o 
 
GIFT OF 
 
 BIOLOGY 
 
A Balance-Chemograph 
 
 And the Excretion of Carbon Dioxide During Rest 
 
 and Work. 
 
 A Dissertation Submitted to the Faculty of the De- 
 partment of Literature, Science and the Arts 
 of the 
 
 UNIVERSITY OF MICHIGAN 
 
 In Partial Fulfillment of the Requirements for the 
 
 Degree of 
 
 DOCTOR OF PHILOSOPHY 
 
 fey 
 GEORGE OSWIN HIGLEY, M. S. '93 
 
 Instructor in Chemistry, University of Michigan 
 
 ANN ARBOR, MICHIGAN, 
 MAY, 1905 
 
A Balance-Chemograph 
 
 And the Excretion of Carbon Dioxide During Rest 
 
 and Work. 
 
 A Dissertation Submitted to the Faculty of the De- 
 
 partment of Literature, Science and the Arts 
 
 of the 
 
 UNIVERSITY OF MICHIGAN 
 
 In Partial Fulfillment of the Requirements for the 
 
 Degree of 
 
 DOCTOR OF PHILOSOPHY 
 
 GEORGE OSWIN HIGLEY, M. S. '93 
 
 Instructor in Chemistry, University of Michigan 
 
 ANN ARBOR, MICHIGAN, 
 MAY, 1905 
 
s 
 
 Preface 
 
 This work was done in the physiological laboratory of the Univer- 
 sity of Michigan. The writer desires to express his thanks to Profes- 
 sor Warren P. Lombard for his continued and active interest in this 
 research; to Professors S. L. Bigelow and Victor C. Vaughan for valu- 
 able suggestions; to Mr. W. P. Bowen in conjunction with whom the 
 work of Sections III., VI., and a portion of VII. was done; and finally 
 to friends who have so kindly served as subjects. 
 
 The work outlined in these papers was carried out with the Higley 
 and Bowen respiration apparatus described in an article published in 
 the American Journal of Physiology, Volume XII, 4, page 311. (1904.) 
 
TABLE OF CONTENTS 
 
 I. Introduction. 
 
 II. The Balance-chemograph. 
 
 1. Construction. 
 
 2. Tests. 
 
 3. Uses. 
 
 III. Methods of Determining the Rate of Excretion ol Carbon Di- 
 oxide from the Lungs. 
 
 1. Methods Previously Employed. 
 
 a. Respiratory Chamber Methods. 
 
 b. Mask and Mouth-piece Methods. 
 
 2. Method Employed in this Research. 
 
 IV. The Relation of Carbon Dioxide Excretion to Body Weight. 
 
 1. Introduction. 
 
 2. Method. 
 
 3. Results. 
 
 V. Influences which Modify the Rate of Carbon Dioxide Excre- 
 tion during Rest. 
 
 1. Introduction. 
 
 2. Method. 
 
 3. Results. 
 
 VI. The Excretion of Carbon Dioxide during Uniform Muscular 
 Work and its Relation to the Secondary Rise of the Pulse Rate. 
 
 1. Method. 
 
 2. Results. 
 
 VII. The Latent Period of Carbon Dioxide Excretion. 
 1. Method. 
 
 2 Results. 
 
 3. Conclusions. 
 General Summary. 
 
 293412 
 
A NEW CHEMOGRAPH AND SOME OF ITS PHYSIOLOGICAL 
 APPLICATIONS 
 
 1. Introduction. 
 
 The graphic method dates from the invention of the Kymograph 
 by Carl Ludwig in 1847. The superiority of this method over any meth- 
 od which involves the observing and recording of a series of phenome- 
 na by a single observer is obvious. "The graphic record includes more 
 than can be grasped by any observer no matter how well trained. The 
 records being preserved and read repeatedly, the chance of error is 
 greatly reduced. Time relations can be worked out on a graphic re- 
 cord with a precision which can not be approached by direct observa- 
 tion." Applied first in the study of the character of complex cardiac 
 and respiratory movements this method soon found numerous appli- 
 cations in the hands of the physiologist, the physicist and the engineer. 
 It was not until recently, however, that the chemist seriously turned 
 his attention toward a similar application of this method to a study 
 of the course of chemical reactions. 
 
