the hand is closed or expanded ; and yet, imperceptible as they seem to "be, they are not without their use. By these mo- tions, by the lubricity of the articular surfaces, and by the elasticity of the accessory ligaments, the form of the- carpus, so far as necessary, is regularly accommodated to the different functions of the me- tacarpal and digital phalanxes. At the same time, the smallness of the motion among the whole, and between any two bones, greatly assists in enabling them to preserve their relative positions; though, should it be asked, how are they able to pre- serve this position amid the shocks to which they are exposed ? why they should be placed in such a situation? or why one bone would not have been preferable here to a number? the answers may be, that their connections are not preser- ved merely by ligaments; that there is no vi- 4 ATLANTA!, EXTREMITIES. 405 gorous exertion of the hand, or its fingers, in which they are not regularly supported by fascisc or tendons acting as motors, moderators, or direc- tors ; that some of these tendons proceeding from the forearm, run across them on their different as- pects with different obliquities, some decussating, and some, like the fibres of the aponeurosis pal- maris, diverging like radii from centre to circum- ference, and compressing them strongly upon eve- ry -side, and distad, through the medium of the metacarpal and digital phalanxes ; that in addi- tion to this support which they derive from the muscles of the forearm, ilie pulmaris brevis* is al- ways ready to give its assistance, while there is not a bone of the number, the scaphoides, lunare, and cu- neiforme excepted, that does not afford an origin to" muscles which by their action support them indi- rectly, and which by their attachment contribute di- rectly to strengthen and assist their accessory liga- ments. Had one bone occupied their place, its form could not possibly have been accommodated to all the varying motions of the hand, nor could such a bone have so readily diffused and rendered harmless those concentrated forces of concussion to which the carpus is so generally liable. * Though this muscle be not attached to any bone, it seem* to perform an office somewhat similar tp that of the traiuwnits 40$ MOTIONS OF THE SECT. VII. MOTIONS OF THE BONES COMPOSING THE METACARPUS, 1 HE metacarpus consists of five bones articulated with the distal row of the carpus, and employed to support the digital phalanxes of the thumb and the fingers. They are generally considered as forming a group like the preceding, and it must be acknowledged that the four of the group be- longing to the fingers have but very little motion as distinct parts ; for although it be true, that the radialis internus and the radialis cxternus longior are inserted into one of them, the radialis externus bre- t vior into another, and the ulnaris externus into a third ; yet they seem to be inserted, not so much with a view to produce any separate effect, as to move the whole at the same time, to support the carpus, and afterwards to inflect it upon the radi- us : the most obvious motion perceived in any of them is in that appropriated to the little finger ; it is perceptibly moved by a muscle called its adduc- tor ; a muscle which prevents it from being too widely separated from the rest, and which draws it a little radiad and thenad. The other motions observed in these bones, and not accompanied with the motions of the carpus, seem chiefly to arise from the action of the muscles that are attached to ATLANTA! EXTREMITIES, 407 the digital phalanxes ; muscles which not only in Home measure regulate the form of this part of the metacarpus according to the nature of the func- tions performed, but also contribute to preserve its parts, as they did the several bones of the car- pus, in their relative positions, though not with such a force as to suppress the freedom of the joints, or that elastic flexibility of the ligaments, so necessary in preventing the dangers arising from the concentrated forces of concussion. The metacarpal bone of the thumb exhibits in its functions a more striking resemblance to the bones constituting the proximal phalanx of the four fingers, than to any of the bones with which it is classed ; it is placed with its two digital pha- lanxes at some distance from the rest of the group; by which situation some of the muscles are made to enter the thumb less obliquely, and consequently to increase the lever of the power, while the want of a bone corresponding to the medial phalanx of the fingers shortens the thumb, and thereby diminish- es the lever of resistance, SECT. VIIL MOTIONS OF THE SEVERAL DIGITAL PHALANXES. ft treating of the motions of the thumb and the fingers, a general observation may here be pre- 408 MOTIONS OF THE mised, that while distal phalanxes must necessa- rily accompany the motions of the medial, and thq medial the motions of the proximal phalanxes, yet muscles inserted into distal phalanxes may be made, if required, to co-operate with the muscles of the same aspect that move the medial, and the muscles of the medial, in the same way, to co-ope- rate with the musfcles of the proximal phalanxes ; whence, proximal phalanxes, independent of the shorter levers of resistance, may, in certain direc- tions, be always inflected with a greater force than medial phalanxes, and medial phalanxes, with a greater force than those w 7 hich are distal. MOTIONS OF THE THUMB, These motions are usually Assigned to eight muscles : The Abductor longus pollicis^, Opponens pollicis*, Abductor brevis pollicisf , Adductor pollicisf, Extensor minor pollicisf. Flexor brevis pollicisf, Extensor major pollicis-f:, Flexor longus pollicis*. The two first, with the abductor indicis manus, which should have been added to this number. * Sec p. 194. f See P' I 97- ATLANTA! EXTREMITIES* being inserted into the metacarp ; the next four, 'into the proximal ; and the two last, into the dis- tal phalanxes. MOTIONS or THE METACARP. yhe motions of the metacarp by its own mus* cles, are Radiad, Thenad, - by the abductor longus; Thenad, Ulnad, and Ulnad rotatory, by the opponens pollicis; Thenad, Ulnad, by the abductor indicis. The motions of the metacarp and phalanx by the muscles of the latter, Thenad, Ulnad, by the abductor brevis ; Ulnad, Anconad, by the adductorj Ulnad, Anconad, by the flexor brevis 5 MOTIONS OF THE Anconad, Radiad, by the extensor minor. MOTIONS OF THE PROXIMAL PHALANX. The motions of this phalanx, which are not ne- cessarily extended to the metacarp, are^m'ofl and extension, with a slight inflection to the radial and idnar aspects of the thumb. The flexion is performed by the Abductor brcvis, Flexor brevis, Adductor. The extension, by the Extensor minor, and Extensor major ; assisted by ihefaxor brevis and the abductor bre- iris, which join them by lateral tendinous expan- sions. The inflection radiad, by the abductor brevis and that portion of the flexor brevis inserted into the radial side of the phalanx. The infection ulnad, by the extensor major and that portion of the flexor brevis inserted into the ulnar side of the phalanx. The motions of the njetacarp and proximal pha- lanx, by musdes inserted into the distal phalanx, are Anconadj Ulnad, "by the extensor major ; A.TLANTAL EXTREMITIES, Ulnad, Thenad, by the flexor longus. MOTIONS OF THE DISTAL PHALANX. The motions of the distal phalanx, not necessari- ly extended to the proximal phalanx, or to the meta- carp, are entirely confined to extension and flexion. Frpm the view here given of the motions of the metacarp, it may readily be seen how the whole thumb may, as well as the humerus, be made to turn round by successive inflections, beginning, suppose, at the radial aspect, and then passing suc- cessively from aspect to aspect till it come to the racjial aspect again. SECT. X. MOTIONS OF THE BONES CONSTITUTING THE THREE PHALANXES OF THE FINGERS. JL HESE motions are performed by the Extensor communis digitorum * t Indicator *, * See p. 198. 4X3 MOTIONS or THE Extensor proprius auricularis, icix minimi digit! f , Abductor minimi digiti f, Flexor parvus minimi digiti f> Abductor iadicis f , Sublimis *, Profundus f , Lumbricales *, Interossei *. MOTIONS or THE BONES OF THE PROXIMAL PHALANX. THESX motions are, Anconad, Thenad, Radiad, Ulnad ; or motions in the intermediate directions. The motion anconad is generally called extension ; the motion thenad is what is called faxion ; while the two motions radiad and ulnad are those by which the fingers recede and approach one another. MOTION ANCONAD. THIS is performed by the tendons of the exten- sor communis, assisted in the index by the indica- tor, and in the little finger by the extensor propri- vs auricularis, sen minimi digiti. When the whole sf the communis is made to act at the same time, f P. 199. * Seep, 198. ATLANTAL EXTREMITIES, the several fingers are seen to diverge like radii from a centre, the index pointing distad and radi- ad, the ring and little finger distad and ulnad. From the lateral connections, however, observed between the tendons of -the communis, it is inca- pable of extending completely a separate finger j the separate extension of the index and little fin- ger being produced by the indicator and extensor proprius auricularis* ; the indicator moving its fin- ger a little ulnad, and in this function moderating the tendon of the communis. MOTION THENAB. THIS is performed by the Lumbricales, Interossei, Sublimis, Profundus, assisted in the index by its abductor, and in the little finger by its flexor brews, and by its abduc- tor. From the lurribricales being inserted along with the tendons of the radial interossei, they are als* disposed to move the fingers radiad. The interossei, from running on the radial and talnar sides, and very little thenad of the centre of * Sometimes wanting. 414 MtfTIONS Ot motion, enjoy but a very limited power as to the flex- ion ; while, from their connection with the tendons of the extensor communis, they seem to co-operate in extending the medial and distal phalanxes. In the same way the lumbricales, which during extension appear to assist the radial interossei, may during flexion assist the tendons of the profundus, and these tendons again assist the lumbricales, just as we see the carneous fibres by their lateral attach- ments shorten the tendons of penniform muscles. The sublimis and profundus, in performing their flexions, make the fingers to approach both from the radial and the ulnar aspects towards the middle, moderating here the extensor communis with some of the interossei and lumbricales ; and' hence during flexion the fingers can never be se- parated so widely as during extension. MOTIONS RADIAD AND ULNAD. THESE are performed by the interossei, which are named external or internal, according as they arise from the anconal or thenal aspect of the meta- carpus; and, prior QI posterior also by Albinus, ac- cording as they are inserted into the radial or ul- nar aspects of the fingers. In these motions the radial interosseus of the index is assisted by the abductor indicis, and the place of ulnar interosse- us in the little finger supplied by the abductor minimi digitl. ATLANTA! EXTREMITIES. 415 From muscles thus acting on the four aspects of each of the bones of the proximal phalanx, it must be evident that each of these bones may be turned round by successive inflections, so as to describe the circumference of a cone, though not turned round as in rotatory motions, which require that the muscles entering the bone should form with its axis less acute angles than are formed by the muscles of this digital phalanx. MEDIAL PHALANX. The motions of the bones of the medial phalanx on those of the proximal are Extension, and Flexion. The extension performed by the same muscles that extended the bones of the proximal phalanx ; assisted, however, in extending the medial and the distal phalanxes by the interossei and the lumbri- coles i and in the little finger by ite flexor and ab- ductor. \ DISTAL PHALANX. The motions of the bones of the distal phalanx, on those of the medial, consist likewise of extension and flexion ; the extension performed by the same muscles as in the medial phalanx, and the flexion, by the tendons of the profundus. MOTIONS OF Although in these motions of the digital pha- lanxes the young anatomist may not be surprised at the extension of all the three by the same mus- cle, yet he certainly has some reason to wonder' how it can maintain the extension of some, and, permit at the same time the flexion of others ; and, more particularly, how proximal joints, rendered convex anconad * by means of flexion, should not stretch its tendons, and compel it to act with a greater force in extending those that are situated distad. To explain these phenomena, it may be remarked, that every phalanx has its own flexors ; and that although the power of extension, however different the levers of resistance, be equal or nearly equal in all, the power of flexion may be different in each. As for the effects of convexity in the joints, it must be remembered that the stretching and relaxing of the tendons, as in many other cases, depend not entirely on the carneous fibres, but on changes of position ; that the tendons of the extensor may be stretched and relaxed at the proximal joint by the convergence and diver- gence of the fingers: and if that be not permitted at the medial joint, yet there we have another me- chanical contrivance, equally and admirably suited to the purpose ; there each of the tendons may be observed dividing into two, the halves passing la*- * See page 29;, ATLAOTAL EXTREMITIES. 417 terally* to avoid the convexity, but uniting again, and leaving a rhomboidal space in the middle; By this simple mechanism the flexion of the me- dial joint does not prevent the flexion of the distal, although it is true that the power of extension would afterwards be less, from the laxity occasion-* ed by the lateral separation, were not the lum- bricaks and the interossei at all times ready, and at all times prompted to give their assistance. SUMMARY REMAR&. ALTHOUGH we cannot pretend to have seen, nor indeed to have explained, if we had seen, all the Singular effects of mechanism in this singular or- gan, the atlantal extremity; yet, from what we have seen, with regard to its motions, that can be explained ; with regard to the promptness, preci- sion, and ease, and the almost incalculable variety of modes in which they may be combined and se- parated ; performed with different degrees of force, velocity, extent, and in every conceivable order of succession from reflecting on the aggregate number of motions in both the extremities, which naturally co-operate ; recollecting that the thumbs and each of the fingers is separately endowed with the sense of touch, and that these, exclusively of their own motions, which are capable of com- bining in thousands of ways, may likewise parti- cipate in the motions of the trunk and sacral extre- D d 418 MOTIONS OF THE mities, in th motions of the clavicles, scapula?, humeri, carpi, and metacarpi we certainly must acknowledge the atlantal extremities to be admi- rably suited to the human intellect ; that the power to plan, and the power to execute, have here been bestowed with a view to each other ; and that it is certainly as much to the one as it is to the other, that man is indebted for most of the- comforts and con- veniences of life ; for sciences, arts, commerce, manufactures ; and, in short, for that distinguished pre-eminence over every other species of anima- ted being that visibly inhabits this terrestrial" globe. CHAP. VI. MOTIONS OF THE SACRAL EXTREMITIES, JL HE sacral extremities seem to have engaged rftore of the attention of physiologists than the at- lantal. The attitudes of standing, with the motions of walking, running, and leaping, being thought subjects fit to receive illustration from the appli- cation of mechanical principles, many authors have SACRAL EXTREMITIES. 4*9 gratuitously offered their services in anatomy, and, satisfied with partial or limited views, have under- taken to explain mechanically the manner in which these phenomena are produced. To facilitate the application of their reasoning, they have generally proceeded on the supposition, that the animal ma* chine is more restricted in its operations than it actually is; hate dwelt much upon the effects ari- sing from form, position, and magnitude ; from the force of gravity, elasticity, and impulse ; and but little upon those arising frofn the agency of the vi- tal principle, without which th animal machine would have presented but few phenomena interest- ing or curious. It is thus "we can account for the differences observed between their conclusions; succeeding authors accusing those who prece- ded them of errors, and boasting, not only of the truth and accuracy, but also of the novelty of their own observations. Had they commenced their several inquiries with more deliberate and exten- sive views, the anatomist must be convinced that they would have differed less as to the explanation of the manner in which standing, walking, running, and leaping are performed by animals, than 1 they seem to have done. Every one knows, or easily may know, that the manner admits of a very considerable range of variety ; thai; the equipoise, whether stand- ing or moving, is not merely committed to the sa- cral extremities, but is shared by all the parts of the system ; and that their different attitudes and 42 MOTIONS OF THE motions, the particular positions of the centre of gravity, the form of the body, and the will itself, have all certain mutual relations, that may be, and that are .regularly varied in a thousand ways by occasion and circumstance. It is hence that some attitudes and motions peculiarly combined distin- guish the vagi, or the in-kneed; some the vari, or the bandy-legged ; that some are made to indicate species of exercise and sport ; some the particular qualities of the ground or its substitutes at the time, as these are smooth, slippery, unequal, broad, narrow, moveable, or fixed ; some, again, the dif- ferent states of health and disease ; and some the different emotions and passions. Now, in all these varieties of attitude and motion, as the position of the centre of gravity must necessarily correspond, it is surely inconsiderate to talk of any attitude or motion by which that position is to be always and uniformly regulated. In tracing the prints of an animal's feet on the snow or the sand, we find that those of the dog, the hare, and the horse when he walks, are in zigzag lines ; and that those of the cat,, of the fox, and the horse when he is galloping at full speed, are usually in straight, or in nearly straight lines. And thus, I am told, can sports- men frequently, from these impressions, and very often independent of their form, not only guess the species of animal, but also the velocity with which it was moving at the time the several marks were imprinted. SACRAL EXTREMITIES. Without appealing, then, to effects that have been ascribed to the influence of demons ; effects that are known occasionally to occur in hysteria, madness, and in the penances of eastern devotees, where motions, accompanied with vigorous exer- tions, are continued for periods that to almost any but ocular witnesses would appear incredible, and where attitudes, naturally fatiguing and painful, are persevered in for numbers of years without in- terruption the motions and attitudes, and the ways of equipoising the body, not only on the feet, but the head and the hands, and in a variety of singu- lar circumstances, as practised by vaulters, dan- cers on ropes, and by those who exhibit singular feats of agility in horsemanship, are of themselves proofs incontestable, that the combinations of atti- tude, and motion, and equilibration, in the human body, are next to incalculable, and that new com- binations might still be produced by further at- tempts, by practice, and study. Such phenomena should instruct us to be cautious as to the grounds on which we presume to limit the powers of the animal structure when under the influence of its vital principle ; and even with respect to inferior animals, should warn us not to conclude too hastily from general appearances, that this or that animal cannot exhibit this or the other attitude and mo- tion. Before we venture to make such assertions, we should first inquire, whether the animal was ver inclined, ever compelled, ever instructed, or 422 MOTIONS OF THE was ever capable of being instructed, to make the attempt ? or, if the attempt had been made, and had failed, still we should inquire, how far habit might have restricted the actions of its muscles ? how far fear, naturally accompanied by peculiar attitudes, might have interfered ? how far the at- tention had been excited ? and, more particularly, how far the object of the experiment had been rightly conceived ? seeing every variety of atti- tude and motion must partly depend on that power by which the muscular functions are directed, and that that power, whether intelligent from instinct or otherwise, must always, in order to prepare the muscles, whether for motion, attitude, or equi- poise, have some previous knowledge of the cir- cumstances to which it is accommodating the actions of its organs. From the want of suh knowledge, the blind, the dizzy, and the intoxicated, are con- stantly in danger of losing their balance ; and the two last, in many an instance, not capable either of standing or walking upon level ground. Had physiologists previously taken these general views, many disputes about the manner in which some of the ordinary motions are performed had ne- ver occurred. The dispute, for instance, whether in walking the pressure be removed from the heads of the femora by the alternate inclinations of the trunk, or by a sort of projectile impulse from the femora below, is one of those that have originated SACRAL EXTREMITIES. 423 HI partial views. To remove the pressure by the alternate inclinations of the trunk, is undoubtedly .the mode that is in general the least fatiguing, the most usually adopted, and perhaps the most grace- ful ; but, taken alone, it is not sufficient in ascend- ing a stair, in hopping or running ; nor is it adopt- ed by some, who are awkward and hobbling in their gait, even when walking in ordinary cases upon level ground. Another dispute, and which has arisen from similar views, is, whether the feet, when brought alternately forward in walking, be made to move in parallel lines, or in lines that are curved dextrad and sinistrad ? and if in the cur- ved, whether the curves, in this way } / , be convex tibiad, or, in this way ( } , convex fibulad? The truth is, they may, if we choose, be made to move in lines that are parallel, although, to preserve the la- teral range of the centre of gravity between the points from which they set out and in which they terminate, and also to diminish, while in their pro- gress the alternate and lateral inclinations of the trunk, they generally are moved in lines that are convex tibiad: the lines that have their convexity fbulad being usually reserved for those cases where the space is limited towards right and left, and where the feet are obliged to cross, in order to terminate in the same straight line ; or for those cases where the joints are rigid, or when the muscles, as MOTIONS OF THE in hemiplegia, can with difficulty perform their flexion, and extensions. These marks, j ( (\ being intended chiefly to illustrate what was meant by convex tibiad and con- vex fibulad, they are not to be considered as de- scriptive of the lines which the feet observe in the motions of walking. To form some idea of these lines, it must be recollected, that on quitting the ground the feet are moved forwards and upwards, then forwards and downwards ; and that their mo- tions in these directions may be, and are very of- ten, combined with those of rotation, adduction, and abduction. To think of exhibiting such lines upon paper, or to think of ascertaining their inde- finite course from merely the impressions that are made upon the ground, would be but an idle and puerile conceit. If the impressions from the feet of a person who has been walking regularly for- wards be carefully examined, it will generally be seen that they are bounded by parallel lines, sup- posed drawn so as to touch the outmost extremities of the lateral points ; that the impressions of each foot are bounded respectively by similar lines; and that all the impressions of the same foot, from the heel to the toes, are themselves parallel. Such impressions, are certainly not calculated to furnish criteria by which we may judge of the varied and indefinite motions of the foot when it is raised, and when it is employed with the head and the neck, trunk and the hands, to form a sort of transient SACRAL EXTREMITIES . 425 equipoise on the proximal head of the opposite fe- mur. When a man is standing, and with equal pres- sure upon both legs, the centre of gravity will be in the middle ; if the pressure be unequal, it will be found towards that side where the pressure is greatest ; if he stand entirely upon one leg, it will fall within the base of the foot on which he is sup- ported ; if he walk or run, it will constantly be shifting between right and left, and always incli- ning from that part where the one foot touches the ground to that part where the other foot is to touch in its turn. If he be afraid of falling to, a side, the range of this centre will be increased dextrad and sinistrad; and sternad and dorsad, if afraid of fall- ing either backwards or forwards : if he run with- out fear, the lateral range will be somewhat dimi- nished ; or if he be more than usually anxious to preserve his balance, both the ranges will be aug- mented. The efforts in leaping will be best ex- plained by that figure which already has been gi- ven*; although in the figure the centre of gravity, contrary to that which actually happens, be sup- posed to fall towards the heel: this supposition, with the other respecting the rigidity of the spine, having been adopted, as they did not materially affect the illustration, in order to render the figure less complex. See p. 291. 426 MOTIONS OF THJC From these accounts of our attitudes and mo- tions, of which in general so great a share has been ascribed to the sacral extremities, we shall now proceed to give some account of the muscu- lar functions of these extremities ; and observe here, on purpose to save unnecessary repetition, that in walking and running, most of their muscles are peculiarly circumstanced, in having their pla- ces of opposite attachment alternately the move- able and fixed points : In both of which cases the directions of their actions may be inferred from the functions ascribed to them. The motions peculiar to the sacral extremity consist of the different motions of the femur, tarsus, the metatarsus, and digital phalanxes. SECT. I. MOTJONS OF THE FEMUR* L HE motions of the femur are those of Extension, Flexion, Abduction, Adduction, Rotation. Of these motions, Extension, carrying the femur dorsad; Flexion, sternad ; SACRAL EXTREMITIES. Abduction, laterad j Adduction, mesiad ; and Rotation turning it round on its axis in two direc- tions ; and, therefore, either rotation fibulad or rotation tibiad, as it turns the toes outwards or inwards. The muscles employed to perform these motions 1 , are the Tensor vaginas femoris*, Gluteus magnus*, medius *, minor *, Pyriformis *, Gemini *, Obturator internus *, Quadratus femoris * t Sartorius f, Gracilis f , Semitendinosus -|-, Semimembranosus f , Biceps cruris f , Rectus cruris f, Adductor brevis femoris *, longus femoris *, magnus femoris *, Psoas magnus *, Iliacus internus *, Obturator externus *. Of which number, the six following, the sartorius, the gracilis, the semitendinosus, the scmimembranosuSi * See p. 202, 203. t See ? 30 4- MOTIONS OF THE the rectus cruris, and the long head of the biceps cruris, are inserted, not Into the femur, but into the leg ; the last being inserted into the fibula, and the other five into the tibia : The rectus cruris, through the medium of the rotula : through which medi- um, the tensor vagina is likewise inserted into the tibia after its attachment in the linea aspera. The extensors are the Gluteus magnus, medius (a part of), minor (doubtful if part of), Pyriformis, Obturator interims, Gemini, Quadratus femoris, Adductor magnus (from the tuberosity of the ischium), Biceps cruris (long head of),J Semitendinosus, Semimembranosus, The flexors are the Sartorius, Gracilis, Tensor vaginae, Pectineus, Adductor longus, brevis, magnus (from the cms of the ischium), lliacus internals^ Psoas magnus, Obturator extermiS| Gluteus minor, SACRAL EXTREMITIES, 429 The abductors are the Tensor vagina, Gluteus magnus > raedius, minor, Pyriformis, Sartorius, Obturator interims, Gemini. The adductors are the Pectineus, Adductor brevis, longus, magnus, Quadratus femoris, Gracilis, Semitendinosus, Semimembranosus, Biceps cruris (long head of)* Obturator externus, Psoas magnus, Iliac us intermis. The rotators fibulad are the Gluteus magnus, medius (part of), minor (doubtful if part Pyriformis, Gemini, Obturator internus, Obturator externus, Quadratus femoris, Iliacui internusi Psoas magnus, 430 MOTIONS OF THE Adductor magnu* longus, brevls, and the Biceps cruris, a little, if the leg -be extended. The rotators tibiad are the Tensor vaginae, Gluteus medius (part of),, Gluteus minorj with the SartoriuSf Gracilis, Semitendinosu^ if the leg be extended. All these muscles, when the femur is fixed, are calculated to produce similar motions likewise on the trunk: the abductor forces inflecting iifbulad; the adductor, tibiad ; the rotatory JSmlad, turning it round by the dorsal aspect ; and the rotatory ti- biad, round by the sternal. Or, if the trunk hap- pen to be moved on the two femora at the same time, the flexor and extensor forces of both will- co-operate with those of their own class ; the ab- ductor forces with the adductor, and the rotatory fibulad with the rotatory tibiad of the opposite fe- mur. From observing here, that some muscles and parts of muscles are flexors and abductors, some abductors and extensors, some extensors and ad- ductors, and some, again, adductors and flexors, it is easy to conceive how the femur, by these, may EXTREMITIES. be made to describe the circumference of a From a muscle, however, or the part of a muscle, being thus employed in different functions, from the great facility with which these different functions are combined, and the small extent to which some of them are carried even in the most favourable positions of the femur, cautions, similar to those recommended in examining the functions of the several muscles belonging to the humerus, become equally necessary here. All these muscles should be examined before the anatomist has destroyed with his knife their relative connections j and then the motions of extension, flexion, abduction, ad- duction, and rotation, should be performed sepa- rately and slowly, and with every possible care and attention, to prevent their combinations, which, if they should happen without being noticed, would lead to very erroneous conclusions. From the joint at the hip admitting of motions si- milar to those produced at the shoulder, and from re- collecting that the femur and pelvis cannot so readi- ly accommodate themselves to one another's motions as the scapula and humerus-, one might at first be in- clined to imagine, from these circumstances, from the varied functions of those numerous muscle^ and the greater forces which they have to exert, that the joint at the hip would be of the two the * See p. 387, 432 MOTIONS OF TKE most frequently luxated. To prevent, however^ such an occurrence, the head of the femur is sunk to the neck in the acetabulum ; while the actions lie re required of the muscles are usually less irre- gular and extensive than those at the shoulder, and consequently less exposed to irregular action. At the same time, in cases of abduction, the head of the femur is pushed to the bottom of the aceta- bulum ; while in adduction, where it points peri- pherad, and towards the margin, it must always re- ceive, though the muscles be unguarded, a proper, though not irresistable, direction from the round- ligament a ligament that is useful, not only by exciting the synovial gland to proportion its secre- tion to the quantity of motion, but which, by ano- ther mechanical contrivance, can afford a security to the motions of the joint that we could not have expected from its physical strength.- The eye, in tracing the line of the femur from the distal towards the proximal extremity, will per- ceive, near the trochanter major, a sudden and ob- vious change of direction. This change of direc- tion removes the femora to a greater distance, en- larges at the pelvis the lateral range of the centre of gravity, alters the course, and diminishes the force of percussion from below, lengthens the lever of ihe different muscles, allows a sufficient space fos their bulk, the genital organs, and the alvine dis- charges, and, lastly, making the change of appear-^ since from the trunk to the femora to be less a~ 3 SACRAL EXTREMITIES. 433 brtlpt, at once contributes to promote the vigour and steadiness of motion, the safety and the gene- ral symmetry of the system. As to the mode of reducing the femur after luxation, it will be sufficient to recommend an at- tention to those circumstances that were former- ly mentioned in treating of the humerus. In attempting this reduction, the functions and force of the rotatory muscles should never be neglected, but strenuously either opposed or assisted by bend- ing the leg, and rolling the femur tibiad orjibulad as the case may require. SECT, II. MOTIONS OF THE TIBIA. 1 HESE are limited to extension and flexion ; and the muscles which perform them are the Rectus cruris *, Vastus interims *, Vastus externus *> ; -Gruralrs *, Tensor vaginae * Glutens magnus f , * JP* 204. f bee p. 20*. EC MOTIONS OF THE Graeilis *, Sartorius *, Semitendinosus*, Semimembranosus *, Biceps cruris f, Gemcllus J, Plantaris f , Bopliteus ** Ihc ex-tensors are the Rectus cruris, Vastus interim*, Vastus externusj, Cruralis, Tensor vaginar, Gluteus magnus> The flexors are the Gracilis, Sartorius, Semitendinosus, Semimembranosus* Biceps cruris, Gemellus, Plantaris, Popliteus, Tensor vagin3% Gluteus magnus. Should it be asked, why the tensor vagina anS glutens magnus are here introduced as muscles of the tibia, and why they are supposed to act not nly as extensors but flexors, the reply is, that See p. 204* f P. 205. P. SACRAL EXTREMITIES. both muscles are evidently tensors of the vagina ; and ihat the vagina, occupying the fibular aspect of the femur, and being continued distad as far as the tibia, is in passing the joint extended rotulad and po^iit^ad of the centre of motion ; whence the two par; .s on different sides of the centre of motion are alternately relaxed and alternately stretched du- ring the extension and flexion of the tibia* The rectus cruris, as a flexor of the femur, is somewhat relaxed when the femur is inflected; and, therefore, often in ascending a hill, or rising with a heavy weight on the shoulders^ we are led instinctively, by a sense of weakness, to press with our hand against the rotular aspect of the femur* and to assist its exertions; to promote which, and to preserve the rectus in its place, the two vasti are inserted laterally into its tendon, while the vastus internus is itself assisted in this operation by the tendon of the adductor magnus, from which several of its fibres originate. The two vasti, proceeding from their origins ro~ tulad and distad, and concealing the cruralis, not only perform the office of a fascia to that muscle, but contribute likewise to support the femur, just as a cord, when closely and spirally twisted on a rod, will add to its strength. Both these muscles, besides their insertion into the rectus, where they form the appearance of a penniform muscle, are inserted laterally into the rotula, and then into the tibia. From this last insertion , they are able, wheji E 436 MOTIONS OF THE the rotula is fractured transversely, to extend the tibia, though with no great force, partly from a deficiency of lever, partly from wanting the assist- ance of the rectus and the cruralis, and partly, too, from wanting the assistance of their own fibres, that are laterally attached to the tendon of the rec- tus. To the two vasti^ the cruralis and fectus, the ro^ tula performs the office of a pulley; it also re- moves them to a greater distance from the centre of motion, and adds to their levers. In resting on the knee, it is better calculated than mere tendon to bear pressure and resist injury, and in its motions requires less of the lubricating fluid. For, had a tendon been substituted, we should naturally sup- pose, judging from analogy, that it would have been surrounded with synovial membrane, like what we see surrounding the tendons at the carpal ligaments. Now, this membrane, with the appa- ratus contained within the capsule, might certainly have added to that frequency of disease to which th.s joint, from its actual apparatus, and its greater ex ient of articular surface, is already more expo- sed than any other joint in the whole system. . The gracilis, the sartorius, and the .semitendinosus, after reaching the tibia, proceed in their course distad and rotulad ; and, in conformity with the biceps brachii and the biceps cruris, transmit each an aponeurosis to support the fasciae, enveloping the muscles of the next articulation. From the SACRAL EYTREMITIES. 437 nature o r tlieir course, they are capable of per- forming a slight degree of rotatory motion upon the tibia when it is inflected ; and in this rotation are partly assisted by the semlmembranosus and the popliteus; while, on the contrary, they are modera- ted by the biceps. It is only, however, in particu- lar circumstances, as when .the functions of ilex- ion and extension are both suspended, that they ever are permitted to roll the tibia. For, when they and the biceps are made to act at the same time in bending the leg, or moderating the exten- sors, that very direction which gave them the power of rotatory motion, is now made the means by w r hich rotation is only the more effectually re- sisted* ; and hence it would appear, that this di- rection was rather intended to prevent rotation when the muscles are employed in vigorous exer- tions, than to promote it when they have no other business to perform. As a farther confirmation of this opinion, the vast us internus and vastus externus, which are made to act at the same time, and are prevented from acting alternately by their attach- ments, must likewise oppose rotatory motion ; in which opposition they will be assisted by the late- ral ligaments, the heads of the gemelius, and in the rotation of the femur fibulad, or the tibia tibiad, by the crucial ligaments' J-. * See page 359. f See page 306. 43$ -MOTIONS OF THE As for their rotatory power on the femur, the case is different ; they are there permitted to act alternately in flexion, extension, adduction, or ab- duction. As the gracitis and sartorius, like the rectus cru- ris, are somewhat relaxed when the femur is inflect- ed, so the long head of the biceps cruris^ with the semitendinosus and the semimembranoms, aie some- what stretched, and in these circumstances enabled to bend the joint of the knee to a greater exient* ; the convexity of the joint operating here in a man- lier that is well explained by Borelli in those pro- positions f , where he proves that the flexion at the joint of the heel must in certain birds, whether dead or alive, be accompanied by the flexion of their digital phalanxes. It is true, indeed, that in these propositions the late Vicq d'Azyr, after show- ing more than usual anxiety to point out some tnyographical errors, and after asserting just what Borelli had asserted before, that one flexor only passes over the convexity at the knee, has, by artfully concealing what Borelli has said of the joint of the heel, and by insinuating what he has not said of the joint of the knee, completely suc- ceeded in convincing Barthez that his cavilling criticism is an able refutation J. But the leg of a *Sec page 296. f De Motu Animalium, Prop. CXLIX, et CL. J " Un phenoraene remarquable de la station des 01 SACRAL EXTREMITIES. i bird that perches in its sleep is easily procured, 'and children, who in general are fond of the experi- ment, can demonstrate the fact which Borelli has explained, and which he has explained by descrip- tions of the muscles, sufficiently minute, and suffi- ciently accurate, to support his conclusions. c'est qu'ils peuvent se soutenir fermement, et meme dormir, ap- puyes sur des branches d'arbre qu'ils embrassent avec les doigti ; de sorte qu'ils ne peuvent en ,tre renverses alors par des coups . Rot dad, 444 MOTIONS OF THE Fibulad, Tibiad, or in some of the intermediate directions; the motion rotulad being what is called Jiexion ; the motion poplitead, what is called extension ; and the two motions fibulad and tibiad^ slight inflec- tions outwards and inwards, that perhaps might be named abduction and adduction. They are so re- lated, that the flexion and extension may be per- formed in any state of abduction or adduction, or adduction and abduction, in any state of nexion or extension. The muscles concerned, are the Tibialis anticus *, Extensor longus d'gitorum *, Extensor proprius pollicis f , Peroneus tcrtiusf, Gemellus J, Soleus f, Plar.'aris ., Flexor longus digitorum *, Flexor longus pollicis f , Tibh.is p(^s icu^ *, Peroneus longus f, Peroneas bievi,- j-. In the motion romlad, the Tibialis anticus, Extensor longus digitorum, Extenso. roprius pollicis t Peroneus tertius : * Vide p. 204. f P. 205. f P. 206. SACRAL EXTREMITIES. 445 In the motion poplitead, the Gemellus, Soleus, Plantaris, Flexor longus digitorum, Flexor longus' pollicis, Tibialis posticus, Peroneus longus, Peroneus brevis : In the motion fibulad, the Ptroneus longus, Peroneus brevis, Peroneus tertius, Extensor longus digitorum : In the motion tibiad, the Tibialis postictts, Extensor proprius, Flexor longus digitorum, Flexor longus pollicis. If besides these, there appear at times to be obvious rotatory motions of the foot, it is to be ob- served, that such motions, though generally com- bined with the two motions fibulad and tibiad, do not properly belong to the joint of the tarsus; they may always and easily be traced to the fe- mur, the tibia, or to both: if the knee be ex- tended, the rotatory motions are to be ascribed en- tirely to the femur; if it be inflected, partly to the tibia ; in which case the rotation of the femur will often be combined with slight degrees of ad- duction and abduction. If the toes, therefore, be seen to point cither 4 MOTIONS OF xite forwards and outwards, or forwards and inwards, we must, in the well-formed sacral extremity, if the knee be extended, look for the causes princi- pally in the femur; its rotators fibulad, consisting of extensors, flexors, abductors, and adductors, are more numerous and more powerful than its rota- tors tibiad ; and whenever, either in standing or walking, a free easy lateral swing is allowed to the trunk, the rotators fibulad, or the abductors, must be brought into action, the toes turned out, or the space between the two feet widened, to enlarge proportionally the lateral range of the centre of gravity. If that range, however, be re- stricted, by checking the lateral inclinations of the trunk, by fear, awkwardness, or any other cir- cumstance, the toes then may be turned inwards ; and if the cause be allowed to operate with fre- quency sufficient to induce habit, a share of the positions, which the parts had in utero for the sake of occupying the least possible space, may in some measure be continued through life. As the gevnellus and the soleus are not the only extensors of the tarsus, why, it may be asked, can- not the tarsus then be extended, though with less force, after the tendo Achillis is ruptured, and particularly if ruptured without any pain ? To answer the question : the gemellus and soleus, strong as they are, would not be sufficient, by a moderate exertion, to raise the weight of the body- on the tarsus without such a lever as the o$ calcis. 3 SACRAL EXTREMITIES. The other muscles, excepting the slender and fee- ble plantaris y have not such a lever. Besides, be- ing destined to perform other functions, and to act here only as auxiliaries, they are not prepared for the change of circumstance, and they want that con- nection with the joint of the knee which is ne- cessary for mutual accommodation in any exer- tion where the two joints are required to co-ope- rate* SECT. V. MOTIONS 1 OF THE SEPARATE BONES QF THE TARSUS, 1 HESE bones, like those of the carpus, admit of little change in relative position, except such a change as enables them to diffuse the concentra- ted forces of pressure and concussion ; and hence the muscles that more immediately act upon one of them have their influence, indirectly extended to the whole. SECT. VI. \ MOTIONS OF THE SEPARATE BONES OF THE METATARSUS. X HE observations on the bones of the tarsus with equal justice, be applied to those composing 448 MOTIONS OF THE the metatarsus ; as no bone here, like the meta- carpal bone of the thumb or the little finger, is found to admit of a separate motion to any ex- tent that is easily perceptible. SECT. VIL MOTIONS OF THE BONES OF THE TARSUS AND METATARSUS. 1 HESE bones, by their forms and arrangements, are made to constitute a general surface that is concave poplitead or plantad, and another surface that is con- vex rotulad. In short, they seem to constitute ar- ches from the proximal to the distal, and from the tibial to the fibular aspects : one arch beginning at the rotular aspect of the os calcis, and thence extending along the astragalus, the os naviculare, the three cuneiform bones, and the three first of the metatarsals ; another commencing at the distal extremity of the os calcis, and thence extending along the cuboides, and the fourth and the fifth of the metatarsals ; and a third extending from right to left, formed at one part by the five metatarsals, and at another by the os cuboides and the three cuneiform bones : The parts constituting these three arches being retained in their relative posi- tions, partly by ligaments surrounding the capsules SACRAL EXTREMITIES. 44$ of articulation, and running in a number of diffe- rent directions ; partly by the plantar aponeuro- sis ; partly by strong muscular tendons mutually interwoven, intermixed with the ligaments, and stretching from one bone to another ; and partly* too, by the action of muscles drawing from the distal to the proximal aspect, from one lateral as- pect to another, or from the distal and lateral as- pects to some points that are situated in,' or near the os calcis. For the os calcis being the bone that affords the most general support to the arches, is also the bone from which, or its neighbourhood, most of the muscles connected with the arches proceed to their insertion. This bone furnishes an origin wholly, or in part, to the Extensor brevis digitorum* Flexor brevis digitorum, Flexor accessorius, seu massa carriea Jacobi Sylvii, Flexor brevis pollicis, Adductor pollicis s Abductor pollicis, Abductor minimi digiti J while \htflexor longus digitorum pedis and \htfexor longus pollicis pedis, by uniting and crossing where they happen to meet with the flexor accessory- us, constitute a central point of their own, near to the place where the preceding muscles origi- nate ; and thence, with these and the four fatr'ri- cales, radiate also in different directions to the di- gital phalanxes : The tmnsversus pedis, in the Ff 450 MOTIONS OF THE meanwhile, giving its support by crossing directly from side to side ; the adductor pollicis and peronem hngus by crossing obliquely ; and the common ex- tensors on the rotular aspect, like the common flexors on the popliteal, by radiating each from contiguous centres, by crossing in their course, and by drawing their insertions, like most of the o- ther muscles of the foot, to points that are either situated in or near the os calcis. The arches of the foot being thus constructed, and more or less, according to circumstances, vi- gorously supported by the action of muscles, are not only calculated to afford a safe and general protection to the muscles, the nerves, the sangui- ferous vessels, and the absorbents on the plantar aspect; but by their elasticity, and the number of the parts of which they are composed, are admi- rably fitted to diffuse the effects of concentrated forces, whether they proceed from above or be- low ; to accommodate themselves in some mea- sure to the forms of the objects which are brought into contact ; and to add to that springy or elastic motion which contributes so much to lessen fa- tigue in walking and running. SACRAL EXTREMITIES, 451 SECT. VI. MOTIONS OF THE BONES OF THE DIGITAL PHALANXES, OF THE DIGITAL PHALANXES OF THE FIRST, OR GREAT TOE. X HESE phalanxes, like those of the thumb, are li* anited to two, a proximal and a distal. PROXIMAL PHALANX. The motions of the proximal phalanx Rotulad, Poplitead, Fibulad, Tibiad, or combinations of these motions ; And are performed by the Extensor brevis digitorum * t Extensor proprius pollicis *, Flexor brevis pollicis *, Flexor longus pollicis *, Abductor pollicis *, Adductor pollicis *, Transversus pedis * : The tnotion rotulad, by a tendon of the Extensor brevis digitorum, and by * P. 21*, 213- MOTIONS tfT THE Extensor proprius pollicitr The motion poplitead, by the Flexor brevis pollicis, Flexor longus pollicia, Abductor pollicis r Adductor pollicis, The motion fibulad, by the Adductor pollicis, Transrersus pedis : The motion tibiad,. by the Abductor pollicis. DISTAL PHALANX. The motions of the distal phalanx arey Extension, and Flexion : The first performed by the Extensor proprius ;. The second, by the Flexor longus* The metatarsal bone of this toe, unlike the me- tacarpal bone of the thumb, admits of nearly as little motion as the other bones with which it is classed. MOTIONS OF THE BONES CONSTITUTING THE PROX- IMAL, MEDIAL, AND BISTAL PHALANXES OF THE* SMALL TOES. PROXIMAL PHALANX. THE motions of the booes of the proximal pha- lanx are, SACRAL EXTREMITIES. Rotulad, Poplitead, Fibulad, Tibiad, j0r combinations of these motions ; And are performed by the Extensor longus digitorum *, Extensor brevis digitorum *, Lumbricales *, Flexor brevis, seu sublimis *, Flexor longus, eu profundus *, Interossei *, Flexor brevis minimi digiti *, Abductor minimi digiti * ; The motion rotulad, or what is called extension, by the Extensor longus digitorum, and Extensor brevis digitorum (the fifth toe ex- cepted) : The motion poplitead or plantad, commonly call- ed flexion, by the JLumbricales, Interossei, Flexor brevis, seu sublimis, Flexor longus, seu profundus, Assisted in the fifth toe by the Flexor brevis minimi Digiti, and Abductor minimi digiti : Thp motion fibulad, by the Fibular interossei ; ID the fifth toe, by the Abductor minimi digiti : * Vide p. 214, 215. 454 MOTIONS OF TH The motion tibiad, by the Tibial interossef, MEDIAL PHALANX. THE motions of the bones of tjie medial pha* lanx are, Extension, and Flexion j The first performed by the Extensor longus, and Extensor brevis (the fifth toe excepted) 5 Occasionally assisted by the Lumbricalea, and Interossei * : The second, by the Flexor brevis, seu sublimis. Flexor longus, seu profundus. DISTAL PHALANX. THE motions of the bones of the distal phalanx B like those of the medial, are also confined to Extension, and Flexion : The first performed by the same muscles that per- formed the extension of the medial phalanx ; the second by the^^or longus digitorum. * Vide p. 414* SACRAL EXTREMITIES. 