 In 1899 Ostwald 1 , while engaged in an investigation of the re- 
 markable behavior of chromium towards acids, was led by the great ex- 
 penditure of time required to note at frequent intervals the indications of 
 a gasburette, to devise an apparatus which should record automatically 
 the rate of evolution of hydrogen . The gas was caused to flow from the 
 generator through a long capillary tube, a pressure thus being pro- 
 duced approximately proportional to the rate of evolution of the gas. 
 This pressure was caused to actuate a light lever by means of an ordi- 
 nary tambour, and the curve of rate of solution of the metal was thus 
 recorded upon a strip of paper. With this apparatus (the original 
 chemograph) Ostwald demonstrated the periodic character of .'he 
 chemical action; the effect upon the reaction of changes of temperature, 
 and of concentration of acid; the effect of numerous reagents on the pe- 
 riodicity of the action; and the synchronism of changes in the rate of 
 chemical action with those of the electrical tension of the metal. A 
 consideration of Ostwald's paper leads to the conviction that the graph- 
 ic method alone could have yielded such satisfactory results in the 
 study of a problem of this kind. 
 
 So far as the writer was aware when this research was begun, no 
 successful attempt had ever been made to determine the rate of a chem- 
 ical change by recording the movements of a balance beam. However, 
 in March, 1904, Professor G. N. Stewart, of Chicago University, while 
 examining the apparatus to be described in this paper, stated that he 
 had some time previously demonstrated the change in weight of a dialy- 
 zer filled with cane-sugar solution and suspended from the arm of a 
 balance in a solution of pure water. By means of a lever attached to 
 
the arm of the balance, a curve of change of weight of the dialyzer was 
 recorded upon a drum. Professor Stewart's paper was read at a meet- 
 ing of the Chemical Society of Owens College, Manchester, England, but 
 was published only by title. 
 
 The idea of securing a continuous record of the carbon dioxide ex- 
 haled from the lungs by recording the movement of a balance, was sug- 
 gested by Prof. W. P. Lombard as a possible means of explaining the 
 changes in the pulse rate resulting from muscular work. Bowen 2 had 
 found that in all vigorous work there are two well marked stages of 
 increase in pulse rate, which are often separated by a period of uni- 
 form rate. First, there is an immediate and rapid rise, the primary 
 rise, and later a more gradual secondary rise. The primary rise oc- 
 curs so promptly after the beginning of work (latent period .8 of a sec- 
 ond), that it could not be caused by the direct action of waste pro- 
 ducts on the heart centers. The secondary rise, however, which be- 
 gins, with the most vigorous work done in the research (852 Kilogram 
 metres per minute) one minute and twenty seconds after the beginning 
 of work, might have been caused by the direct inffuence upon the 
 heart of some waste product. The discovery of Loewy 3 that tartaric 
 acid, introduced into the jugular vein of an animal, markedly increas- 
 es the respiratory volume, seemed to indicate that acid waste products 
 thrown into the blood during the work might also be the cause of the 
 secondary rise in pulse rate noted by Bowen. One of these acid waste 
 products, carbon dioxide, was looked upon as a possible cause of the 
 phenomenon mentioned. It was, therefore, believed that a graphic re- 
 cord of the changes in rate of excretion of this substance, placed by the 
 side of the curve of the pulse rate- might throw light on the cause of 
 the change of the latter and could not fail to be of interest. 
 
 II. THE BALANCE-CHEMOGRAPH 
 
 *T;~. 
 