455 GENERAL REMARKS. THOUGH the sacral extremities do not derive so free and extensive motions from the trunk as the atlantal ; though they do not participate in mo- tions corresponding to those of the two clavicles and scapulae ; though their fibula be fixed with respect to the tibiae ; though their (digital pha- lanxes be comparatively short, and all their meta- tarsals admit comparatively but of little motion : yet their strength is greater than that of the at- lantal, their obedience to the will equally prompt; and as they communicate to the system at large a quantity of motion greater than what they receive in return, they contribute more to the general health, so far as that is dependent on exercise. In short, the two atlantal extremities perform a great- er share of the functions that characterise the ge- nus and species ; the sacral extremities, a greater share of the common functions essential to life : while both kinds, if viewed with 3 reference to the several offices they are destined to perform, bespeak a degree of wisdom and foresight in the contrivance, which beings of our limited intelli- gence would more prudently admire and adore than attempt thoroughly to comprehend. f 450' ) CHAP. VII. MOTIONS OF THE AURICLE, HE lower animals are frequently observed mo- ving their auricles, and in some measure varying their form, according to the intensity and direc- tion of the different sounds to which they are list- ening. It is even said, that some wandering pre- datory tribes of the human species, who are natu- rally led to look with suspicion on every wood, thicket, ravine, and cavern, which they pass, and to mark with attention every sound that floats in the air by night or by day, are also accustomed to move their auricles in a similar manner. But be that as it may, the individuals of civilized nations, being seldom placed in such situations, seldom make use of the muscles of their auricles ; and hence these muscles, originally slender, and grow- ing daily more so by disuse, rarely produce any obvious effects, and, one or two excepted, rarely exhibit any thing more than the semblances of .muscles. Their names are MOTIONS OF THE AJJR1CLE. Attollens auricula m, Anterior auricula:, Retrahentes auriculx, Tragicus, Antitragicus, Major helicis, Minor helicis, Transversus auriculae. As to their functions, I can add nothing satisfacto- ry or important to what has been observed by the truly estimable and accurate Albinus. In the first Book of his Historia Muscukrum, although he speaks doubtfully of some of them as muscles*, in the third Book he is more decided, and assures us, not only that they are muscles, but that he had obser- ved their effects in himself f. Not pretending to have had such experience, I subjoin his account of their functions in the note . * " Aut veri musculi sunt, aut certc ipsis quam simillimi.*- 1 Lib. i. cap. vi. See also p. 13. of this Work. f " Sequentes auriculae minusculi sunt et praetenuesj veri tamen quorum etiam actiones in nobis observavimus." Lib. iii. cap. xxvi. J " Attollens auriculam sursum trahit auriculam, tenditque il- lam ejus partem cui insertus $ maxime si epdem tempore agant front ales et occlpltales. ** inferior auricula helicis eminentiam illam quas concham distinguit, trahit in priora sursum, ac tendit. 4t Retrahentes auricula concham tendunt, auriculam trahunt fetrorsum, J* J'ra^tcus cam cui incurobit conchse partem deprimit^ fa 458 MOTIONS OF MOTIONS OF THE BONES IN THE TYMPANUM, THE bones in the tympanum are the malleus f incus, the os orbiculare, and stapes ; and the mus- cles destined to move these bones, and through these bones the membrana tympani, are the Externus mallei, Laxator tympani t, Tensor tympani, Stapedius : The three first attached to the malleus, and the last to the stapes, By these muscles, the membra^- qitque planiorem ; superiorem tragi marginem in priora ex- rorsum vertit. " Antltragicus extremum antihelicem deprimit antitragum verr sus : hujus maxime eminentem marginem nonnihil extrorsum in posfeeriora vertit : marginem conchas inter locum unde ipse oritur, atque eum cui insert us, medium premit, incurvat, ut ia concham assurgat, magisque tendatur. 44 Major helicis premit, deprimit, percutit partem earn helicis cui incumbit : illam vero cui insertus, modice deorsum trahit. " Minor helms incisuram helicis, cui affixus, contrahit ; par- temque quam occupat, premit, percutit. '* Transversus auricula contrahit, quod auriculae inter con- cham et antihelicem cum scapha intercedit ; idem, cum con- cha et scapha tendit." ALBINI Historia Musculorum, lib. iv. * Albinus and Haller both speak doubtfully as to the mus- cularity of the laxator tympani; a kind of diffidence more fre- quently to be met with in the more accurate and experienced anatomists than in those who arc less qualified to decide. THE AURICLE. fia tympani is in various ways stretched and relax- ed; the two first opposed to one another seeming to stretch and to relax it in different parts ; at the same time stretching the part beyond the malleus, and relaxing that between the malleus and the place of their origin ; the tensor tympani, on the other hand, seeming to produce a general tension, and the stapedius, by acting on the malleus through the os orbiculare and stapes, a general relaxation*; the whole also seeming to extend their functions to the labyrinth ; for if one or more of the semi- circular canals be laid open, and at the same time filled with water, the water will be seen to flow out during the tension, and to flow back again during the relaxation produced in the membrana tympani by their contractions. In the note be- low, the reader may see an account of their func- tions, as given by Albinus f . * This function of the stapedius was first pointed out to me by an ingenious friend, Mr Alexander Walker. f n xterfiu4 mallei malleum in priora trahit, modiceque porum acousticum versus ; ex quo malleum sequens membrana tympa- ni planior fit, et modice laxior, sed inaequaliter, maxime laxata ilia parte quae a priore parte mallei est. " Laxdtor tympani mallei manubrium trahit retrorsum, simul et sursum, et porum acousticum versus; eoque membranam tym- pani eodem versus trahit, laxat, facitque planiorem. " Tensor tympani mallei manubrium a poro acoustico retrahtt ad oppositam tympani partem, et modice eodem tempore in. priora ; quo fit, ut cum malleura seo^uatur membrana MOTIONS OF TJHE AURICLE. REMARKS. THE auricle, the tympanum, and the bones of the tympanum, are wanting in many genera of animals, and different in many of the genera of animals in which they are found. As to their use, no one has yet pointed out precisely the relations and circumstances to which they are adapted, and far less the more obscure relations and circum- stances to which their numerous varieties refer. In examining the ear, anatomists have bestowed but little attention on its physiology ; they have rather chosen to labour, as it were, for the sake of labour ; they have strained the eye, and pored through the microscope, not merely to discover the general form and structure of the organ, but to mark all its visible minutiae, which they have named, and which they have described with as much solemnity as if their observations were to lead to some mighty discovery ; as if trifles wer$ important because they are true ; or as if they ^ould be raised to something of consequence by |he minuteness of tedious description, or the pom- Intro trahere valeat ac tendere, cavamquc efficere a partc pori acoustici. ' Stapedius capitulum stapidis ad os cavernulae, quo exit ten- do sinis attrahit, eoque ita movet stapidem, ut pars posterior basis ejus in vestibulum auris introcat, prior ab eodcm recedit,^ . flift, Musculorum* lib. iv. MOTIONS, pous parade with which they are announced as matters that have not been heard of before. IN treating of the motions of those parts that de not fall under the previous titles, HEAP, NECK, TRUNK, or EXTREMITIES, I shall begin with the parts most atlamad ; and, with as few exceptions as may be, proceed regularly to describe their mo- tions as they occur in our progress sacrad. CHAP. VII! MOTIONS OF THE CUTIS COVERING PARTS OF THE CRANIUM AND THE FACE. JL HE parts of the cutis covering the face, and thence extending over the glabellar, the coronal, the inial, and the two lateral aspects of the crani- um, seem the only parts of the human integuments* that, independent of the motions of bones, are made to change their relative positions in conse- 3 MOTIONS OF 1 HE CUTIS OF quence of the voluntary actions of muscles ^f. Thd changes are produced by the ORBICULARES PALPEBRARUM *, ORBICULARIS ORIS, Epicranius, dexter et sinister*, Corrug'atores superciliorum *, Levatores palpebrarum superiorum f , Buccinatores J, Zygomatici majores , Zygomatici minores , L.evatores angulorum oris J, JLcvatores labli superioris J, Levatores labii superioris alarumqttc nasi J, Nasales labii superioris J, Depressores labii superioris alarumque nasi J, Depressores angulorum oris ][, Depressores labii inferioris {[, JLevatores menti j|, Compressores narium J. Of these muscles, the principal are the three orbicu- lar es\ all the rest being employed to moderate, assist, or direct them in shutting and opening. If they be shut by general contractions through the whole of their circumference, all their different diameters are shortened, but in different proportions : the parts opposite coronad and basilad being made ^f I have never seen the ears, nor the integuments covering the two lattssimi col/i, moved by the separate and voluntary ac- tion of these muscles. * See p. 168. f F. 173. i P. 172, }? P. I74 J P. 176. E CRANIUM AtfD FACE. 463 to press against one another ; but the parts opposite" dextrad and sinistrad being prevented from reach- ing their centre by their attachments, either to bone, cellular membrane, or moderating muscles. While they are shutting, the moderating muscles, and the cut is around, are drawn toward each as toward a centre ; and while they are opening, by the contractions of the moderating muscles (for sphincter muscles cannot open themselves), the cu- tis is seen receding around in different directions, as it were from a centre to a circumference. ORBICULARES PALPEBRARUM. THESE muscles are most fixed toward the mesial angle of the orbit, to which point their superciliary fibres are drawn and directed by the corrugatores superciliorum. By their forcible contractions, they close the eyelids, and compress the eyeballs ; cause the integuments to descend from the forehead, to ascend from the lips*, an d to advance mesiad from the temples : Their moderators being the epicra- nius, the levatores palpebrarum, the depressores labii superioris\ , and the elastic cellular membrane situated n the temples. When these act, the integuments * Assisted here occasionally by the moderators of the upper HP. f Through the medium of the eutis aad moderators of the upper lip. 464 MOTIONS OF THE CUTIS OF again ascend by the forehead, descend by the cheeks, and return laterad towards the temples; causing thereby the eyelids to open, and the eye- balls to be freed from compression* When the tendinous part' of the epicranius, from the inflammation of cutaneous eruptions, or from other causes, adheres to the periosteum beneath, the hairy scalp becomes fixed in its situ- ation ; and the carneous fibres arising from the transverse occipital ridge, not being able to extend their influence to the cutis of the forehead, the wrinkles increase in depth and in number, and appear at an earlier period of life. When the corrugaiores and orbiculares act habi- tually with a greater force than the epicranius, the eyebrows are seen overhanging the orbits, with ridges and furrows more or less marked on the portion of the cutis which covers the glabella. When the slender fibres of the two orbiculares 9 scattered on the eyelids, and by some denominated musculi ciliares, act independently of the larger fibres that encircle the orbits, they have respec- tively for moderating muscles the levatores palpe- brarum superiorum. That motion of the upper or coronal eyelids, which from its suddenness has be- come proverbial, is the effect of these muscles act- ing alternately. By this motion, the lachrymal fluid is uniformly diffused over the cornea?, both its se- cretion and absorption promoted, the transparency and moisturStOf the corneae preserved, and any THE CRANIUM AND FACE, troublesome refractions of light, from particles of dust or accumulated tears, regularly prevented. When the eyes are shut with a more than usual degree of force, or opened to a greater than usual extent, the larger fibres- incircling the orbits, and their moderators, are brought into action ; and if orie of the eyes be thus shut and opened, and not the other, the lateral halves of the epicranius may 'then be seen to act as distinct muscles. ORBICULARIS ORIS FOUR muscles, The two levatores menti, and The two depressores labii superioris alarumque nasi, cause the coronal and basilar parts of.lhis orbicu- laris to meet, and to press, if necessary, against one another, in the shutting of the mouth ; while the following muscles, as its moderators, and as in- termixed with it at their insertion, draw it from the points within its circumference, open the mouth, enlarge its diameters, and draw the integuments to wards, their origins : Directions of action* Nasales labii superioris, Coronad, mesiad. Levatores labii sup. et alarum nasi, Coronad. Levatores labii superioris, Coronad. Levatores angulorum oris, Coronad, laterad-, Zygomatici majores, Cor. lat. in 'ad. Zygomatici mmores, Cor. lat. iniad* Gg 466 MOTIONS OF THE CUTIS or ^ Directions of action, Buccinatores, Laterad, iniad. Depressores angulorum oris> Laterad, basilad. Dep- essores labii inferioris, Laterad, basilad. The first four muscles, the levatores menti and dc~ pressures labii superioris, may be seen co-operating with the orbicularis when the mouth and cheeks are inflated with air, or when the lips are reflected inwards over the teeth, and again co-operating with its moderators when the lips are reflected der- mad, or outwards. MOTIONS OF THE- NASAL CARTILAGES* PART of the cartilages forming the external ori- fices of the nostrils, as well as their integuments, are observed to change their relative positions by the actions of muscles. These two orifices dilate and contract, and some portions of the cartilages that form them are seen to ascend and descend ft little between the mouth and the ossa nasi. These motions are performed by the Orbicularis oris, Depressores labii superioris alarumque nasi, Nasales labii superioris, Levatores labii superioris alarumque nasi, Compressors narium. The coronal lip being previously fixed by its dc+ pressores and orbicularis, the nasales labii superioris^ if thrown into action, draw the moveablepartof the septum toward the mouth; when the compressors, attached at sue extremity to the depressores* and THE CRANIUM AND FACE, 46? at the other to the ossa nasi, not being able to bring their extremities nearer by contraction, press on the lateral parts of the ake, and force them mesiad ; the same effects in these circumstances- being likewise produced in a similar manner, and from similar causes, by the levatores labn siiperioris alantmque nasi. I have said, in these circumstan- ces ; as the only muscles that regularly cause the two alas to approach the septum, are the depressores the compressors narium, and levatores labii superio- ris alarumque nasi, compressing the alse only when the lip is fixed, but dilating them again when it is moveable ; compressing them more when it is de- pressed, and dilating them more when it is eleva- ted. To understand how the same muscles should thus perform such different functions, suppose two cords tied together on the ridge of the nose, and thence descending on each side over the alse, and attached to their margin either by a piece of adhesive plaster or a blunt hook, yet descending beyond their attachment to the alas as far as the mouth, and there tied again with a second knot; if their extremities at the mouth be moveable, and their other extremities be drawn coronad, or towards the brow, they will relax or corrugate the integu- ments upon the nose, and, by drawing the alae co- Jonad and laterad, will expand the nostrils. On the other hand, if the extremities at the mouth be fixed, or drawn at the same time in an opposite di* rectioH, the alse will neither be raised nor depress* 468 MOTIONS OF THE CUTIS OF ed, but forced mesiad toward the septum, and the two orifices of the nostrils diminished by lateral compression, just as they are by the pressure of the atmosphere, when the air is very suddenly inhaled, and the equilibrium between what is external and what is internal thereby destroyed. GENERAL REMARK. CONSIDERING the extent of dilatation and con- traction of which the orbicularis oris is susceptible ; considering too, that wherever it is moved by its own contractions, the levatores menti, the depresso- res Idbii superioris, or its moderators, the integu- ments around, and to some distance, must always either precede or follow it ; considering also, that the several parts of its circumference may be made to approach and made to recede in different direc- tions, either in the lines of the muscular fibres, or in the diagonals of their different forces, and not only made to approach and recede, but to diffe- rent extents, with different forces, different veloci- ties, and in diagonals as varied as the changes of relative action, the modes of combination, or the orders of succession which twenty- three mus- cles may exhibit ; considering maturely all these circumstances, we can hardly be surprised that the lips should assume, independent of the mo- tions of the basilar maxilla, an- 5 independent of inflations by the breath, an almost incalculable va- THE CRANIUM AND FACE. 46$ riety of forms; and that their muscles, combining their effects with those proceeding from the mus- cles of the nose, the eyes, the .two orbiculares palpe- brarum, and their moderators, should, for every shade of emotion and passion, furnish the counte- nance with means of expression next to inexhaust- ible. CHAP. IX. MOTIONS OF THE EYE . JL HE motions of the eye are, Locomotions Inlad, and Glabellad ; Rotatory motions Coronad, and Basiiad, en axes extending between the mesial and the temporal aspect ; * The words eye, auricle, &c. preceded by the definite ar- ticle the, are generally used as collective nouns, and denote what is plural. MOTIONS OF Rotatory motions Mesiad, and Temporad, on axes extending between the coronal and the basilar aspect ; And rotatory motions Mesiad, and Temporad, on axes extending between the inial and glabellar aspect. The muscles by which these motions are per* formed, are the Situation. Direction of action, Rectus attollens*, Coronal, Iniad. Rectus depressor *, Basilar, Iniad. Rectua adductor f, Mesial, Iniad. Rectus abductor *, Temporal, Iniad. Obliquus superior *, Mes. coronal, Glab. mesiad. Obiiquus inferior f, Temper, basilar, Glab. mesiad. The eye being every where imbedded in fat, except on the aspect where the cornea is situated, the motion iniad can be carried only to the extent in which the adipose substance is compressible. In this motion, the four rectl act together in the double capacity* of motors and directors, and the two obliqui in that of moderators ; the rectus attolr lens resisting for the time the rotatory power of the rectus depressor ; the rectus adductor, the*- 19* ? Sec p. 172, f ? ,THEE. 471 tatory power of the rectus abductor ; and the obli- quits superior, the rotatory power of the obliquus inferior. In the motion giabellad, the two obliqui, resisting one another's rotatory powers, become the motors; and the four recti, moderators and di- rectors. In acting separately, these muscles perform on- ly a rotatory motion, when each of the recti is moderated by the rectus of the opposite aspect, and the one of the two obliqui by the other. In such motions the coronal rectus is made to turn the pupil coronad ; the basilar, basilad ; the mesial, me- siad ; the temporal, temporad ; the obliquus superior, basilad and mesiad ; the obliquus inferior, coronad and temporad : and as none of them can, in its se- parate motion, be moderated by any but its own moderator, it follows, that the four remaining muscles may act as directors ; and that, therefore, the rotation of any one muscle may be variously combined with the rotatory motion of every other muscle, excepting that of its own moderator. When the two obliqui act in succession, and are not restricted by the directing forces of the recti, they each roll the eye on a different ax- is, extending obliquely between the inial and glabellar aspects ; and when the four recti act in succession, the eye is turned round, so as to describe the circumference of a cone, whose base is glabel- fed, and whose apex is pointed to the inial aspect. By its six muscles, the eye, like the needle of 47S MOTIONS OY the mariner's compass pointing to the pole, pre4 serves the same relative position with respect to its object, whether the object be in motion or at rest. And hence it is, that instead of the eye moving in the socket, we sometimes see the socket moving round the eye, and the eye quite still, performing its functions : And hence it is, too, that when the eyes are directed to an object that happens to be moving from right to left, or from left to right, the one eye is seen moving mesiad, and the other tem^. porad, at the same time ; the one eye having for its motor its rectus adductor, and the other for its mo- tor its rectus abductor. The correspondence, there- fore, of the motions in the two eyes is only what arises from their being directed to the same ob- ject it does not depend on what might be called corresponding muscles ; it does not depend on any Connection of the optic nerves in the sella turcica, as the optic nerves send not even the shadow of a branch to the muscles of the eye ; and it does not depend on the rays of light striking parts of the retinas that are similarly situated ; for, when the rays enter the pupils by the right or left, they fall on those parts of the retinae that are respectively inesiad in one eye, and temporad in the other, When the motions of the eyes are too limited for the sphere of vision that may be required, the motions of the head, neck, and trunk, are made to co-operate ; and the centre of motion and the centre of .gravity in the human body frequently THE EYE.! 473 coinciding, these several parts can be turned round with such a rapidity dorsad, sternad, dextrad, and sinistrad, that the visible canopy above and be- low, with the earth, that seems bounded by the horizon, may in every direction be viewed in a portion 'of time so minute, that what is successive appears instantaneous. In the lower animals, where gravity acts perpendicular to the plane in which the axis of the body is situated, Nature, which is always fertile in expedient^, has recourse, if ex- tensive vision, be required, to other contrivances of different kinds. In some, where the two flexions of the trunk dextrad and sinistrad are compara- ' lively 'slow, the eyes are placed on the two lateral parts of the head, and assisted by the flexions and rotations of the neck : In some, where the mo-- tions of the neck are wanting or very imperfect; we observe the eyes, on moveable pedicles, pro- jecting from the surface, as in crabs and lobsters : In some, again, where the eyes themselves arc destitute of motion, their number is increased, and eyes are scattered either on the different aspects of the head, as they are in spiders ; or collected to- gether in vast quantities in the two lateral parts of the head, forming convex surfaces, with aspects pointing atlantad, sacrad, sternad, dorsad, dextrad, and sinistrad, as in the libellulce, and a variety of winged insects : In short, the eyes, with respect to motion, situation, and number, have a reference to the form and structure of the animal ; as these, 4 474. MOTIONS or again, have a reference in their turn to variouf functions, relations, and circumstances, which the animal more accurately discovers by instinct, thai* the physiologist by his profound and laborious re- searches. Some have imagine /! that the muscles of the eye vary its form, and accommodate its vision to different degrees of magnitude and distance, of which some vague and general information is previously communicated by impressions on the retina. That animals judge of magnitude and distance partly by the eye, and antecedent to any experience by the sense of touch, is not impro- bable, from the birds and quadrupeds that walk and run, from the fishes that swim, and the in- sects that fly, immediately after birth. At that period a number of animals seem to distinguish, by the sight alone, not only the relative situations of objects, but the different degrees of magnitude nd distance, as accurately as at any period of their lives ; and that they are instinctively led to these distinctions, merely by the difference of lights and shades, may be fairly presumed from ihe gross mistakes to which they are liable with respect to pictures. From the eye, however, be- ing fitted to convey notions of great magni- tudes and distances by a momentary glance of lights and of shades, and from the touch convey- ing notions of only small magnitudes and distan- ces, and these notions by the repetitions of actual fc'HE El>. 475 contact at successive and measurable periods of time, we may easily conceive, that a person, ac- customed for a number of years to form the no- tions of magnitude arid distance by the sense of touch, would be very much puzzled to reconcile Jhe habits and notions derived from that sense with the first" impressions which he afterwards de- rived from the sense of sight ; and as it is only in consequence of experience, that he can infer, from the sight of an object, what are the impres- sions that it would make on the sense of touch ; or that he can infer, from the touch of an object, what are the impressions that it would make on the sense of sight, it is not surprising that our in- ferences here should be Always fallacious, when- ever our experience is limited or defective. That the human eye varies its form to examine objects of different magnitudes, at different dis- tances, and in different lights, is what probably few will deny ; but that the variation is produced by its straight and oblique muscles, is an opinion not so easily believed. These muscles seem chief- ly intended to roll the pupil in different direc* lions; and therefore, in cases where they are wanting, the eyes, to secure an extent of vision, if an extent of vision be requisite, are multiplied in situation and number. From the great hardness of the tunica seleroti- ca in the eyes of birds, the muscles can produce lip direct change either on the cornea or the hu*. 476 MOTIONS OF mours within ; nor can it be demonstrated that are capable of producing such a change in the eyes either of man or of quadrupeds. In such func- tions they could not be assisted by the motions of the head, the neck, or the trunk ; and their loss to the eyes could not be compensated by an in- crease of number, by varied situation, or by move- able pedicles. If they really produce a change of form in the human eye, they in one respect certainly differ from all other muscles. In most individuals, at an advanced period of life, and in many during their infancy and youth, they per- form their functions with so little effect, that they require the assistance of glasses, from their want of ability to increase or diminish the convexity o the cornea. In the feathered tribes, a ring composed of os- seous plates, and uniting the sclerotic coat and the cornea, is capable of being dilated and contracted by the action of the iris in its dilatation and con- traction of the pupil. By a similar action, the ring formed by the ciliary plicas, where they in- circle the .body of the lens, may also be either di- lated or contracted in the human species. When it is contracted, the axis of the eye, extending from the pupil to the optic nerve, will be some- what elongated ; the part of the humours that hap- pens to be iniad will be pressed more, iniad, and that towards the pupil still more giabelkd, by the tightening of the zone. A contrary effect will THE EYE. 477 be produced when the ring is dilated ; and both effects will have their influence in varying the form of at least one part of the vitreous humour, in affecting slightly the situation of the lens, and in changing the proportion between the anterior and posterior chamber of the aqueous humour. That the pupil is made to dilate and contract in performing certain functions of vision, is what no physiologist has yet denied. The question is only, whether are these changes produced by muscles ; 'by a sphincter, for instance, and its moderators? a question that still remains undecided. The effects here ascribed to the iris have been ascribed by Dr Porterfield to the ciliary plicae. Now the Doctor imagined, not only that these plicoe were muscles, but also that they run from the ciliary ligament towards the lens in an inial direction : A singular opinion for an author of such accuracy, ingenuity, and learning ; as the first hypothesis cannot be demonstrated, and as the second is so totally unfounded, that a cursory inspection of a recent eye is sufficient at any time to prove the contrary. , The iris, however, besides producing changes in form and in situation by its contractions and di- latations, has another office of no less importance : I mean the office of regulating the quantity of light that is admitted, in proportion to the magnitude or distance of the object, the quantity of light re- flected from its surface, or the sensibility of the 473 MOTIONS OF eye at the time. In this office it is assisted by the eyelids and eyelashes ; and so much has been as- cribed to its action in this way, that any other change, to fit the eye for distinct vision at diffe- rent distances, has by some physiologists been thought unnecessary. But, considering the powers by which the eye varies and modifies its sphere of vision, and ren- ders the cornea more or less convex, there is one reflection that must unavoidably occur to every one ; a reflection on that gradual diminution of the cornea's convexity induced by old age : What is the reason that the iris, and muscles pos- sessing apparently all their original functions and powers, cannot obviate this change? Or, when the iris is too convex, as in some individuals du- ring the earlier periods of life, what is the reasori that the iris and muscles cannot lessen the con- vexity so as to render glasses unnecessary in exa- mining the greater magnitudes and distances ? Can this be owing to a change in the quality, or rather to a change in the quantity of the humours ? That it is owing to a change in the quantity, is more than probable, from the flattening of the cor- nea in consequence of age ; a period when the cus- tomary fluids of the body cease to bear that propor- tion to the solids, which they did in the dawn and noonday of life. It is probable, too, from the nature of the glasses that are found to remedy the defects sf ybioo, a'nd probable from the time which the eye THE EtE;- 47f requires to accommodate itself to different lights, magnitudes, and distances. In passing suddenly from darkness to light, or from light to darkness, or in viewing accurately one object after another, at different distances and of different magnitudes, although we be conscious that the eye necessarily undergoes a change, we are conscious also that the transition is gradual and slow, and unlike the usual effects of the muscles. To account for such transitions, we have to recollect, that the eye, in- dependent of any direct muscular action, is made to assume different appearances under the infhu ence of different passions, different appearances ii* different diseases, and even in the different periods of life ; and that, consequently, much of these appearances must always depend on the state of circulation, and on that mutual relation of action between the sanguiferous and absorbent vessels ; a kind of relation that may be varied by emotion and passion, by local irritation, by muscular ac- tion, and by other causes. That the humours of the eye support the cornea, and giye it convexity, is proved from what we regularly observe in ex- tracting the lens. That a little more than the usual quantity of fluid in the vessels, gives always an additional convexity to the cornea, is proved from injecting the ophthalmic veins with water or mercury ; a drop or two of either of these fluids rendering the whole eyeball- haard, and the come^ so tense that it loses its. tEanspaEejQ.y r ands- in palm .480 MOTIONS OF of colour, resembles a mixture of water and rnilk* That the veins of the eye may be more or less dis- tended by the state of circulation, is proved from inflammation : and that the cornea may be more or less distended from a similar cause, is proved by the pain arising from tension, and which is relie- ved by discharging a part of the aqueous homour*} and proved, also, from an opacity that sometimes pervades it in a few hours, and which may occa- sionally, be afterwards removed by bleeding and purging f. That the aqueous humour enters the eye partly at the angle that is formed between the iris and cornea, may be demonstrated by a mercu- rial injection of the veins; whilq that injection .may also show. whether the iris be convex or plane, That the aqueous humour is constantly flowing into its chambers, is probable from that which takes place after death, when the supply not being equal to the expenditure, the cornea collapses, and be- comes dim. That it flows into these chambers in considerable quantity, may be presumed from the shortness of the time in which it fills not only the places destined for itself, but the places of the lens and the vitreous humour, after these are dis- charged. That the action of the muscles which * See a paper of Mr Wardrop's in the Edinburgh Medical and Surgical Journal, No. IX. f See Dr Edmonston on Ophthalmia, p. 173* THE YEi 48 1 Surround the vessels upon the peripheral aspect of the eye, may have some effect, though not a direct one, in regulating its influx, and in that way the convexity of the cornea, is not unlikely. For, if the blood return not by the veins as fast as it flows in by the arteries, a greater quantity of that which is transparent will be forced into the vessels that terminate in the cavities and upon the surface. Now the current of the blood returning from the orbit by the veins of the face, being partly retarded by the contraction of the orbicularis palpebrw ; and the currents of the veins, passing through the fora- men lac erum by the contractions of the four recti, it. is probable that these muscles act with a much more than ordinary force, when we are examining minute or near objects, where a greater convexity of the cornea is required, and with very little force, and that too but a moderating force, when we are examining objects at a distance. If in this way they produce not the convexity that may be required, it is because the convexity depends but partly on their action; depending more on the state of circulation, and on that irritability of the system through which the vital principle in- stinctively regulates the functions. Whence, in the later periods of life, when the sensibility of the system is diminished, when the circulation of the fluids is languid, when the supply furnished is less, and the waste greater, the cornea loses a part of its convexity, which no action of the Hh MOTIONS OF THE cles can restore. The like causes may be seen operating on the sexual organs. In the evening of life, the memory may recal, and imagination attempt to revive, those mental emotions, by which they grew turgid, to perform their functions ; but the system then will plead irresistibly, that the time is past ; that the streams of life are but scant- ily supplied ; and that the organs, like the sapless leaves withering in autumn, are hastening to decay. CHAP. X. MOTIONS OF THE BASILAR MAXILLA. 1 HESE motions are, Coronad, Basilad, Antiniad, Iniad, Dextrad, Sinistrad. Coronad and basilad. In motions directly coro- nad and basilad, the condyles move out and into their sockets in lines perpendicular to the base of the cranium. In many animals, where the jaw is hinged in the osseous structure, these motions cannot BASILAR. MAXILLAi 488 fae performed ; nor the two motions antiniad and iniad, nor the two motions dextrad and sinistrad, where the condyles move round a common centre. In the ginglymus motions coronad and basi- lad, employed in the shutting and opening of the mouth, the maxilla is moved upon an axis passing transversely through its two condyles. Or, if the condyles during these motions be moved alternately antiniad and iniad, they are moved upon an axis passing transversely through the necks of the condyles. Antiniad and iniad. In these motions the con- dyles are made to change their situations, not only by moving antiniad and iniad, but also by mo- ving in a slight degree basilad and coronad; basi- lad, when they leave their articular cavities to move antiniad ; and coronad r when they return to their place. Dextrad and sinistrad. In these motions the condyles slide dextrad and sinistrad in lines per- pendicular to the lateral aspects; in which case one of the condyles will be moving mesiad, and the other laterad, at the same time. Or both condyles will move in the segments of concentric circles, described round a centre alter- nately situated in the two rami ; while the planes of the circles will either be parallel, oblique, or perpendicular to the base of the cranium. When parallel or oblique, the centre of motion will be in an axis perpendicular or inclined to Hh2 OF THE the base of the cranium, and more or less remo- ved from the middle part of the condyle towards the coronoid process of the ramus in which the centre of motion is situated. When perpendicular^ the centre of motion will be ipore or less mesiad of the condyle which is near- est the centre, a little basilad towards its cervix, and situated in an axis extending antiniad and iniad in a plane that is parallel to the base of the cranium. This motion, however, must be rare, as few individuals can open the jaw wider at the one side than at the other, and never to any very ob- vious extent. If the two condyles were to move either dex- trad or sinistrad in the circumference of the same circle, and the chin to move in an opposite direc- tion round the same centre, that centre would be equidistant from the two rami, but not farther an- tirxiad than the rami. This motion also, if ever it occur, must occur very seldom : for, when the jaw moves dextrad and sinistrad, and parallel or ob- lique to the base of the cranium, the two condyles move in the segments of concentric circles ; the Qne iniad and mesiad, the other antiniad and late- tad, at the same time, If the centre of motion were to retain a sta- tionary place in one of the condyles, the other condyle would be made to move in the segments of circles, whose planes are parallel, oblique, or perpendicular, to flie. base of the cranium. But 3 BASILAR MAXILLA. 485 from the shape of the condyles and their cavities, and from the attachments of the different muscles, I am not certain that these motions ever tire per- formed, or can be performed. In no case is the centre of motion ever to be found in any part of the basilar maxilla lying be- tween the symphysis and rami, and never conse- quently can either the centre or the axis of mo- rion be placed at a distance from both condyles at the same time. The muscles by which these motions are per- formed, are the Directions of action. Temporales *, Coronad, mesiad, iniad, antiniad 1 );, Masseteres *, Cor. lat. antin. iniad f. Pterygoidei intern! *, Cor. mes. antiniad. Pterygoidei cxterni *, Basilad, mes. antiniad. liatissimi colli *, Bas. lat. iniad. Biventres maxillae *, Bas. lat. iniad. Mylohyoidei *, , Bas. mes. antiniad, Geniohyoidei*, 9 Bas. iniad. Geniohyoglossi *, Bas. iniad. The three last pairs, in order to act with any force on the basilar maxilla, require the os hyoi- des to be fixed or drawn sacrad ; and even then they can move it only iniad and basilad ; the * See p. 176. See note p. 316. f Some fibres of the temporal^ draw coronad and and some of the raasseteres coronal and iniad, t Seep. 317. 486 MOTIONS OF THE mylohyoidei having no power to move it dextrad, .sinistrad, or antiniad ; having no fixed point but the os hyoides, and themselves contributing to fix that point between the two halves of the basilar maxilla, depressing the maxilla through the^-. niohyoidei * , but exerting no force dextrad, sinis- trad, or antiniad, that can be directly or indirect- ly extended over an articulation. The live last pairs, whose directions of action may either be expressed in terms alluding to the aspects of the head or the aspects of the trunk, are all attached at some distance antiniad of the rami ; and though incapable of drawing the con- dyles antiniad or basilad, yet they are able to de- press the chin with considerable force, compensa- ting the want of physical strength by the length of their levers. In all the motions of the basilar maxilla, the coronal forces moderate the basilar ; the antinial, the inial ; the lateral, the lateral ; and the mesial, the mesial of the opposite sides. In all lateral motions, however, the mesial for- ces moderate the lateral of their own side, combi- ning with the lateral of the opposite ; and, vice versa, the lateral forces, combining with the me- sial of the opposite side, moderate the mesial of their own side. * See p. 316. BASILAR MAXILLA. MOTIONS DIRECTLY CORONAD AND BASILAD. IN these motions the coronal forces of the tem- porales, the masseteres, and pterygoidei interni, and the basilar forces of the pterygoidei externi, are al- ternately the motors and moderators ; the anti- nial and inial forces of all the muscles, and the mesial and lateral of all the muscles, excepting those attached at one extremity to 'the os hyoides, being the directors. For obvious reasons, the mo- tion basilad in this case can never be carried to any very perceptible extent without danger ; and hence we find there are no forces which can draw the condyles directly basilad, without the direc- tion of the powerful muscles that draw them co- ronad ; which muscles acting at a small distance from the two condyles, never, unless when taken by surprise, allow the condyles to be moved so far out of their place in the basilar direction as to expose them to the danger of luxation. GINGLYMUS MOTIONS CORONAD AND BASILAD, When the axis passes transversely through the condyles. IN these motions the coronal forces of the tem- porcles, the masseteres, and pterygoidei interni, and the basilar forces of the latissimi colli, the biventres maxilla, the myhhyodei, the geniohyoidei, and genio- MOTIONS OF TMK hyoglossi, are alternately the moderators and mo- tors ; the inial and antinial forces of all the pairs, and the mesial and lateral of all the pairs, except- ing those attached at one extremity to the os hyoi- des, being the directors. When the axis of motion passes transversely through the necks of the condyles. In these motions the mesial and lateral forces only are directors ; the antinial and inial, as well as the coronal and basilar forces, being alternately motors and moderators : the pterygoidei externi drawing the condyles in the opening of the jaw antiniad and basilad; while all the basilar and co- ronal forces that draw toward the inial aspect com- bine in restoring them to their situation. MOTIONS ANTINIAD AND INI AD. The pterygoidei externi are principally concern- pd in the motion antiniad, assisted at the com- mencement of their action by the pterygoidei inter- ni, and by part of the temporales and masseteres, moderated, however, from first to last, by the la- tissimi colli and biventres maxilla; or, if the os hy- oides be a fixed point, by the mylohyoidei, the ge~ niohyoidei, and the geniohyoglossi : the coronal and basilar forces of all the muscles, and the mesial and lateral of all the muscles, excepting those at- tached at one extremity to the os hyoides, being the directors. BASILAR. MAXILtA. 48$ MOTIONS DEXTRAD AND SINISTRAD, Simply dextrad and sinistrad* IN these motions the mesial and lateral forces of all the muscles, excepting those attached at one extremity to the os hyoides, are alternately motors and moderators*,. the other forces being the direc- tors. When the condyles move round a common centre in planes parallel, or nearly parallel, to the base of the cranium. In these motions, as one of the condyles is al r ways moving iniad and raesiacj, while the other is moving antiniad and laterad, the 'inial and antinial forces, with the mesial and lateral, excepting as above, being necessarily either moderators or mo- tors, the only directors will be the coronal * and basilar forces, When the condyles move round a common centre m planes perpendicular to. the base of the cranium. In these motions, the whole mesial and lateral forces, with the previous exceptions, the whole of the coronal forces, and the basilar forces of the two pterygoidei externi, are employed as moderators or motors, the inial and antinial being the directors. * Jioxv they moderate and assist, see p. 486, ( 490 ) CHAP. XI. MOTIONS OF THE TONGUE*, J.HESE motions are, Dextrad, Sinistrad, Antiniad, Iniad, Coronad, Basilad ; motions also by which it is varied in Length, Breadth, and in - Thickness ; and motions by which it is Folded, Coiled, and Inflected in different directions. By the two motions dextrad and smistrad, it is moved alternately from side to side. * In Greejs. yxo and vibratory motion ; that the trachea, through which it passes, may be lengthened, and shortened, increased and diminished in its dia- meter, made more or less tense, and, by the. quan- tity of its circulating fluids, more or less elastic : considering, too, that the ligaments of the glottis, which are naturally elastic, may also at the same time be lengthened or shortened, made more or less :tense, and the aperture between narrowed, widened, or entirely closed : considering that all the cartilages MOTIONS OF THE of the larynx are likewise elastic; that, in whole o in part they admit of changes in relative position; that the orifice of the larynx, between the epiglot- tis and the thyroid cartilage, may admit of some thousand changes of dimension ; that the muscles of the pharynx, of the pendulous velum, the lips, the tongue, and the alae of the nostrils, can produce millions of changes besides; and that all these changes may be produced with a difference of force, and a difference of extent, as instantaneouly as the will or thought, and with a degree of mi- nuteness and accuracy beyond comprehension: considering these things, it is hard to conceive how any person among the followers of Dodart or of Ferrein could, upon cool deliberate reflection, think of comparing this singular aparatus to either a wind or a stringed instrument of their own con- trivance, or dispute for a moment, whether sound be produced by the vibrations of the two ligaments forming the glottis, or without vibrations, merely by the aperture that is formed between them. A slight change in the state of circulation, destroying the natural elasticity of , these organs, is capable of rendering them completely mute, as not unfre- quently happens in catarrh. For all sound, whe- ther from a wind or a stringed instrument, must necessarily be the effect of vibrations, though these vibrations may be greatly varied by varying either the dimensions or actions of the .different cavities, tubes, and apertures through which such vibra- 4 VELUM PENDULUM pilAT J. vl3 ttons are conveyed to the ear*. The air itself, in these cases, must also be considered as a sonorous body, and as, when it strikes the ^Eolian harp, ca- pable both of giving and receiving sonorous vibra- tions as it passes through the different organs of voice. In short, there is no general principle in either a wind or a stringed instrument, that is not to be found in these organs, while these organs have numbers of powers, that no instrument of humaii invention ever has possessed. Independent, there- fore, of their different cavities, tubes, and aper- tures ; independent of their glands, their nerves, their membranes, their ligaments, their arteries, their veins, and their absorbents ; independent of all their numerous varieties, and their consequent modifications of action ; considering merely the: almost infinite number of motions performed by their muscles, varied in extent, force, velocity, in the mode of combination, and order of Succes- sion we must surely be conscious that this system of organs can never be imitated, and far less equal-* led by art ; and need not be surprised, consider- ing the original compass of its powers, unfettered by habits, that it should be able, from varieties of stops, emphases, articulations, and cadences, to * On the varieties of vocal organs in different animals, se Vlcq D'dzyr de POJ$an? de la Vo\x t and Ciivier's work Oii Comparative Anatomy. Kk 514 Siemens or furnish marked vocal distinctions, not only for kingdoms, nations, and languages, but for all the individuals of which they are composed ; for all the individuals that are, that were, or that ever shall be ; for all their sensations, passions, and diseases ; and for every shade of which these are susceptible from age, sex, health, or disease. CHAP. XVL MOTIONS OF RESPIRATION, IN the human body, the great reservoir of air is the lungs, in the two lateral cavities of the thorax. From our first inspiration, at the moment of birth, this reservoir contains always more or less of aeri- al iiuid, and is never exhausted by any expiration that afterwards succeeds ; not even by the last. The air within it is a mixture or compound, con- siderably different from that of the atmosphere ; a compound which, by a mutual interchange be- tween it and the system, and a mutual interchange INSPIRATION; 515 between it and the atmosphere, is constantly was- ted and constantly renewed ; and yet ; with a few occasional varieties, is made to retain nearly the same general properties through all the ordinary occurrences of life. To accommodate the two species of interchange to all the varying func- tions of the system, a greater or less quantity of the compound is always detained in the reser- voir; the inspirations and the expirations that fol- low alternately are more or less equalled in bulk^ succeed one another in a quicker or slower order of succession, are performed with a greater or less force, and a greater or less degree of velocity. The muscles employed in producing these! changes, are those which dilate and contract the thorax. The dilating muscles are the Intercostales, Supracostales, Infracostales, Diaphragma ; Assisted occasionally by the Sternomastoidei, Scaleni, Serrati postici superioress Serrati antici, Serrati magni *, Subclavii, * See p. 381. et Halleri Element. Physiologiae, lib. viii. 51(5 TVTOrriONS OF Feetorales, Latissimi dors!, Cervicales descendentcs, Accessorii ad sacrolumbales *l The contracting muscles are the Triangulates stern i, Obliqui externi abdominis, Obliqui interni abdominis, \ Transversi abdominis, Recti abdominis, Pyramidales ; Assisted occasionally by the Serrati postici iaferibrcij Longissimi dorsi, Sacrolumbales, Quadrati lumborum, Serrati magni 5 and assisted always by the cartilages between the? ribs and the sternum, by the manner in which the different ribs are articulated with the vertebrae, and by the ligaments intended to support the articula- tions; causes that, continuing to operate after death, depress the ribs, when the powers that acted by a vital energy are no longer able to oppose them* As