 1. Construction. 
 
 The apparatus for absorbing carbon dioxide and recording upon 
 a blackened paper its rate of flow, is constructed as follows: (Fig. 1, El- 
 evation). It consists of a Ruprecht lecture-room balance, capable of 
 carrying a load of 6 kilograms in each pan and of turning to 5 milli- 
 grams. To the beam there was attached a copper tube one and one- 
 half centimeters in diameter as shown by figure 2. Dry air contain- 
 ing carbon dioxide, enters at A through a short piece of very thin rub- 
 ber tubing made of a surgeon's finger cot, passes through the portion 
 designated by the arrows to the end of the beam and downward 
 through two rubber connections like that just mentioned, and a glass 
 tube D (Fig. 1) to the chamber for the absorption of carbon dioxide. 
 
 5 
 
FIGURE 1. This figure represents an elevation of thechemograph. The air enters at A 
 and takes the direction shown by the arrows. C is the absorbing apparatus, and C' 
 the counterpoise. Four gram-weights are placed upon the left beaker, and the lever- 
 points thereby deflected upwards on the drum (I). The curve of carbon dioxide ab- 
 sorbed in C, is written downward to the right upon the drum. 
 
 FIGURE 2. A horizontal section through the beam and balance tubes. The air passes 
 through those portions only which are designated by arrows. 
 
 suspended upon the arm of the balance. (C Fig 1.) From the ab- 
 sorption apparatus the air passes upward through similar connections 
 to the balance-tube C, back on the opposite side of the balance-beam 
 to the center, where it leaves the balance through another piece of rub- 
 ber tubing, and then passes into guard tubes G' and G", which will be 
 described later. 
 
 Absorption apparatus. (C, Fig 1). Several forms of absorption 
 apparatus have been used in connection with the chemograph. That 
 constructed for use in work experiments has been most employed and 
 will be described here. 
 
 Since there was a question of removing the carbon dioxide from 
 air flowing at the rate of 30 litres per minute during work, the absorp- 
 tion apparatus is necessarily large. It consists of a beaker 20 centi- 
 metres in diameter at the top, and 50 centimetres deep, with cover of 
 thin copper, provided with openings two centimetres in diameter, into 
 which are fitted the inlet and outlet tubes. The air passes downward 
 into the beaker through a thin glass tube 2 centimetres in diamoler, 
 
to within about 2 centimeters of the bottom of the beaker, ending In 
 an open space 3 centimeters deep and of a diameter equal to that of 
 the beaker. (This open space was left because it was thought that the 
 carbonic acid gas would thereby be more uniformly distributed through- 
 out the whole cross-section of absorbent placed above.) The air now 
 rises through about 5 kilograms of coarse, carefully screened soda-lime, 
 and then through glass-wool covered with phosphorus pentoxide to hold 
 back dust and the last trace of water formed in the reaction. This 
 beaker when charged weighs about 5% kilograms. It is counterpoised 
 by another beaker of the same exterior volume filled with spent soda- 
 lime. 
 
 Recording Apparatus. In order to record the movements of the 
 balance, there is attached to the end of the balance-beam a steel loop 
 which engages the short arm of the light lever (E, Fig 1), made of two 
 .straws placed side by side and tipped, at the short end, with a steel 
 wire, and at the long end with a piece of parchment paper. By meajis 
 of an arrangement (F, Fig. 1) which. will be clear from the figure, the 
 fulcrum of the lever may be adjusted vertically, transversely, and hor- 
 izontally. On the short arm of the recording lever (40 millimetres in 
 length) there is placed a movable weight, by an adjustment of which 
 the long arm (350 millimetres in length) is made to slightly preponder- 
 ate. The lever records upon the drum the movements of the balance- 
 beam magnified nine times. Since much depends upon the accurate ad- 
 justment of the writing lever upon the paper, the kymograph is set 
 upon a base provided with ball-bearings and with two springs working 
 against a screw, so that the kymograph may be rotated around a ver- 
 tical axis and thus the drum be quickly and accurately adjusted to the 
 recording lever at any time. Attached to the frame of the kymograph 
 is a vertical brass rod to which are clamped three slender brass springs 
 which extend horizontally and whose points may be brought into light 
 contact with the paper on the drum. The middle one marks the level 
 of the center of the fulcrum of the recording lever. This marker 
 when once adjusted is, of course, never disturbed. The upper and low- 
 er ones draw lines marking the upper and lower limits of the excur- 
 sion of the lever-point during calibration. They are readjusted from 
 time to time as may be necessary. 
 