all the ribs are more or less curved, and as, from the middle part of their curvatures, they are all bent both towards the vertebrae and sternum, each will have a dorsal and sternal extremity ; as all are flattened, each will have likewise two sides * When the tacrolumbalcs are fixed atlantad, the acc$ssorii must, by their contractions, draw the ribs to the point that ii fixed. RESPIRATION. g,nd two margins : the sides of the first, beginning to number from the region of the atlas, are atlan- tal and sacral ; thejr two margins, peripheral and central, the peripheral convex, the central con- cave ; the former inclining somewhat sacrad, and the latter atlantad. But as we advance to the re- gion of the sacrum, the sides become peripheral and central, the two margins atlantal and sacral ; yet both the sides and margins respectively point- ing somewhat to the different aspects to which the analogous sides and margins were observed to point in the first rib. All the ribs are divided into pairs. Each pair has a different curvature ; the curvature of the first pair is the greatest, and the curvature of the rest gradually less, to the twelfth pair inclusive. Each pair has a different inclination to the axis of the trunk. The inclination of the first is the least ^ the inclination of the rest is greater, to the twelfth pair inclusive. Each pair has a different length. The length of the first pair is the least ; the length of the rest is gradually increased, to the seventh, or even to the eighth, inclusive, and thence gradually diminish- ed, to the twelfth inclusive. All are articulated with the bodies of the ver- tebrae, and all, excepting the two l^st, with trans- verse processes. Excepting also the first and two last, the individuals of each pair are generally ar- ticulated with two vertebrae, being each connect- ed with the vertebral column opposite an inter- 518 MOTIONS 01? vertebral space ; where, situated near to the cen- tres of motion on which the different vertebrae are moved, they are less exposed to any change of re- lative situation from inflections of the trunk. From their strong connections with the verte- bral column, their relative distances at that part can be very little increased or diminished, with- out either a rupture of the ligaments, a change in the vertebras, or in the intervertebral cartilages. All the pairs, attheir sternal extremity, are pointed with cartilages, and in such a manner, that these cartilages, with respect to form, appear continuations of the ribs themselves. The cartilages of the first pair are the shortest ; the cartilages of the rest are gradually longer, to the seventh inclusive, and then gradually shorter, to the twelfth inclusive. The cartilages of the first pair, to the seventh in- clusive, are connected with the sternum ; and the cartilages of the seventh, to the twelfth inclusive, connected with the diaphragm. All the cartilages point somewhat atlantad ; and of the cartilages articulated with the sternum, those of the first pair are always articulated at the great- est angle, the angles formed by the other cartila- ges being gradully less, or more and more acute on the sacral aspect, to the seventh inclusive. Measuring at the sternum, the distance between the first and second cartilages is always the greatest, and that distance gradually diminished to the se- yenth inclusive ; the eighth' pair of cartilages rests RESPIRATION. upon the seventh, the ninth on the eighth, and the tenth on the ninth; the eleventh recedes a little from the tenth, and the twelfth recedes more from the eleventh. All the pairs of the ribs are moveable, but those which are atlantad less moveable than those which are sacrad. Hence, during the contractions of the intercostales, which are calculated to diminish the costal interstices, all the ribs, in ordinary cases, may be seen to move a little atlantad. In this as- cent, as the distances between them at their dor- sal extremities cannot be diminished, their planes of inclination are changed. In this change of the planes of inclination, the sternum and sternal extremities of the ribs are oTp- serv.ed to move Atlantad and sternad, and the car- tilages of the ribs connected with the sternum to become less curved, and the angles which they form with the sternum sacrad to be somewhat aug- mented. The sternum, however, though it partly move along with the ribs, does, notwithstanding, from its connection with the recti abdominis, and some other muscles, make a considerable degree of resistance ; a degree of resistance which is much increased upon the sternal extremities of the ribs by the elasticity of their own cartilages, and the moderating force of the triangular es. . By these resistances, the cartilages of the ribs connected with the sternum, force their ribs dorsad and laterad ; and these forces resisted by the ver~ *J2G MOTIONS OF tebrae, the ribs are more bent near their dorsal ex* tremity than at any other place. The cartilages, too, which, by entering the sternum at acute an- gles, more powerfully resist the ascent of their ribs, frequently bend the sternal extremities of their ribs sacrad, and more or less according to the degree of resistance which, they had opposed. From this resistance opposed to the ribs at their sternal extremity, and the action of the ligaments Opposing their ascent at the dorsal extremity, the motion of the ribs is most conspicuous on the late- ral aspects. From the form of the thorax tapering atlantad, every rib, when cfrawn to the one immediately at- lantad, is drawn not only atlantad and centrad, but rolled a little upon one or both of its extremi- ties, and in such manner that its margin atlantad is turned a little centrad, and its margin sacrad a little peripherad. From the resistance which is opposed at the sternum and vertebras to the rotatory motion, and the motion atlantad, many of the ribs are found to be twisted ; the twist greatest in the long ribs connected with the sternum, but greater or less in proportion to the extent of the motion near the middle of their curvatures, and to the resistance at their extremities dorsal and sternal. . As all the sternal extremities of the ribs, in their motion atlantad, must advance sternad ; as all the ribs connected with the sternum are forced in thei~ RESPIRATION. 521 gscent dorsad and laterad; and as all the ribs no connected with the sternum do, in ordinary cases, follow a little the motions of the rest, the cavity of the thorax is by these motions not only enlarged, from the sternal to the dorsal, but from the sinis- tral to the dextral aspect. In this enlargement by the inlcrcostqles, the dia- phragm will oppose, with a moderating force, and in all directions, not excepting the atlantal, the motions produced in the seventh, the eighth, and the ninth pair of ribs, to the twelfth inclusive ; al- though, upon the contraction of the diaphragm, if the ribs be more fixed than its cordiform tendon, and they generally are in ordinary cases the cor- diform tendon, drawn sacrad and peripherad upon every side, will be rendered less concave on its sa- cral aspect; the liver, the stomach, the spleen, and the intestines, all pushed before it in a direction to- wards the pelvis ; its atlantal aspect rendered less convex ; the mediastinum in the thorax elongated ; the heart and pericardium both drawn sacrad; the lateral spaces between the diaphragm and cos- tal pleura enlarged ; and a third diameter of the cavity of the thorax, from the atlantal to the sacra) aspect, considerably lengthened. In proportion as this dilatation advances, the air within the Jungs gradually expands, the pulmonic blood flows more copiously through all the ramifi- cations of its artery ; and, likewise, in proportion as the equilibrium between the external and inter-* MOTIONS 05* nal air is in this way destroyed, the fontier is ob- served to rush into the lungs, and by its pressure, not only to assist the force of the blood, and the force of expansion in dilating the lungs, but in supporting the action of the diaphragm and the intercostals. And hence it is, that no person, with his utmost efforts, can dilate the thorax to any very considerable extent without the inspiration of air ; although, even then, the muscles be assisted by the expansive power of the air already in the lungs, and partly by the blood, which, if we may judge from effects produced by injecting the pulmonic artery after death, will, if flowing with force, and in any large quantity, increase the size of the lungs as much as if we had inflated their vesicles with air. When the thorax is dilated, the fibres of the recti and obliqui abdominis are considerably stretched, and their levers elongated *. With these advan- tages, beginning to contract, they draw the ribs sacrad and centrad, press the viscera against 'the diaphragm ; while the diaphragm resisting, thopgh with moderating force, the motion atlantad, pushes before it the heart and pericardium, shortens the length of the mediastinum, and, forced towards the jibs dextrad and sinistrad, diminishes the lateral cavities of the thorax. By these forces, by the contractile power of the lungs, and expansion c-f See page 355. EESPIRATION". 6^3 the air, from heat and vapour, the pressure of the atmosphere is overcome, and a volume of air, pro- portioned to the diminution of capacity in the tho- rax, expelled in expiration. In this contraction, as the lungs are compressed upon every side, and regularly oppose, from the slowness of their action, a kind of resistance to the ribs and the diaphragm, if an opening be made into one of the sidt:s, a portion of the lungs will frequently be seen to protrude through the orifice, or air to rush out, if air has been previously in the lateral cavity. On the other hand, if, after a par- tial collapse of the lungs, the thorax be suddenly and forcibly dilated, by the removal of pressure- from their surface, not only will the air within them expand, but the air from without be seen to rush in, both by the- orifice and the trachea, until the equilibrium be fully restored : or, if the cir- culation be continued unequally, and the blood happen to flow more quickly through the pulmo-^ nic than systemic ventricle, the accumulation of blood in the lungs will cause them to expand, in opposition to the pressure of the atmosphere thro* the lateral orifice. These phenomena have some- times led physiologists to suppose, that the lungs possess a muscular power of expanding themselves, and that they expand exactly at the time when the thorax is contracting. But never have I seen the air flowing out by the trachea, while flowing in by the lateral orifice ; nor out by the orifice, it was flowing in by the trachea. 24 MOTIONS OP Though openings be made into both sides of a iiv3 animal, and the air be admitted till the lungs collapse, and even till the circulation has ceased ; yet, if much vital energy remain, and the two o- penings be properly closed, all the air in the late- ral cavities will soon disappear, respiration com- mence, and the circulation return as before, in a portion of time that seldom will exceed two or three minutes. This singular and sudden absorp- tion of air from the lateral cavities, was observed by Hales and by Van Swieten ; and I have again and again observed it in the numerous experi- ments of my Jate ingenious pupil Dr Sanders, In whatever state or form it is absorbed, we mu >t suppose that it enters the absorbents opening up-* on the surface of the lungs ; and if it there enter the absorbents, why may it not, in a similar stale, after passing along the course of the trachea, en- ter the absorbents opening from the bronchi and pulmonary vesicles a more natural passage, cer- tainly, than that which has been contrived by some physiologists, who have somehow imagined that it maintains its intercourse with the fylood by passing out and in, through pores in the sides of the veins and arteries*. * But the change induced on the blood by respiration is probably owing more to exhalation than to absorption ; for no artery exhales so freely as the pulmonic. A watery injectioa into this artery with a small force, will flow copiously RESPIKATIONV Although an animal may continue to breathe for a short time with a small opening in each of its aides, yet as more air will generally enter by t-hese orifices, during inspiration, than can b'e absorbed, or returned by exp- ration in the same time, the air that enters by the sides will accumulate, and sooi> stop respiration entirely. From considering the difFerent'lengths of the ribs, their different curvatures, inclinations, and attach- ments, we might almost be led, a priori, to suppose that they would not be moved through, equal spa- ces in the same time, either in dilating or contract- ing the thorax. In dilating that cavity, the inter- costales and their auxiliaries are moderated diffe- rently in the different ribs, as may be seen from the different attachments of the muscles that op- pose them. To give a few instances : In the fifth, the sixth, and sfeventh pair of ribs, they are modera- ted by the two recti abdominis ; in the fifth pair to the twelfth inclusive, by the bbliqui extcrni abdomi- nis; in the seventh to the twelfth inclusive, by the diaphragm ; and in the tenth to the twelfth inciu- into the bronchi, and without occasioning any thing like nip. ture in its smaller vessels ; but whether the exhalation-, or not, be the principal cause of change in the blood, pulmonic blood, when exposed to the air through the medium of its vessels, is always observed to change its colour a great deal faster while the exhalants continue to act with a vital energy } than whe* they act slowly and feebly as inanimate MOTIONS OF sive, by the obliqui Interni abdominis. Much variety in the motions of the ribs must at times arise from this difference of muscular attachments ; much va- riety, from irregular proportions of force, velocity, and extent of action ; and much variety, from the numbers, combinations, and the forces of auxili- aries that are occasonally made to co-operate. If some ribs be more moveable or fixed than the rest, and happen to be moved through diffe- rent spaces in the same time, the same distances between them and the rest- cannot be preserved. If a rib, for instance, move faster atlantad than the one immediately succeeding can follow, the dis- tance between them will be increased ; or, in moving sacrad, if it approach the rib that is sacracl faster than the rib that is sacrad retires, the dis- tance between them will be diminished. The numerous and accurate experiments of Haller have clearly shown, that in moving both atlantad and sacrad, different ribs move through different spaces in the same time ; and conse- quently it follows, that in these motions some of the costal interstices were widened, some of them narrowed, and that some, where, contiguous ribs moved together, preserved the same relative breadth. On the general principle, that the intercostales attached to two contiguous" ribs will, upon their contraction, whether the ribs be ascending or de- scending, draw the one that is most moveable to 5 that which is fixed ; it will follow, that when ribs towards the sacral extremity of the thorax are fix- ed by the diaphragm, by the recti, and other ab- dominal muscles, the intercQstaks will, upon their contraction, draw the moveable ribs to those which are fixed, and will make them descend. In the usual dilatations, the costal interstices, to- wards the atlantal extremity of the thorax, are ge- nerally diminished ; a few towayds the sacral ex- tremity* enlarged ; while some towards the mid- dle are very little changed. But though some interstices towards the sacral extremity be enlarged, all the ribs, notwithstand- ing, may ascend ; and all accordingly often do ascend during the dilatation of' the thorax : for r while the muscles whose interstices are enlarged, gradually lengthen, and act only with a modera- ting force against those which are atlantad, they may, and they often, continue to act with a great- er force than those w r hich are sacrad. In the dead body, where the ribs often return to their planes of greatest inclination, the ribs at- lantad being leasi moveable, the costal interstices between them are widened, while the costal in- terstices of the other ribs in the lateral aspects are considerably diminished, and the muscles that oc- cupy them very much relaxed. Hence, in per- forming the operation of paracentesis on the dead body, as far down as the sixth or seventh rib., we are often obliged to elevate the ribs ? as in inspira- 528 MOTIONS op- tion, to enlarge the interstice where the operation is to be performed. In many cases, respiration is performed without any motion whatever of the ribs ; the muscles that alternately contract and relax, being the ab- dominal muscles and diaphragm ; the intercostaks in these cases doing nothing more than preserving the ribs perfectly steady, and furnishing fixed points to the diaphragm, by which it may act on its cordiform tendon. In respiration, the motions of the ribs may therefore be either greater or less, or suspended entirely, according to circumstances. Iri inaking experiments on live animals, even where the species of respiration is the same as our own, anatomists must often witness phenomena that can only be phenomena of rare occurrence. After considering that the actions of the dia- phragm in ordinary cases, are different from its ac- tions in sneezing and coughing, and these again different from its actions in laughing and hiccup ; after considering that our breathing is varied by heat and cold, by pleasure and pain, by every Strong mental emotion, by the different states of health and disease, by different attitudes and dif- ferent exertions, -we can hardly suppose, that an animal under the influence of horror, placed in a forced and unnatural attitude, its viscera exposed to the stimulus of air, its blood flowing out, man/ of its muscles divided by the knife, and its ner- vous system driven to violent desultory action RESPIRATION. from excruciating pain, would exhibit the pheno- mena of ordinary respiration. In that situation, its muscles must produce many effects, not only of vio- lent but irregular action \ and not only the muscles usually employed in performing the function, but also the muscles that occasionally are required to act as auxiliaries. If different anatomists, after see- ing different species of animals, or different indi- viduals of the same species, respiring under diffe- rent experiments of torture, were each to conclude, that the phenomena produced in these cases were analogous to those of ordinary respiration, their difference of opinion, as to motions of ordinary respiration, would be immense; and some, from seeing the ribs that are sacral not ascending so fast as those which are atlantal, and consequently some of the interstices enlarged during inspiration; might hastily conclude, as Sabatier has done, though not with his usual degree of reflection, that the intercostal* are muscles of expiration*. THE INTERCOSTAL MUSCLES. , IN the interstices which they occupy, these mus- cles at certain places form two strata or layers, an * Huitieme Memoire sur les Mouvemens des Cotes, et sv.v '!' Action des Muscles Intercostaux. LI 030 MOTIONS Otf' external and internal, or peripheral and cfentr&f; and in each row, from the rib which is atlantad being, more fixed than that which is sacrad, their attachment to the former is considered as their origin ; their attachment to the latter, as their in- sertion. The fibres of the peripheral layer beginning at' the vertebras run sacrad and sternad ; whence, measuring from the vertebrae, they necessarily act by a longer lever on the rib that is sacrad than on that which is atlantad*. This layer, in general, is observed to terminate not far from the junction of the ribs with their cartilages ; for, had it been continued as far as the sternum, its fibres there would, measuring from the sternum, have neces- sarily acted, through the medium of the carti- lages, by a longer lever on the rib which is atlan- tad than on that which is sacrad. The fibres of the central layer, beginning at the sternum, run sacrad and dorsad ; and thus,- mea- suring from the sternum, necessarily act, through the medium of the cartilages, by a longer lever OB the rib that is sacrad than on that which is atlan- tad*. This layer, in general, is observed to ter- minate near the angles of the ribs ; for, had it been continued as far as the vertebra, its fibres there would, measuring from the vertebne, have * See p. 281, 282. RESPIRATION. 531 begun to act by a longer lever on the rib which is atlantad than on that which is sacrad. Where the two layers are found together be- tween the cartilages and angles of the ribs, they necessarily decussate ; but in that situation, not acting particularly on either of the two extremi- ties of the ribs, they both act by a common lever in drawing the moveable rib to the fixed, and, in drawing it atlantad, produce a kind of rotatory motion, by which the atlantal margin of the rib is turned centrad, and the sacral peripherad. In this motion the rib moves, as it were, on an axis extending from its sternal to its dorsal extremity ; and the levers of the fibres of both strata are here fcqual to straight lines drawn from the axis perpen- dicularly to the planes in which the fibres are situ- ated respectively. From the conical shape, how- ever, of the thorax, these lines, especially In the ribs connected with the sternum, will, at any given place between their sternal and dorsal extremity, be longer in the rib that is situated sacrad than in that which is atlantad : and hence it will follow, in this motion also, that the fibres composing the two strata will each act by a longer lever on the rib which is sacrad than on that which is atlantad ; a lever which, during inspiration, will be lengthen- ed, where the cartilages force their ribs dorsad and laterad, and increase their distance from the axis of motion, without being affected in its length by a change of obliquity in any of the fibres, 532 MOTIONS OF' But notwithstanding that all these levers are* strongly in favour of the motion atlantad, it must be recollected that the intercostals cannot elevate the ribs without the gradual expansion of the lungs ; a gradual expansion that is not to be view- ed as merely an effect, but rather as a cause of this elevation. From the intercostals acting with a force not able at once to resist their moderators, and to support a great deal more than a fourteenth part of the pressure of the atmosphere *, the addi- * " For though a man, by a peculiar action of his mouth find tongue, may suck mercury twenty-two inches, and some men twenty-seven or twenty-eight high, yet I have found by experience, that by the bare inspiring action of the Diaphragm and dilating thorax, I could scarcely raise the mercury two inches ; at which time the Diaphragm must act with a force equal to the weight of a cylinder of mercury, whose base is commensurate- to the area of the Diaphragm, and its height two inches ; whereby the Diaphragm must at that time sustain a weight equal to many pounds. Neither are its counteract- ing muscles, those of the Abdomen, able to exert a greater force. " For, notwithstanding a man, by strongly compressing a quantity of air included in his mouth, may raise a column of mercury in an inverted syphon to five or seven inches height, yet he cannot, with his utmost strainings, raise it above two inches by the contracting force of the muscles of the Abdomen. Whence we see that our loudest vociferations are made with a force of air no greater than this." HALRS, Statks, vol. z\ iExp. cxvi. RESPIRATION. , 533 fional force to support that pressure must, during their contraction, be principally supplied by the air within the lungs. In proportion, therefore, as the thorax expands, the external air rushes into the lungs ; and expanding the lungs in the form of a cone, the lungs are made to act like a wedge or inclined plane, and by their expansion to cause the ribs slide from their base towards their apex ; or, in other words, to move them at the same time peripherad and atlantacL And hence it is, that merely by inflating the lungs with air in the dead body, we can elevate the ribs, as in inspiration, without the assistance of the intercostals. Should any, however, accustomed to view ihe expansion of the lungs as rather the effect than the cause of the ribs moving atlantad, and so not be inclined to admit a fact that is contrary to their previous habits of thinking; to conciliate those habits, the fact may be expressed in a diffe- rent manner, by saying, that the muscles, in di~ lating the thorax, induce the air to rush into the lungs, and derive much assistance from its pres-r sure and expansion. THE INTERCOSTALS IN TWO LAYERS. THE supposition that these muscles are in two layers, that the one might depress, and the other elevate the ribs in respiration, is a supposition that is now obsolete, and a supposition that appears to MOTIONS OF have been formed by the very witchcraft of irna gination, in defiance of all observation and experi- ment., A single layer, unless the course of its fi- bres had been changed at the sternal and dorsal parts of the interstices, must have produced oppo- site effects on the sternal and dorsal extremities of the ribs. A single layer could not so effectually have resisted hernias as two layers, whose fibres de- cussate ; and with a single layer, the motions of the ribs sternad and dorsad could not have been performed with the same steadiness that they are by two; the central layer moderating the periphe- ral in the motion dorsad, and the peripheral mo- derating the central in the motion sternad. THE FIBRES OF THE INTERCOSTALS RUN OBLIQUELY ACROSS THEIR INTERSTICES, THE peculiar actions assigned to these muscles are principally owing to their obliquity. By their obliquity, their length and their quantity of con- tractility are augmented ; by their obliquity, they are able to perform more extensive motions with proportionally fewer degrees of contraction, find, consequently, with less disturbance to their nerves, their veins, their arteries, and their absorb- ents* ; by their different obliquities, the fibres of RESPIRATION. 533 the two layers decussate, and more powerfully re- sist the protrusion of the viscera ; by their different obliquities, they elevate the ribs at both their ster- nal and dorsal extremities ; and by different obli- quities, the two layers moderate one another in the ^notions of the ribs sternad and dorsad. _ ABDOMINAL MUSCLES. THERE being few motions or attitudes of the trunk, or compressions of the abdominal viscera, in which these muscles are not concerned as mode- rators, motors, or directors, the state of respiration is not only varied with their different functions* but made to contribute to the steadiness and ener- gy of their exertions : thus, in their strong and vi- gorous exertions to change or preserve the atti- tudes of the trunk, or compress the viscera, the ribs are previously somewhat raised, or drawn atlantad, and, as fixed points, made lo resist the motion sa- crad with more than usual degrees of steadiness this steadiness, however, docs not proceed, or pro- ceeds, but little, from the intcrcostals. These muscles, opposed in their functions by the great pressure of the atmosphere from without, and not having strength to elevate the ribs unless assisted by a like pressure of the atmosphere from within, the abdominal muscles, which are always favour- ed by the pressure from without, would, with no great exertion, depress the ribs, and expel the air. 536, MOTIONS OF while the intercostals could have no means an4 no power to prevent its egress. To account, therefore, for the more than usual stability of the ribs in cases of extraordinary exertion, we must have recourse to those muscles by which the e- gress of the air is prevented, or by which the quan- tity issuing from the lungs in a given time is ac- curately regulated. Now, these are the muscles of the os hyoides, of the cartilages of the larynx, of the velum pendulum, of the tongue, and of the lips. By these muscles the passages through the larynx, the isthmus faucium, the mouth, and the nostrils, may be widened, narrowed, or entirely shut ; one passage shut, and another opened ; or the whole of them shut, and the whole of them opened, as the will directs, and as circumstances require. It is hence that these muscles, by re- taining the breath after full inspirations, or by re- gulating the quantity that issues frpm the lungs in a given time, cause the air in the lungs to afford that support or stability to the ribs, which enables the diaphragm and abdominal muscles to act with so much steadiness and energy in giving attitude and motion to the trunk, in compressing the vis- cera, in emptying the stomach, in* expelling the foetus, feces, and urine. Nor are these the only general effects arising from the muscles that com- mand the passages to and from the lungs: as men- tal emotions do not unfrequently extend their in- fluence to respiration, the same muscles make res~> RESPIRATION, $37 piration also, in its turn, to extend its influence to the mental emotions ; and hence it is that we see persons under surgical operations, or in violent pain, holding hard their breath, and trying, as it were, to lessen their sufferings, or to confirm their resolution in supporting them : A fact too obvious to have escaped the admirable Shakespeare, who makes Henry 'say, in addressing his soldiers at the siege of Harfleur, Now set the teeth, and stretch the nostril wide, Hold hard the breath, and bend up every spirit To its full height. As respiration is thus made to favour the mo- tions and attitudes of the trunk, so these motions and attitudes are made in their turn to favour res- piration. There are scarcely any who require to be informed of the happy effects of moderate ex- ercise upon this function. And as for the attitudes; in phthisis often, and generally in asthma, and in hydro-thorax, where the diaphragm is forced to make great exertions, in dilating the chest, the e- rect posture is adopted instinctively, and is some- times indispensible, as in that posture only, the ab- dominal viscera, without any kind of muscular exertion, are disposed to movesacrad by their own weight. To explain the phenomena observed by Haks* * See note p. 532, 538 MOTIONS OF jn trying to raise a column of mercury by tnc force of the air when inspired and expired, it is obvious, that air contained in the mouth, when it is inhaled, may be driven to the lungs with a greater force than by the mere pressure of the at- mosphere ; as the pressure of the atmpsphere, in this case, continues to operate on the muscles from with- ; ut, and besides is assisted by whatever force the muscles exert in their contraction. In the same way, these muscles of the mouth may give an ad- ditional impulse to the air as it passes along in the time of expiration, or, by shutting the valvular a- pertures behind, may give a distinct impulse of f heir own. AUXILIARY MUSCLES OF RESPIRATION, FROM repeated .observations on the dead and li* Ting body, I enumerated these muscles, without any remembrance at the time of those that had been reckoned auxiliary by Haller. Our two enu- merations, however, coincide, except in one in- stance, in which I have viewed the serrati magni as muscles occasionally employed in expiration*. The truth is, that the scapulae being in their usua.1 situation, some of the fasciculi of these muscles proceed atlantad, and ^some of them sacrad, to thq 381, RESPIRATION, bases of the scapulse ; and that not a few of them, when the scapulae are depressed, and the ribs in their planes of greatest inclination, seem obviously calculated to move their ribs sacrad: for although they appear to ascend from the sides, they ascend not so high as the dorsal articulations of their ribs, nor, consequently, so high as their axis of motion; arid hence the scapula? are always depressed in vi- gorous expirations, and these fasciculi made to as- sist the abdominal muscles. On the other hand, it must be acknowledged that the same fasciculi al- ways oppose the abdominal muscles, by drawing their ribs dorsad and laterad*, and in drawing them sacrad, always act with a less and less force as the scapulas are elevated, or as the inclinations of the ribs are changed, till at last, by the change, they come to draw them a little atlantad ; and hence, partly, the cause why the two scapulae are likewise elevated in very full and vigorous inspi- rations. The effects of the two. serrati postici super iores, as motors of the ribs, are increased by inflections of the neck sternadj the same inflections, with si- * The cartilages of the ribs connected with the sternum, by forcing their ribs dorsad and laterad, promote the dilatation ; and by forcing them sacrad Curing expiration, promote the contrac- tion. The diaphragm also is made to co-operate with both the intercostal and abdominal muscles in enlarging and diminishing the capacity of the thorax. 540 MOTIONS OF RESPIRATION. rnilar inflections of some of the highest of the dor-* sal vertebrae, enable the trapezii, the rhomboidei, and the levatores, to increase their extent of action on the scapulae, while the elevations of the two scapulse assist not only the serrati magni, but the Jitbcl&uii, the serrati antici, the perforates, and latis- simi dorsi, to elevate the ribs and support the inter- costals ; and hence we observe, that in phthisis pul- monalis, in dyspnsea and sneezing, the scapulae are .drawn atlantad and sternad, the shoulders round- ed, and the head and neck placed in the positions that are most favourable to these muscles, so far as they contribute to enlarge the thorax. The simple knowledge of the origin and insertion of the other auxiliaries supersedes the necessity of any explanation of their mode of operating ; al- though I may add, that the sternomastoidei, when the body has been lying horizontal and supine, have sometimes been unable to raise the head from the pillow underneath, from the want of a fixed point in the sternum, when the recti abdortiinis were incapable of resisting its motion atlantad*. * " Graviori morbo decumbentem duo simul invisunt medicu Vultum, linguam, aliaque exploranda simul examinant. Inter- base inopina quadam tensione musculorum abdominis aliquid hinc monstri ali indicat medicorum alter ; alter nil quod timen- dum foret, expertus, timenti socio : Manum, inquit, admovea- jnus ambo simul, non quidem festinam, sed attentam. Dic- tum, factum. Ilk musculorum tensiones non continua^as, se4 ( 341 ) CHAP. XVII. MOTIONS OF THE ALIMENTARY CANAL, W HERE the food is not regularly in contact with the body, nor a sufficient quantity of nourishment conveyed into the system by the absorbents open- ing from without ; or where the food necessary for the system is not fitted to enter the absorbents till it undergo some preparation, the animal is always provided with a stomach, if not with an alimenta- ry canal; with organs of deglutition and digestion; with organs also of mastication, if the aliment be fexitate identidem interpolatas mlratur ; magis autem miratur placid um at que imperterritumsocii vultum,nullo hinctimore, nul- la cura percitum. Scilicet hinc decumbent! occasionem subinde pepererat ea quae circa pedes gerebantur, animadvertendi, utquc eadem facilws animadverteret, caput eodem momento aliquan- tisper levandi. Novit anatomes gnarus, supino corpore jacen- tem caput attollere non posse, nisi trahentibus musculis mas- toideis sterno mobili affixis, hos autem conari frustra, ni muscii* lorum abdominis ope sternum simul reddatur immotum. Sat g&pienti." HALLEB., JDisfutat. Anal. Select, vol. vi. p. 759. 542 MOTIONS OF THE such as to require them ; and with absorbents opening from within, to Convey the nutritious part of the food, either directly, or through the me- dium of some other vessels, to tjie different organs, In this canal the food is brought to the same temperature with that of the . system ; is always mixed with a variety of animal fluids from glan- dular ducts, or exhalant arteries ; the nutritious part separated from the fsecal ; and the faecal after- wards discharged through the sphincter termina- ting the canal. From the fluids exhaled into the canal being, excrementitious, and from the exhalations being often more copious during the periods of sickness than of health, we are able to explain how the quantity of fasces may often be greater than the quantity of ingesta. From knowing likewise that disease may originate, or be greatly aggravated, by allowing the breath and perspirable matter of the sick to accumulate in the chamber around them, we are led to suspect that accumulations or ab- sorptions of the fluids exhaled into the alimentary canal, must be fully as injurious as the inspiration of air that is tainted; and may thus explain the extensive utility and success of that practice which has been lately reduced to a system, and by which both the accumulation and absorption of these' noxious exhalations are prevented * * See page 246; ALIMENTARY CANAL. In the human species, the alimentary canal com- Snences at the lips, and terminates at the orifice, which is called anus ; from the lips to the isthmus faucium it is named the ihouth ; from the isthmus to the cncoid cartilage, the pharynx ; and from the cricoid cartilage to the diaphragm, the oesophagus* The oesophagus, as soon as it passes the dia- phragm, dilates into a sac, which is called stomachy the entrance to the stomach is tile cardia, the pas- sage out of it the pylorus. The pylorus opens inte the intestine. Under this name the canal under- goes numerous convolutions; these convolutions are all, more or less, contained in the folds of peritoneum. The peritoneum is that membrane which lines the whole abdominal parietes on ti eir central aspect. Between these parietes and the pe- ritoneum, are situated all the abdominal viscera . and where these viscera are seen to project beyond the parietes, they have forced the peritoneum be- fore them, and are lodged in its folds. On open- ing, therefore, the abdominal cavity, the peritone- um is interposed between the eye and every vis- cus that is named abdominal; and wherever it adheres is termed their peritoneal coat. Between tfiis membrane and the dorsal parities , are situated all the various convolutions of the intestine; and where these convolutions project at a distance from the parietes, the peritoneum completely sur- rounds them, the part of its fold between the con- volution and the parietes being termed the mesente- 3 544 MOTIONS' OF THE ry. This part of the fold which is termed mesen- tery, contains the nerves, the arteries, the veins, and the lacteals, more immediately connected with the convolution ; assists them in performing the of- fice of a ligament to the intestine; and performs^ besides, as the peritoneum does every where else, the several functions of a mucous membrane. In all cases where the viscera are in contact- with the parietes, there is no mesentery ; nor at the place of actual contact is there any peritoneal- coat. In a young subject, the peritoneal coat is easily separated from the convolutions of the intestine, To do this, the anatomist has only to divide the intestine with the edge of his knife, to lay hold of one of the ends, and to draw it towards him : the intestine will come out of its peritoneal coat as out of a sheath ; and if the sheath be afterwards inflated, it will exhibit the general appearance and the convolutions of the intestine that was lodged in its folds. The intestine is divided into different portions. From the pylorus to the commencement of the mesentery it is called duodenum ; from the com- mencement of the mesentery, and through all its convoluions, as far as the right iliac region, it is the jejunum and Hewn ; which, if divided into five equal parts, the two first will be the jejunum, and the three last the ileum, although the distinction should not be retained. In the right iliac region ALIMENTARY CANAL. 543 the intestine is suddenly increased in diameter, nnd likewise somewhat changed in its form. On the change of its diameter it is named colon ; to- wards the commencement of the colon, where there is no mesentery, the ileum enters laterally its sinistral aspect, and in such a manner, that what it discharges into the colon cannot return ; the part of the colon that is sacrad of the place where the ileum enters, is the caput ccscum coli, front which proceeds a small intestinal process, named the appendicula vermiformis. From the right iliac region^the colon proceeds through the right lumbar to the right hypochondriac region ; from the right hypochondriac, runs transversely to the left hypo- chondriac ; and from the left hypochondriac, ad- vances through the left lumbar to the left iliac re- gion, where, turning a little towards the right, and running along the sternal aspect of the os sacrum, it terminates the alimentary canal. Where it oc- cupies the regions on the right, it is the right co- lon ; where the regions on the left, the left colon ; where it runs transversely, the transverse colon; and where it runs straight along the os sacrum, it is named the rectum. At the liver it exhibits the hepatic flexure ; at the spleen, the splenic flexure ; and in the left lumbar and iliac regions, the sig- moid flexure. The portion of the peritoneum Which fixes it in the right lumbar region, is the , ligamentum dextrum ; and that which fixes it in the left rumbar' region, the ligamentum sinistmm* M m 540 BIOTIONS OF TH2 From its commencement to its termination, the whole alimentary canal is surrounded with mus- cles ; although, from the diaphragm to the nus r no muscular fasciculi are described separately, ex- cepting the. JLevatores ani, Sphincteres an!, Transversi perinaet ; the other corneous fibres being considered as onl>; parts of what is denominated the muscular coat, and of which in the stomach there are evidently two strata. The muscles of mastication are these enumera- ted under the motions of the basilar maxilla ; those of deglutition are the muscles of the lips, of the tongue and os hyoides, the several muscles of the isthmus faucium, of the pharynx and oesophagus. When the mouth is shut, and the tongue has forced the food through the isthmus, the several muscles constricting the pharynx act in succes- sion, yielding before and contracting behind the object to be swallowed, till it reach the stomach, *. In propelling the food through the region of the, pharynx, the muscles are always greatly assisted by the pressure of the atmosphere acting through the nostrils ; and hence it is, that when the mouth . and the nostrils are shut, the deglutition is not only difficult, but sometimes impracticable. They are likewise assisted by the lubricating ALIMEHTARV CANAL. 547 which is mixed with the food ; and hence it is, that the salivary glands, the parotid, the submax- illary, and the sublingual, are always found ia those situations where they are regularly excited into action by the motions of the parts employed iri mastication. In cases where no saliva is secre- ted; or secreted in too sparing a quantity, the so- lids that are dry require to be moistened artifi- cially with water, or some other liquid ; a practice that is never omitted by those who have what is termed a dry mouth, a defect which in some fa- milies is hereditary. In swallowing any thing liquid or solid, the tongue is observed to press against the palate ; the larynx, by means of the thyrohyoidei, to start atlantad ; the thyroid cartilage to press closely a- gainst the epiglottis, the epiglottis to press closely against the cartilage, and the larynx to shut till the food has passed into the oesophagus, If the quantity of food, however, be so small as not to excite the action of the muscles, or to arouse the feelings of instinct, the orifice of the larynx will in- that case be imperfectly closed ; and then often may a portion of the food get into the windpipe. Upon such an accident, it is not the muscles in the immediate vicinity of the injury that are thrown iiito action, but all the muscles, whether near or distant, that are calculated either to re- move the cause or alleviate the effect. Mm 2 -MOTIONS OF THE When the food is in the stomach, its return it prevented partly by the diaphragm, whose fibres decussate, and form, as it were, a species of sphinc- ter around the oesophagus, partly by a slight change of direction in the oesophagus, that advances ster- nad to pa^s through the diaphragm, and partly by a change of position in the stomach ; a change of position that is always observed to arise from dis- tension : For, in proportion as the stomach is dis- tended, its atlantal aspect is inclined dorsad, its dorsal sacrad, its sacral sternad, its sternal atlan- tad ; and in this way an angle being formed upon the oesophagus, an effect is produced, that com- pletely answers the purposes of a valve. In cases of vomiting, the angle is removed by the abdomi- nal muscles and diaphragm compelling the sto- mach to assume the position that it has when mpty, or when nearly empty. As this pressure, however, of the diaphragm and abdominal mus- cles, must, cKteris*. paribus, always be less, as the distension of the stomach" is diminished ; although, the position be more and more favourable, the ex- tent of inspiration and of muscular contraction, in the efforts of vomiting, must a!v>ays be greater in proportion as the stomach is emptied of its con- tents : And hence the practice of drinking w^ater, and distending the stomach, in order to lessen the. cftbris of the muscles employed in vomiting. As a sense of compressson is usually accomna*- ALIMENTARY CAN At, frier! with a sense of fulness ; and as, from the want of ordinary compression, when the storr.ach is empty, we ate naturally subjected to a sense of hunger, many, to prevent this uneasy feeKng, when they are necessarily exposed to fasting, Lave recourse to the u.se of a compress and bandage; and not only individuals^ n\.m ca-ual suggestion, but whole tribes, from .established custom, if we may credit the relations of UavcUers with respect to some of the Tartar hordes, -.y the action of the diaphragm and abdominal muscles, and suc- cessive contractions of the circular fibres belong- ing to the .--tomach, the food is propelled through the pylorus into the intestine ; by successive edi- tions of the circular fibres of the intestine, it is then propelled towards the rectum, while the fas-, cal part, accumulated in the rectum, and in the neighbouring portion of the colon, is afierwaids forced through the sphincter am by the abdomi- nal muscles and diaphragm, assisted, if necessary, by full inspirations, and by the muscles that shut the mouth, the isthmus faucium, the nostiils, and the glottis. The longitudinal muscular fbres of the intestine are not very obvious in the human -.pecies, roi in- deed in many of the lowef^animaL ; and hence, in transverse incisions of the iu, the edges ( f .Y;e m-.ii]d are but little letiacteJ. The icngUbdj al bands of the colon evidently peiioim the qiLce of 4 MOTIONS OF THJE ligaments ; and continuing to act in that capacity even after deulh, may easily be demonstrated tq be the cause of the cells of the colon. At the same time, considering the great variety of forms, functions, colours, and irritabilities of different muscles, I can hardly presume to assert, that the fibres of these bands are not also muscular. The motions produced by the circular fibres of the intestine have been mmedpftdrtateG, and have been compared to the motions of a worm ; yet the motions of the worm and of the intestine are widely different : The worm is seen to inflect its body sternad, dorsad, dextrad, and sinistrad ; to shorten jt, lengthen it ; to increase or diminish its general diameter ; and to cause the motions of a number of parts to combine at a time in effecting these changes. But as for the intestine, it cannot |)e inflected s,ternad, dorsad, dextrad, sinistrad ^ and cannot be either lengthened or shortened by the contractions of its transverse fibres. Be- sides, the contractions of these fibres, proceeding from the stimulants within the intestine, and not being regulated by the general influence of the sensorium, are quite unconnected. On a curso- ry view, they indeed may appear to follow one another in a kind of succession, like wave upon wave ; but they follow at no determinate distanc^ in time or in space ; and a portion of intestine in- tercepted between ligatures, exhibits its motioi& ALIMENTARY C ANA L . 551 independent of those which precede or which fol- low. In morbid cases, where the order of nervous ex- citement is inverted, the contents of the intestine are sometimes thrown back upon the stomach, and discharged by the mouth. The rate at which the contents are moved by the muscular contractions of the intestine, will ne- cessarily be different in different individuals ; and even in the same, at different times, much will de- pend on the force and velocity of the motor fibres acting behind, and on the resistance of the mode- rating fibres opposing them before. The action of the fibres, again, will depend on the state of their nerves ; and the state of the nerves, upon the excitement induced by the contents. In all cases, a resistance will be made by the valvulae conniventes ; and this resistance will be greater or less in proportion to the fluidity of the contents, the fluidity being regulated by various circum- stances, but principally by the state of exhalation and absorption that takes place in the canal. If natural Evacuations were regularly to occur in twenty-four hours, the average rate of motion in the contents, through an intestine of twenty-four feet, would be a foot in the space of an hour, or an inch in five minutes ; or if through an intes- tine of thirty-six feet, a foot and a half in the space of an hour, or nearly an inch every three 552 MOTIONS OF THE minutes. But as every portion of the intestine enjoys a separate independent power, and may act with a different force and velocity according to circumstances, these calculations, founded on hy~ pothesis, are of little use in illustrating its func- tions. As a constant discharge of the flecal matter would necessarily be attended with much incon- venience, in all animals the intestine, towards its sacral extremity, is less irritable, and slower 'in its motions, than towards the atlantal ; is in some ani- mals considerably enlarged in its diameter; and in others is connected with reservoirs, under the name of capita caeca. By these contrivances, the matter being generally found to accumulate, , or to continue stationary for a while, towards the sphincter, the animal enjoys a certain degree of discretionary power in choosing the time and place to discharge it ; though, if the accumula- tions have been large, the evacuation is seldom complete ; the animal system not being fitted to bear sudden and extensive changes without a pro- portional degree of injury. And hence we see persons often convulsed in emptying the bladder, and others faint, not merely from haemorrhages, but from a sudden and copious discharge of drop- sical water, to the pressure of which the system had for some time previously been accustomed. From the discharge of the faecal matter not be- ing -constant, the evacuation is not entrusted to the ALIMENTARY CANAL. 55$ jnere peristaltic motions of the viscera. An in- stinctive warning is usually given by a particular uneasiness at the sphincter ; and after the warn- ing, a certain time is, generally allowed for the necessary preparation. If in this time the will refuse to comply with the suggestion, the warning is repeated with more urgency; and should no warning have the effect, the instinct, as in cases where no law of morality opposes, imperiously takes the command of the muscles, and expels the fasces in defiance of volition. The muscles employed, or that may be employed, in the ex- pulsion, are the circular fibres of the intestine, where the faeces are accumulated ; and all the muscles that directly or indirectly, contribute to compress the abdominal viscera. Their modera- tors are the Levatores am", Transvcrsi perinasi, Sphincteres ani, Coccygei, Curvatures coccygis ; which, after moderating the motor muscles, be- come motor muscles themselves ; and acting suc- cessively in compressing the rectum, expel any remains of the faeces that may be lodged towards the extremity of the canal. While the transversi permed and sphincteres ani are gradually contracting, they are drawn a little atlantad and sternad by the levatores, which are at 554 MOTIONS OF THE the time compressing the rectum ; the integuments on each side of the anus, attached to the sphincte- res ani through these muscles, moving a little me- siad and atlantad, the os coccyx advancing ster- nad by its own elasticity and the action of its mus- eles, and the bulb of the urethra dorsad and atlan- tad, from its connection not only with the sphinx feres, but transversi perin&i. The effects of respiration in assisting the muscles that are employed in the process of digestion, have not yet been mentioned, though certainly the pres- sure, and alternate motion occasioned by the dia- phragm and abdominal muscles, cannot be with- out a considerable influence on the stomach, the Jiver, the spleen, the pancreas, and the intestine. They not only are varied, but regularly accom- modated to every attitude which we assume, and to every exercise in which we are engaged ; and in proportion as they are defective, it is gene- rally observed that the processes of digestion are more or less accurately performed. Nay, if we may judge from the consequences of frictions, and from the effects of motion and pressure upon the parotid and subm axillary glands during mas- tication, we may fairly presume that respiration contributes not only to promote the circulation, but also the secretions, exhalations, and absorp- tions, that take place in all the abdominal viscera. Nor will it be an argument against the conclusion, that these functions are also continued when .tha ALIMENTARY CANAL. viscera are lodged in a hernial sac ; for there is not a sac, and there cannot be a sac, communicating with the abdominal cavity, in which the viscera can be totally exempted from the effects produced by respiration ; although in such cases they may acquire additional strength, and additional connec- tions, by which they may always be somewhat ac- commodated to the change of circumstances. Yet with all these accommodating changes, and with every possible assistance from art, they never can perform their natural functions with the same ex- pedition, safety, and force, and under as many va- rieties of circumstance, as they did when in their original situation, and when they were more com pletely subjected to the regular agitation and pres- sure arising from the diaphragm and abdominal muscles. CHAP. XVHL MOTIONS IN THE EXPULSION RETENTION OF URINE. 1 HE muscles employed in performing these me- $ions, are the MOTIONS IN THE Abdominal muscles, * Diaphragm, Constrictores vesicae, seu detrusores urinx, Sphincter vesicae. In the male, Cumpressores 'prostatar, L^ vatores ani, Sphincter ani, 'Sphincter ani alter, Transve.si peritiaei, Accelerators unuae. After the urine is secreted in the kidneys, it is propelled by the successive muscuiar acu-.n ot die ureters into the bladder; and the two ureteis en- tering the bladder with an obliqu ty thai is n.ade to answer the purposes, of valves, the urine accu- mulates as long as the sphincter vesica is shut. This accumulation, sooner or later, creates an un- easy sensation at the sphincter, and disposes that muscle to relax. To remove the sensation, as soon as an opportunity occurs, and the will coiiLer.ts, the constnctores are thrown into action, assisted by the pressure oi the intestines, and occasional iy by the diaphragm and abdominal muscles, till ibe \\ hole of the unne is forced through the sphincter into the urethra. As }he urethra Las no sphincter to resLt the current, the urine f^s through its distal extremity with a force proportioned to the vis a tergo ; and if, after the evacuation of the "bladder, a few drops should remain in the urethia, the' contractions of the sphincter and compressores pro*tai( propel them onward towards the bulb ; A.ND RETENTION OF UHINE. 567 from whence, by the successive contractions of the different fibres composing the two acceleratores, they are forced distad through the outward orifice, In this function, the acceleratores, connected with the two transfer si perincei, and, through the sphincter or sphinctores ani, with the levatores, re- ceive occasionally considerable assistance from these muscles ; the two transversi compressing the urethra, by opposing one another in the directions dextrad and srnisliad, and by drawing it a little towards the rectum or sphinctsres ani* ; while the levatores, by drawing the sphincter or sphincter es ani atlantad and sternad, must indirectly lengthen the bulb, press it against the arch -of -the pubes, and stretch the fibres composing the two accelera- tores. And hence, in evacuating the canal of the urethra, we are often conscious of the effects re~ suiting from the two levatores- ani. REMARK. IF the sphincter vesictz refuse to yield to the con- strictores and abdominal muscles, the bladder is soon prceternaturaHy distended'; though during the distension the urine does not accumulate so fast as 1 iri ordinary cases : And hence it is, that after the * From acting on the same point, they cannot possibly d? late the urethra dextrad and smistrad, as is sometimes supposed*. 58 MOTIONS OF THE accumulated urine is discharged by the catheter or trocar, the secretion in the kidneys becomes more copious, and a much greater quantity of u- rine flows into the bladder, and within a few hours from the operation, than had been collected du- ring the whole time of the obstruction ; a proof that the fluid from which the urine is formed in the kidneys, had during the obstruction been re- tained in the blood, and accumulated in the san- guiferous vessels, where it must have had a ten- dency to injure the other functions of the system. CHAP. XIX. MOTIONS OF THE MALE ORGANS OF GENERATION. 1 HESE organs are the scrotum, the testes, the itas& ^eferentia^ the vesicula seminales, the prostate gland? and the two corpora, cavernosa penis. Their mus- cles which are n^med #nd described by anatc^ mists, are the MALE ORGANS OF GENERATION. Darti scroti, Cremasttres testiuro, Compreasores prostatx,. Ercctores penis. As the cavities of the scrotum, in which the tes ?es are contained respectively, are, like the inte- guments, frequently observed to contract in con- sequence of mental emotions, though not in con- sequence of any volition, and, like the integu- ments, observed to contract in consequence o cold, and, like the integuments, to be more lax during the later than during the earlier periods of life ; many anatomists, from viewing these phe* nomena as analogous to those of the cellular mem- brane, and from finding nothing in the substance of the scrotum that does not resemble either inte- gument or cellular membrane, have, not without some appearance of reason, denied the existence of such muscles as those which have been denomi- nated darti. The cremasteres assist not only in supporting the testes and spermatic cords, but, by their contrac- tions, seem also to compress them ; and, though not in consequence of any volition, are occasion- ally observed to retract the testes (if these retrac- tions be not more owing to the vessels of the cords) as far as the rings of the obliqui externi ab- dominis. The functions of the two compressors prostates are implied in their names. They sometimes ap- pear as. if they were portions or continuations of 550 MOTIONS OF THE the levatores ani, and sometimes have their appro- priate origins in the bones of the pubes*. The erectores penis are improperly named : They compress the crura, draw them dorsad and sacrad, and opposing one another in the lateral di- rections, prevent them from moving dextrad or sinistrad. They have very little influence in cau- sing erection, excepting so far as they act upon the vessels. The erection is owing to the force of the fluids distending the cells of the corpora cavernosa, and may be produced by distending them with air, or any other fluid, in the dead body. In the living body, it generally proceeds from that inequality of the circulation, by which the blood is more accelerated in the arteries' than the veins ; an inequality that is often oc- casioned by mental emotions, though not by volition ; by mental emotions affecting different- ly the arteries and the veins; which here, as in the eye, the brain, and some other parts, have a different course, are supplied by different branches of nerves, and exposed to considerable differences' of action, from the organs which surround them. In the evening of life, when the sensibility is less acute, the mental emotions less energetic, the fluids scanty, and the circulating system comparatively feeble, there are few erections that do not proceed from either a disease of body or of mind, or from * See Albini Historia Musculorum, lib. iii. cap. 98, MALE ORGANS OF GENERATION, 361 ii distension of the urinary bladder, retarding the motion of the blood in the veins. When tile two corpora cavernosa are distended, the effects of the muscles named erectores become more conspicuous, partly in proportion as their action is extended, and partly in proportion as the two corpora cavernosa are elongated, and their 1 distal extremity removed further from the centre of motion. In propelling the fluids forward to the cells, and also in drawing the corpora caver- nosa dorsad and sacrad, the erectores either are, or may be assisted by the levatores ani, acting through the medium of the sphincter ani and bulb of the urethra, and partly also by the transversi perinai. When drawn sacrad in a state of erection, they re- turn to their place by their own elasticity, and by that of the ligament which connects them with the pubis. When the seminal fluid enters the urethra, it is propelled by the same muscles that propelled the urine. As for its motion through the vasa defe- rentia, and the numerous ducts of which they are formed, supposing it propelled through their dif- ferent convolutions by circular fibres acting in succession ; yet if these fibres, as proportioned to the diameter of the tubes, be not more distinct and less pale than those of the intestines, the urinary bladder, and many of the arteries, it is hardly pos- sible that they ever can be objects of ocular de- monstration. Nrv ( 562 > CHAP. XX. MOTIONS OF THE FEMALE ORGANS O? GENERATION. I H-CSE organs are the ovaria, the Fallopian the uterus, the clitoris, and the vagina. The Fallopian tubes are observed, in consequence of the sexual intercourse, to change their position to grasp the ovaria, and after the ova have burst thro' their covering to convey them to the uterus.. But whether or not these functions be performed by muscular fibres, may with some remain a sub- ject of doubt y. for, supposing that muscular fibres \vei-e present, we could hardly expect them to be- more obvious than those of the ureters or vasa defe- rentia 5 and therefore need not be much surprised if -some physiologists, considering the time that the tubes take to perform their functions, considering the changes during that time in their sanguiferous and absorbent vessels, and their consequent changes in magnitude and form,.should thence be inclined te MOTlCfNS OF THE FEMALE ORGANS, &C. 56$ ascribe their motions to some other cause. I have only to observe, that things may exist without be- ing seen; and that though the evidence of sense be strong, it is not the only species of evidence on which we are warranted to rest our conclusions. The impregnated uterus continues to increase in its capacity till the time of parturition, though without a proportional diminution of thickness in its parities ; the thickness, in this case, being pre- served by a gradual increase in the length and di- ameter of its veins, its arteries, and its absorbents, which here undergo still greater changes than they ever are observed to undergo from natural causes, in either the ovaria or tubes of Fallopius, The enlargement of the vessels seems to be owing to a temporary growth, and to an additional mo- mentum of the blood ; while their tendency to contract, and resist that enlargement, may pro- Ibably, during the time of parturition, 5 assist the diaphragm, the abdominal muscles, and the ute- rine fibres in expelling the feet us. It is thus we explain how premature parturition is prevented by abstracting a part of the sariguiferous lluid, which during pregnancy, as d-uring coition, has more than ; an usual determination to the sexual organs. Nor are these changes in the sexual organs in conse- quence of the blood so very singular as one might at first be inclined to imagine : Every change in the state of the organs connected with the vital energy of the system, is preceded or accompanied N n a 564 MOTIONS OF THE FEMALE by changes correspondent in the state of its sels ; and these changes in the state of the vessels will be greater or less proportioned to the extent and continuance of the action performed by the organs. From the sudden, repeated, and evident con- tractions of the uterine fibres during parturition, we are naturally led to suppose that they are mus- cular. If they run not parallel, or radiate from a point, and form fasciculi, like the cameous fibres of most other muscles, they are certainly not more intricately interwoven than these forming the sep- tum of the heart ; if they be paler than the gene- rality of muscular fibres, they are not paler than those of the bladder ; if they gradually stretch for a number of months, and remain in a state of con- traction as long, the only difference in this respect between them and the fibres of many of the sphincters is, that the periods of contraction and relaxation are more prolonged. Previous to birth, the whole of the muscles, ex- cepting those of the vascular systems, remain in- active. For a number of months posterior to birth, the voluntary muscles contract and relax either for longer or shorter periods as the will directs ; the involuntary muscles, according to circumstan- ces over which the will has no direct influence, or, if times be limited, according to periods which are assigned by the Author of Nature ; and which periods we easily may suppose to be the periods ORGANS OF GENERATION. that are best suited to the nature of their structure, and to the general economy of the system. The only muscles which have been named and described by anatomists, as peculiar to the female organs of generation, are the Constrictor cunni, and Erectores clitoridis. The office of the first is implied in its name ; and the office of the second similar to that of the erecto- res penis. CHAP. XXI. MOTIONS OF THE SANGUIFEROUS SYSTEM. 1 HIS system has two sets of veins, the one pulmo- niC) and the other systemic ; two auricles belong- ing to the heart, the one pulmonic, and the other systemic ; two ventricles forming the heart, the one fulmonic, and the other systemic ; and two arteries issuing from the ventricles, the one puimomc, an4 $ie other systemic *. * See p. 231, 232, 568 MOTIONS OF THE The two sets of veins fill their auricles ; at the same time the two auricles, by asynchronous con r traction, fill their ventricles, when the two arteries, by a synchronous contraction, promote the circu jation through all their branches, and into the ex- treme branches of veins. These events, in ordi- nary cases, follow one another in the way and or- der in which they are enumerated; the only devi- ations from the general rule arising either from a morbid structure or inordinate action. When the auricles contract, the valves of the veins, the pressure on their sides, their conical form, the vis a tergo, and the momentum which the blood has acquired, conspire in resisting the retrograde motion ; while the free passage into the ventricles, and the relaxation of their muscular fibres, contribute to favour the progressive motion. When the ventricles contract, the case is diffe- rent : the passages backwards into the auricles arc comparatively large, the passages forward into the arteries comparatively small; the blood, besides, in passing to the arteries, is always resisted by a co- lumn of blood already in these vessels, and that resistance considerably increased by the conical form, and by the contractile power of the vessels, more apt to repel the blood to the heart, than to force it distad through their capillary branches. On these accounts, during the time that the ven- tricles are contracting, the passages between them and the auricles are shut by valves ; these valves, SANGUIFEROUS SYSTEM. 56? with the force of the blood pressing peripherad, making greater resistance to the lateral pressure produced by the ventricles, than the column of blood contained in the arteries. When the blood is forced into the arteries, their curvatures, near where they issue from the ventri- cles, are from their distension lengthened and ex- tended towards straight lines, and, causing the heart to participate in their motions, compel it to describe the segment of a circle, when the apex moving atlantad and sinistrad, is made to stnke against the left side. The same kind of motion having also been observed by the celebrated Hal* ler in distending the left or systemic auricle, it must follow, that the stroke which is given to the side may be the effect of two distinct causes, ei- ther acting separately or in combination, but act- ing on a heart, obliquely situated as ours is, in the cavity of the thorax, where the aspect of the base is atlantad and dextrad, and that of the apex sinistrad and sacrad. In combination, as the first of the two, by removing the pressure, will fa- cilitate the influx of the venous b]ood into the left or systemic auricle, which is situated dorsad ; so the second, by the influx of blood into the auricle, will contribute in its turn to facilitate the circular motion of the heart proceeding from the arteries. To prevent any reflux arising from that degree of resistance which the arteries oppose to the blood in the ventricles, there are three valves placed at the commencement of each of the two arterial 65 MOTIONS OF THE trunks, and the only valves to be found in whole arterial system. From the arteries being full when the ventricles contract, the additional blood which they receive necessarily dilates them ; and communicating an impulse, which is instantly felt through all their larger ramifications, propels, upon the recoil of the arteries, a proportional quantity through the distal extremities of the smaller branches * ; though at these extremities, the concentrated force arising from the impulse is so much diffused, that the blood apparently flows in a regular uniform stream, the effects of the impulse being too minute for the notice of the eye, and seldom perceived, excepting in cases of morbid sensibility. THE HEART. THAT the heart is capable, by its own exertions, of propelling the blood through the most distant branches of arteries, is probable from the cases where the arteries are ossified ; and probable, too, from the small force that is usually required in the art of injection : for to inject the systemic branches from the aorta, requires not a force greater than that which the heart is often known to exert, though greater than that for which it has usually any occasion. In one of the experiments of the accurate and very ingenious Hales, the pres* * See p, 227, 228, SANGUJFEROUS SYSTEM. sure of a column of warm water, four feet and a half perpendicular, was found sufficient, in the case of a dog, to impel the water from the aorta, and not only through all its capillary branches, but exhaling orifices. This learned writer, from his numerous experiments, was also of opinion, that three feet additional altitude would have forced the water in the same manner through the vessels of a man. From the comparatively greater facili- ty with which an injection flows through the arte- ries immediately after death, before the vital warmth has escaped, or the blood coagulated ; and from coarser injections, in these cases, returning sometimes even by the veins, it must be obvi- ous that many of the causes which usually pre- vent the success of injection did not exist in the living body. In the living body, the circulation already begun is only continued ; all the arteries are already full, all the communications are open; the blood is flowing in its customary channels, in channels purposely adapted for its use, and for which it had been purposely adapted ; nothing is omitted, nothing unforeseen, to promote circula- tion ; nothing is wanting in point of fluidity ; and nothing whatever is expected from the vessels that they had not performed a thousand times be- fore. In these circumstances, the .heart meets with only comparatively small resistance ; and hence the impulse which it gives to the blood is instantly felt through all the larger ramifications 3 57$ MOTIONS OF THE of the aorta. That this impulse is the principal cause of the motion of the blood, is not only pro* bable from the previous facts narrated above, but probable also from what we observe in a number f insects, where the want of every thing resem^ bling a heart, is accompanied also with the want of every thing resembling circulation ; and probable too from what we regularly observe in the foetus, where the circulation through the long and twisted umbilical cord is not performed by any particular structure of arteries, but by the combined force of the ventricles. THE ARTERIES. ARE we then to assert that the several arteries convey the blood merely as elastic inanimate tubes? Certainly net. We are neither prepared, nor are we willing, to make the assertion : For, though it may be granted that their different angles of ramification, their different convolutions, their different diameters, and their different modes of anatomising, can produce but effects that are merely mechanical in varying the force and velo- city of the blood ; yet many of the arteries have what we can demonstrate a fibrous structure ; a structure observed to contract and relax with the slighter changes of mental emotion, implying that they act from a vital energy ; while this \ital ener- gy, being differently exerted in difieient branches, SANGUIFEROUS SYSTEM. 71 if also a proof that different arteries are endowed with different irritabilities. All arteries are surrounded more or less with cellular substance ; beneath this substance, in the larger arteries, is a dense membrane called tunica ncrvosa ; beneath the tunica nervosa, again, are circular fibres, lying in a number of different stra- ta of a dusty colour, and in that respect having little resemblance to either the tendinous or car- neous fibres of the muscles which are known by distinct names ; beneath these strata of circular fibres, is the innermost coat, in contact with the blood, and smooth and lubricated on its central aspect. In addition to these different coats, some parts of the trunks, where they issue from the heart, receive a covering from the pericardium ; some a partial covering from the pleura, while they are in the thorax; and some likewise a par- tial covering from the peritoneum, while in the abdomen. Willis saw what he took to be glands in the coats of an artery belonging to an ox; and some have mentioned longitudinal fibres beneath the circular; but Albinus and Morgagni could see nekher in a human artery. All have seen the va- sa vasorum, the vessels intended for the nourish- ment of the coats. Many of the vasa probably terminate by exhaling orifices on the central as- pect of their veins and arteries ; and, by mixing their fluids with the currents within, may contri- ibute to change the qualities of the blood by a 57$ MOTIONS OF THE chemical process, as rapidly as either its force o? velocity are changed by the muscles. It is thus \ve are in part able to explain those sudden chan- ges in the qualities of the blood observed by Hew- son, in consequence of a change in the mental emotions ; and able to explain how some arteries are fitted to supply nourishment for bones, some for cartilages, some for muscles, some for tendons, some for ligaments, some for membranes, some for nerves, some for glands, and some for medulla and adipose matter ; but fitted to supply them by such a combination of chemical, mechanical, and vital action, that we cannot presume to define the limits that belong to each. For in pursuing these minute arcana of nature, the most learned and the most ingenious physiologists are but too apt to remind us of the poet, Whom often Fancy, ludicrous and wild, Soothed with a waking dream of houses, towers, Trees, churches, and strange visages expressed In the red cinders, while with poring eye Jie gazed, himself creating what he saw. With respect to the coats of the smaller arte* ries, whose structure eludes the most penetrating eye, some have imagined that they are analogous to thbse of the,, larger, and some have imagined that they are different. The late celebrated Mr John ^Hunter, finding by experiment that the trunks are more elastic than their branches, and fceing of oDinion that elasticity and muscularity \f SANGUIFEROUS SYSTEM. 573 arc riot only different, but belong to different clas- ses of fibres, concludes, that the circular fibres of the trunks and the larger branches are wholly e- lastic. Notwithstanding this opinion, having; shown by experiment, that all arteries are more elastic in the longitudinal than the transverse di- rection, he advances another, that the elastic fibres of arteries exert themselves chiefly in the longitu- dinal, and the muscular fibres in the transverse direction. Having somehow also satisfied himself that the elastic power of an artery was inversely as the muscular, he, in defiance of this inverse ra- tio, draws the singular inference, that they act as antagonists to one another ; and that when the muscular fibres of an artery happen to contract it beyond the middle state, it is the elastic power that restores it. From supposing, too, that the ef- fects of elasticity are immediate, while that of muscularity may be gradual he has concluded, that the contractions of the umbilical vessels, which had continued for two days, were the ef- fects of muscular fibres ; and as he believed that muscular fibres could act only from a vital ener- gy, he concludes again, that the muscles of the cord had continued to live for two days after their separation from the body. On the same prin- ciples, he might have concluded, that the liga- men turn Nuche of quadrupeds is muscular, and that its fibres in some cases continue to live not nly for two days, but a week, after all the vis- 574 MOTIONS OF TtfE cera of the cavities are extracted. With all defe- rence to this ingenious and celebrated author, he has not established a clear, marked, and general distinction between what is elastic and what is muscular. Gradual contraction is no proof that a substance is either vital or muscular. Some substances contract from heat, some from cold, some from dryness, and some from moisture ; nor is it any peculiar property of a muscular sub- stance to be inelastic, as every living muscular fibre, either from the mixture of cellular mem- brane, or some other cause, is more or less elastic. The muscular fibres in the stomach of an ox are very elastic after being boiled ; and the salted muscular fibres of ham continue elastic even for years. For these reasons, the elasticity of the cir- cular fibres in the coats of an artery, is no proof that they are not muscular; nor is their muscu- l;irity any proof that they will not contract from other causes than a nervous energy, though a fi- brous structure, with contraction arising from a nervous energy, be the characters that principally distinguish a muscle. Wherever arteries, or any other animal sub- stance, exhibit any thing like a fibrous structure ; wherever nerves can be traced oft these fibres ; and wherever these fibres can be shown to con- tract, from the direct and immediate action of a vital energy, I would have little hesitation in de- claring these fibres to be muscular 3 and conse- SANGUIFJEROUS SYSTEM. 573 qiiently little hesitation in declaring, that the cir- cular fibres, which are regularly seen in some of the larger arteries, are muscular : yet it will not follow, because some arteries have a muscular coat, that all arteries have a similar coat ; nor will it follow, that others are destitute of a muscular coat, because a muscular coat is not seen, or because their coats will not contract in consequence of the stimulants which we employ. We have reason to believe there are many fibres in the animal body which are too minute or too transparent even for microscopic observation, and even de- monstrative evidence, to believe that the nature of irritability is different not only in different species of organs, but in different parts of the same or- gans. Even the extensive contraction of a vessel, in consequence of stimulants applied to a part, is so far from demonstrating a muscular power, that it rather reminds us of the effects of irritability ia certain plants. The parts of the intestine con- tract separately and independently of one an- other ; and the only way in which we can stimu- late them to act together, is to stimulate all at the 'same time, either by direct application to all, or by an indirect influence on all, exerted through the medium of a vital principle. ' THE VEINS. THE veins exhibit no circular fibres, excepting a, part of the larger trunks towards the auricles, 576 MOTIONS OF THE where, in certain experiments, and in certain mals, Haller observed that they had a pulsation^ As this is the case, we can hardly expect to see circular fibres in the absorbents. Both veins and absorbents, however, are elastic as well as the ar- teries, and seem to contract from a vital energy ; though, where there is no fibrous structure, or at least no fibrous structure that is seen, we cannot decidedly pronounce them to be muscular. The contractile power of the vascular systems, how moderated. This power seems to be moderated partly by the fluids, which, either from their momentum or quantity, are calculated to dilate the different ves- sels in which they are flowing. It is moderated, too, by one part resisting another, as in the intes- tine, where the contractile power that is before, is made to resist, through the medium of the con- tents, the contractile power of the part that is be- hind. Auxiliary causes calculated to support or strengthen the action of the vascular systems. Towards the surface, the vessels, and the parts on which they are ramified, are affected not only by temperature and moisture, but by mental e- motions ; and if temperature and moisture some- times affect the mental emotions, the mental emo- tions affect in their turn the temperature and SANGUIFEKOUS SYSTJLM, 577 moisture not only on the surface, but towards the central parts of the system : And hence it is, that animal* have a power, to a certain extent, of ge- nerating heat, and of determining the circulating fluids to particular parts, in greater or less quan- tity and force as the feelings direct, or as circum- stances require. Gravitation and friction are well known to pro- mote circulation, while the action of the muscles, and the several parts surrounding the vessels, may accelerate so much, by their lateral action, the mo- tion of the fluids, that in many cases, as in violent exercise and phthisis pulmonalis, they throw the blood faster on the lungs than the lungs can dis- charge it by the most vigorous respiratory efforts. The effects of respiration on the motions of the blood are evident and constant in all the genera of warm-blooded animals. Nor do I here allude to effects by which the blood undergoes a change in the pulmonary vessels, nor to the effects arising from temperature, by which the fluidity of the blood is preserved. I allude to effects which are purely mechanical ; to those effects by which the lungs expand and collapse, by which the heart in the human body is regularly moved atlantad and sacrad, the mediastinum lengthened and shorten- ed, the pericardium stretched and relaxed, and the blood in a part of the cava i?ifefior accelerated or retarded by the actions of the diaphragm and abdominal muscles. Go 578 MOTIONS OF THE It is to these effects of respiration, and not to those imaginary muscles of the dura mater, that we owe the principal motions of the brain, which contribute so much to promote circulation in the cavity of the cranium. Haller has proved, that during expiration the blood accumulates, or is sometimes refluent, in the pulmonic auricle and veins, when the cerebral substance appears, to ex- pand, as it were, from the centre to the circumfe- rence ; and that, on the contrary, during inspira- tion, when the blood has a freer passage through the lungs, the same substance appears to subside on the lateral, inial, and glabellar aspects, towards the centre. Similar motions have been frequently observed after the operation of trepan, and might have been inferred from accumulations of blood in the face, when the respiration is a little sus- pended. These phenomena partly explain why the blood, in returning from the cerebral sub- stance, should pass through the sinuses of the dura mater* ; why the peripheral aspect of the cere- brum, and the central aspect of the pia mater, should present to one onother two surfaces so widely extended. By numerous minute ramifica- tions over these widely extended surfaces, the mo- mentum of the blood, and the size of the vessels, are so much diminished, that injuries, arising ei- * See p. 235. 236. 3 SANGUIFEROUS CANAL. 579 ther from increased momentum or quantity, are much resisted. At the same time, as the larger veins in which the accumulation takes place, are upon the peripheral aspect of the brain, or be- tween the convolutions of its cortical substance, the immediate effects will be chiefly confined to the parts near the surface; while the expansion of these parts, resisted by the cranium and du- ra mater, will recoil upon the parts towards the centre, and in some measure contribute to com- press them. The other motion which the brain seems to have, is what arises from the pulsation of its larger arteries ; and which, like the veins, are ramified chiefly towards the circumference or pe- ripheral aspect. Along the crura of the spinal marrow, the cir- culation is farther promoted by the inflections of the vertebral column, but is apt to be languid in cases of debility, when sometimes the blood accu- mulates so much in the venous sinuses as to occa- sion painful sensations, particularly towards the re- gion of the loins, where the inflections of the co- lumn had been greatest. Midst the last expirations previous to death, when the passage through the lungs is gradually, and at last totally obstructed, the pulmonic blood accumulates not only in its auricle and veins, but in the pulmonic ventricle and artery. Whence this ventricle in the dead body has very often thinner parietes and a larger cavity than the systemic, the Oo 2 580 MOTIONS OF THE SANGUIFEROUS CANAL. several branches belonging to the artery being al- so larger in their diameter than the veins which accompany them*. After death, the blood may sometimes continue to flow, independent of either the heart or the ar- teries. On opening the vessels of a dead body, we sometimes observe the blood rushing out, ac- companied with expansive bubbles of air ; and it is not improbable that bubbles of air, passing from the lungs into the aorta at the moment of death, or afterwards extricated by a chemical change, is one of the causes why some of the ar- teries are entirely empty, and others so nearly empty, after death. In these cases, as the blood cannot return to the heart on account of the valves, it is propelled by the particles of air towards the branches, when it either accumulates or enters the veins. That particles of air are ever extricated to promote the circulation in the living body, is what I would not presume to assert, though it be not improbable, that the air which is extricated within the intestine, contributes not unfrequently to assist that tube in propelling its contents. * See SaSatier, Premier Memoirs $ur PInegalc Capacity du Caur> et ds Vaisseaux Pulmonaires. INDEX, A ABDUCTOR brevis pollicis manus, attachments, page 197. func- tions, 408, 409 Abductor digit! minimi manus, attach. 199. func. 412, 414 digiti minimi pedis, attach. 207. fane. 453 indicis manus, attach. 193. func, 412, 413 longus pollicis manus, attach. 194. func. 409 pollicis pollicis pedis, attach. 210. func. 449, 452 Absorbents, 243 248. Commencing from the branches of the veins and arteries, probably vary the qualities of the blood by altering the proportions of its ingredients, 245* in the way of subtraction, as the vasa vasorum may alter the proportions of the same ingredients in the way of addition^ 57 l Accelerator urins, func. 556, 557 Adductor brevis femoris, attach. 203. func. 428430 longus femoris, attach. 203. func. 428 430 magnus femoris, attach. 203. func. 428 430 ossis metacarpi digiti aurieularis, attach. 190. fund 406 pollicis manus, attach. 197. func. 409 pollicis pedis, attach. 213. func. 452 Anconeus, attach. 190. func. 395 Anterior auriculas, attach. 169. func. 457 Antitragicus, func. 458 Arteries, 226 229. . Arteries and veins, 229, 243. No or- gans of the animal system more immediately under the in- fluence of vital energy, the nerves excepted, 243, 570 575 Arytsenoideus obliquus, attach. 499. func. 501, 502 transversus, attach. 499. func. 501. 502 Attitudes and motions of the trunk. The force and steadi- ness by which they are produced, are partly dependent on respiration, 355, 536 537 582 INDEX. Attoilens auricuTam, func. 457 Azygus uvulse, attach. 175, func. 507, 508 B Basio-glossus, attach, see Hyo-glossi, 177. func* 491, 492? Biceps brachii, attach. 186. func. 383, 384, 386, 394, 395, 398 crurfs, attach. 202. func. 428, 429, 430, 434, 437, 438 . Biveriter cervicis, attach. 180, 181 ; part of the complexus, func. 318, 321 maxillae, seu digastricus, attach. 165^. func. 3165 . 3'7 485* 49 6 499t505 Braclualis internus, attach. 190. func. 395 Buccinator, attach. 176. func. 462, 466 Carneous fibres, 2t8 Cerebellum, 249, 260, 261 Cerebrum, ibid. Cellular membrane, 224 225 Cerato-glossus, see Hyo-glossi, attach. 177. func. 491, 4921 Cervicalis descendens, attach. '79, func. 330, 332 Chondro-glossus, see Hyo-glossi, attach. 177. func. 491, 492 Circumflexus palati mollis, attach. 172. func. 508, 509 Cleido-mastoideus, part of the sterno-cleido-mastoideus, at- tach. 1 68. func. 318, 321, 323, 372, 515, 540, 541 Coccygeus, attach. 184, fuuc. 553, 554 Coccyx, 364366 Complexus, attach. 178. func. 318, 319, 321 Compressor naris, attach. 174. func. 466, 467 Compressor prostate, func. 556 Constrictor cunni, func. 565 pharyngis inferior, func. 504, 505 tuediuSj ibid, auperior, ibid. Coraco-brachialis, attach 188. func. 383, 386, 388 hyoideus, attach. 186. func. 496 Corrugator supercilii, attach. 168. func. 1 463, 464 Cremaster, func. 559 Crico-arytsnoideus lateralis, attach. 49:*. func. 501, 502 pusticus, attach. 498. func. 501, 502 INDEX. 583 Crico-tbyreoideus, attach. 498. func. 501, 562 Cruralis, attach, 294. func. 434 436 Cucullaris, attach. 170. func. 318, 3?!, 332, 345, 372, 377 Curvator coccygis, attach* 184. func. 553, 554 D Deltoides, attach. 188. func. 383 389 Depressor alse nasi, attach. 174. func. 466 anguli oris, attach. 176. func. 46^, 466 labii inferioris, attach. 176. func. 465, 466 Diaphragma, attach. 185, 521, 522, 528, 536, 537, 547, Epicranius, attach. 168. func. 462 464 Erector clitoridis, 565 penis, ^func.^58, 559 Extensor brevis digitorum pedi, attach. 206. func. 449, 45*453>454 communis digitorum raanus, attach. 198. func. 402, 403, 406, 407, 412, 413, 415, 416 longus digitorum pedis, attach. 214. func. 444, 445, 450, 453, 454 major pollicis manus, attach. 197. func. 398, 402, 408, 410, 411 minor pollicis manus, attach. 197. func. 403, 408, 410 proprius digiti auricularis, attach. 199. func. 41 2, 413 proprius pollicis pedis, attach. 218. func. 452 Externus mallei, attach. 170. func. 458 Flexor brevis digiti minimi pedis, attach. 215. func. 453 digitorum pedis, attach. 214. func. 449, 453, 454 pollicis manus, attach. 197. func. 409, 410 pollicis pedis, attach. 213. func. 449, 452 longus digitorum pedis, attach. 215. func. 444, 445, 45 3 454 pollicis manus, attach. 197. func. 403, 403 - 584 Flexor longus pollicis pedis, attach. 213. func. 445, 449* 452 Flexor parvus digiti minimi manus, attach. 199. func. 412, 413, where improperly named^fc#0r brews Functions of animals to be examined how, 272 Ganglions of nerves, 255 Gemellus, attach. 203- func. 434,437, 440, 444 446 Gemini, attach. 202. func, 428, 429 Genio-glossus, the genio-hyoglossus of Innes, attach. 176, func. 491, 492,494 Genio-hyoideus, attach. 176. func. 316, 496 Gluteus magnus, attach. 202. func. 370, 426430, 434 medius, attach. 202. func. 370, 426430 minor, seu parvus, attach. 202. func. 370,426430 Gracilis, attach. 201. func. 370, 426 430, 434, 438 H Heart, 565 570 Hyo-thyreoideus, seu thyro-hyoideus, attach. 177. func. 501 Iliacus interims, attach. 2OC, func. 370, 426 429 Indicator, attach 199. func. 402, 403, 412, 413 Jnfraspinatus, attach. 187. func. 383, 385, 386, 388, 389 Intercostales externi, attach. 184. func. 526, 528 534 interni, attach. 184. func. 526 534 Interossei externi digitorum manus, or anconal interossei, at- tach. 195, 196. func. ibid. 413, 414 externi digitorum pedis, attach. 210, 211. func. 453> 454 interni digitorum manus, or volar interossei, attach. 195, 196. func. 414 interni digitorum pedis, attach* 2IO, 2X1* func., 453* 454 Interspmales colh, attach 178.. func. 330 dovsi, attach. i8q>, 347 lumborum, func. 347 Intertransversarii dorsi, func. 342 583 tntertransversarii lumborum, func. 347 posteriores colli, func. 330, 331 priores colli, func. 330, 331 Irritability and life, 261 270 Latissimus colli, attach. 176. func. 316, 317, 320, 321, 462, 485 dorsi, attach. 188. func. 187, 345, 346, 370,384, Laxator tympani, attach. 170. func. 458 460 Left and right side ; differences between them, and effects of these differences, 239, 241 Levator anguli orls, attach. 174. func. 462, 465, 468 ani^ attach. 184. func. 553, 556, 557 labii superioris, attach. 174. func. 61, 62, 465, 46$ labii superioris alaeque nasi, attach. 174. func. 462, 465, 468 menti, attach. 176. func. 462, 465, 468 palati mollis, attach. 169. func. 508. 546 palpebrae superioris, attach. 172. func. 463 465 scapulae, attach. 186. func. 377, 380, 381 Levatores breviores costarum, seu supracostales breves, attach. 185. func. 515. longiores costarum, seu supracostales longi, attach. 184. func. 515 Lever, three kinds of, 277. Length of, to be estimated how, 278. Of the same muscle, lengthened and shortened, and how, 287, 289 Life and irritability, 261 270 Lingualis, func. 493 Longissimua dorsi, attach. 182. func. 343, 347, 360 Lougus colli, attach. 178. func. 320, 330, 332 Lumbricales manus, attach. 198. func. 407, 413415 pedis, attach. 214. func. 453, 455 M Major helicis, func. 457, 458 Masecter, attach. 176. func. 485, 487 489 Medulla oblongata, 248 250. Spinalis, ibid. Membrane, cellular, 224, 226 Minor helicis, func. 457, 45$ 586 INDEX. Multifidus spins*, attach, processus transversi et spinales cer- vicis, dorsi, lumborum, ossis sacri, et cristae iliorum, func. 33 343 347> 3^2, 363 Muscles, what, 217. Composed or carneous and tendinous fibres, cellular membrane, arteries, veins, absorbents, nerves, 218. Alive and irritable, ibid. Why they act by short le- vers, 279. Why a number of muscles surround those joints which admit of motion in various directions, 294, 295. Why the motions ofthe joints are made dependent on one an- other, and how, 295 297. Why some extend over seve- ral joints. 296, 297. Why some are called motors, some directors, some moderators, and some librators, 299 303 Mylo-hyoideus, attach. 177. func. 316, 485, 486, 496 N Nasales labii superioris, viewed by some as part of the levator labii superioris, attach. 174. func. 465, 466. Nerves, 24$. Of sense and voluntary motion, 249. Sensible, insensible, voluntary, and involuntary, 250253. Gan- glions of, 255. Plexuses of, 257 O Obliquus externus abdominis, attach. 185. func. 344, 348, 349 35 35 2 353 355357* 5 l6 522, 525, 535 553 554> 55^. How moderated by the muscles of the lips, isthmus faucium, and larynx, 53. 6 inferior capitis, attach. 179. func. 321, 322 oculi, attach. 174. func. 470, 471 internus abdominis, attach. 185. func, 344, 348, 340 352, 353> 355> 3.A 357, 516, 522, 526, 535> 553> 554> 55^ ^ ee Obliquus ext. abd. superior capitis, attach. 177. func. 313 315 oculi, attach. 172. func. 470, 471 Obturator externus, attach. 203. func. 427 430 internus, 'attach. 203. func. 427430 Opponens pollicis manus, attach. 194. func. 409 Qrbicularis oris, func. 462 465 palpebrarum, attach. 168. func. 462464 INDEX. 587 Palato-pharyngeus, seu tbyro-staphylinus, func. 507, 508 Palmaris brevis, func. 405 longus, attach. 189. func. 395, 398, 402, 405 Pectineus, attach. 203. func. 428, 429. Pe forms nearly the same office as the adductor brevis and longus ; but in some of tbe enumerations has been omitted. Pectoralia, attach. 188. func. 345, 347, 376, 383, 384, 386, 389,516 Peroneus brevis, attach. 205. func. 444, 445 longus, attach. 205. func 444, 445, 450 tertius, attach. 205. tune. 444, 445 Plantaris, attach. 203. func. 444, 445, 447 Plexuses of nerves, 257 Popliteus, attach. 203. func. 43*, 437 Profundus, attach. 190. func. 402, 405, 408, 413- 415 Pronator quadratus, attach, ulna and radius, improperly joined with the pronator teres (p. 191.) as originating in the humerus. func. 396398 teres, attach. 191. func. 39 $~ 398 Psoas magnus, attach. 203. func. 344, 347, 428, 429 parvus, attach. 181. func. 347 Pterygqideus externus, attach. 176. func. 485,487 489 internus, attach, 176. func. 485, 487, 488 Pyramidalts, attach. 201. func. 343, 3^4 Pyriformis, attach. 184. func. 428430 Q_ Quadratus femoris, attach. 202. func. 428 430 lumborum, attach. 200. func. 343, 347, 348, 516 R Radtalis externus longior ct brevior, attach. 189, 399, 401 4:6 internus, attach. 189. func. 395, 398, 402, 403, 406 Recti oculi, attach. 172. func. 469 472, 481 Rectus abdominis, attach, 2ci. func. 343, 347, 348, 352 355> 5 l6 5*9f 535> 553> 5J4 588 INDEX. Rectus crun's, attach. 201. func. 427. (should have been e. numerated among the flexors of the femur, 428.) 43 4 -743 6 > 43 8 m capitis internus major, attach. 171. fune. 318;, 3212. Should have followed the longi colli in p. 330. capitis internus minor, attach. 171. func. 313 315., capitis lateralis, attach. 171. func. 313 315. capitis posticus major, attach. 371. func. 318, 320, 3 21 capitis posticus minor, attach. 371. func. 313 Retrahentes auriculae, attach. 169. func. 457 Rhomboideus major, attach. 186. func. 345, 346, 376. Draws the base of the scapula* at. dor. mesi- ad, and should have been mentioned in p. minor, attach. 186. func. see Rhomboideus major. Right and left side, difference between them, and effects of these differences, 239 241 S Sacro-ltimbalis, attach. 182. func. 344, 347, 360, 362, 516 Salpingo-pharyngeus ; the pharyngeal fibres rising from the eaKiriy% O r Eustachian tube, func. 503, 504 Sartorius, attach. 200. func. 428 430, 434, 436, 438 Scalenus anticus, attach. 178. func, 330, 331, 515 medius, attach. 178. func. 330, 331, 515 posticus, attach. 178. func. 330, 331, 515 Semimembranosus, attach. 202. func. 427 430, 434, 437, Semispinalis dorsi, attach, 180. func. 343, 347 Semitendinosus, attach. 202. func. 428 430, 434, 436,438 Serratus anticus, attach. 186. func. 343, 346, 377, 378, 515 magnus, attach. 186. func. 343346, 347, 377, 380, 381, 515 posticus inferior, attach. 182. func. 344, 345, 5*6 posticus superior, attach. 180. func. 343, 347, 515 Soleus, attach. 204. func. 443, 445 Sphincter externus ani, func. 546, 553, 554, 556, 557 internus ani, see sphincter externus. Spinalls cervicis, seu semispinalis colli, attach. 178. func. 330, 332 Spinales dorsi, attach. 180. func. 343* 347 INDEX. 589 Splenius capitis, attach. 170. func. 318, 321, 332 colli, attach. 179. func. 330, 332 Stapedius, attach. 169. func. 458 460 Sterno-hyoideus, attach. 177. func. 317, 496, 546 Sterno-mastoideus, attach. 168. func. 318, 321, 323, 325* 33 2 37 2 5 J 5 54 Sterno-thyreoideus, func. 498, 501 Stylo-glossus, attach. 169. func. 491,494 Stylo-hyoideus, attach. 169. func. 496, 546 Stylo-pharyngeus, attach. 169. func. 504. omitted in the enumeration. Subclavius, attach. 186. func. 372, 515 Sublimis, attach. 189. func. 395, 398,402,403,405,413, 414 ; in 415. omitted as the flexor of the medial phalanx Subscapularis, attach. 188. func. 383, 388, 389 Supinator brevis, attach. 191. func. 398 Supinator longus, attach. 191. func. 395, 398 Supraspinatus, attach. 188. func. 383, 386, 388 Temporalis, attach. 169. func. 485, 487, 488 Tensor tympani, attach. 169, 170. func. 458, 459 Tensor vaginx femoris, Attach. 200. func. 428430, 434, Tendons, how shortened by carneous fibres, 276 Teres major, attach. 1 88. func. 383, 385, 389 minor, attach. 188. func. 383 385, 388 Thyreo-arytaenoideus, attach. 498. func. 501, 502 Tibialis anticus, attach. 204. func 444 posticus, attach 205. func. 445 Trachelo-mastoideus, attach. 168. func. 318, 321, omitted in 33 Tragicus, func. 457 Transversalis cervicis, attach. 179. func. 330 Transversus abdominis, attach. 200. func. 344, 348, 349* 352, 516, 553, 556. See Obliquus ext. abd. Transversus auriculae:, func. 457, 458 pedis, attach. 210. func. 449, 450, 452 perinaei, func. 556, 557 alter, ibid. Triangularis sterni, attach. 185. func. 516 Triceps brachii, attach. 190. func. 383, 385, 395 590 INDEX, u Vastus cxternus, attach. 203. func. 434 436 internus, attach. 203. func. 434 436 Veins, 229-243* 575 Vertebral column, curvatures or, 358- 362. Processes of, 361 Ulnaris externus, attach. 190. func. 403,406 internus, attach. 190. func. 395, 396, 402 gygomaticus major, attach. 173. func. 462, 465 minor, attach. 173. func. 462, 465 FINIS. EDINBURGH : Printed by JOHN BROW:T, ERRATA. Page 12. For " patabit," read "putabit." 21. For " internadii," read " internodii." 48. line 26. Dele " the." 49. For " spenoides," read " sphenoides." 169. For * sphenoidlea," read " sphenoidale." 205. For " tibiales postici," read " tibiahs postici.^ 22$. line 25. For " regions," read " organs." 336. line 19. Dele "it." 314. For "that when they happen to vary their forces", read, " that when they vary the proportions of their forces." 321. Dele " Directions." 330. For " 173," read 178." 460. For " stapidis," read " stapedis" ; for " stapidem," " stapedem ;" and for " sinis", " suus." $04, 505. in the notes. For " From", read " Form." OMITTED, 190. " Anconei," as extensors of the ulna. 185. After the COST.S; and their muscles, the OssA STERNI and their muscles, viz. the Recti abdominis, Transversi abdominis, Perforates^ Intercostales internt, Triangulates sterni, Sterno Sterno hyoidei, SttrnO'thyroidei 9 For their other attachments, see Index. 377. " Rhomboidei," as motors of the scapula, moving the base at. dor. mesiad. 415. " Sublimes," as flexors of the medial phalanx. 504, " Stylopharyngei," as constrictors of the pharynx. FOURTEEN DAY USE RETURN TO DESK FROM WHICH BORROWED Biology This book is due on the last date stamped below, or on the date to which renewed. Renewed books are subject to immediate recall. -9flf 1 6 1955 DEC 3 1955 j/ 1 .:: i 6 ! tfiJ7'59M$ OCT 30 1368 j* 96 a HRl