 It has been already stated that the rubber connections of the bal- 
 ance were made very light in order to avoid, as far as possible, inter- 
 ference with the free movements of the balance. In order now to be 
 able to write a curve of considerable length, representing, for example, 
 a mass of five grams, it became necessary to diminish by some means 
 the sensibility of the balance while interfering, as little as possible, 
 with the uniformity of its movement. There was, therefore, attached 
 to the frame of the balance, about ten centimetres from the central 
 knife-edge, a steel yoke (H, Fig. 1) passing over the beam. From this 
 yoke there was suspended a coil, five centimetres in length and about 
 
one centimeter in Diameter, made of phosphor-bronze wire .83 millime- 
 tres in diameter. This coil was attached at its lower end to the upper 
 side of the beam of the balance by means of a hook, which together 
 with the yoke could be set at any desired distance from the central 
 knife-edge. A set screw, with a check-nut by which the upper end of 
 the coil is attached to the yoke, admits of an adjustment of the tension 
 of the spring at the will of the operator. 
 
 Adjustment of tension. The balance is brought into equilibrium 
 with spring disconnected. The spring is now attached to the beam 
 and brought into a state of tension by turning the screw at the upper 
 end of the coil, after which weights are placed upon the pan on the 
 same side until equilibrium is again restored. In most of the work 
 done with this apparatus the spring has had an initial tension of four 
 grams. 
 
 We have here a combination of the beam and the spring balance. 
 This apparatus was subjected to a series of careful tests in order to 
 ascertain whether the records inscribed by it upon the blackened pa- 
 per were of any value. 
 
 Tests of the balance: 1. Calibration. A careful test was made of 
 the amount of vertical deflection of the end of the recording lever on 
 the blackened drum produced by a mass of five grams. This was done 
 as follows: The balance was brought into equilibrium. The beam was 
 now arrested and five gram-weights were placed upon the counterpoise 
 beaker; this produced an angular deflection of the beam of about 1 de- 
 gree 45 minutes, and a vertical deflection of the recording lever-point 
 of about 73 millimetres. After a delay of about 30 seconds to allow 
 the lever to assume its position of rest, the screw controlling the posi- 
 tion of the drum was carefully turned until the blackened paper was 
 brought into light contact with the writing lever, and the kymograph 
 was started and allowed to run until a short horizontal line had been 
 drawn by the point of the recording lever upon the paper. The beam 
 was now arrested, the weights removed, the beam again released, and 
 the writing lever again allowed to come into a position of equilibrium. 
 The kymograph was now started as before and a second light horizon- 
 tal line drawn upon the paper. The vertical deflection of the writing 
 point is a measure of the mass of five grams. This process was repeat- 
 ed many times, the weight being alternately added and removed to 
 find out the accuracy with which the point of the writing lever returned 
 to the same level as the drum. It was found that at the beginning of 
 work, after the apparatus had stood for some hours, there was some 
 irregularity at the first two or three movements of the beam. However, 
 after a few minutes the movements became quite uniform. Starting, 
 now, from the highest position of the recording lever, the gram 
 weights were removed, one by one, the position of rest of the point of 
 the lever being marked at each step by a short horizontal line as in 
 the preceding case. 
 
X X 
 
 FIGXJRES 3A and 3B show the results of calibration of the chemograph with 5 gram- 
 weights. The distances XX' are the vertical deflections of the recording-lever point 
 for a mass of 5 grams added to the pan, The numbers represent the vertical deflec- 
 tion, in millimetres, of the lever point for ONE gram. A calibration of at least one 
 series is made at the beginning of each experiment and often at the close also. 
 
 TABLE I (A). 
 
 Millimetres. Millimetres. Millimetres. Millimetres. 
 
 Series I. Series II. Series III. Average. 
 
 Upper gram 15.4 15.1 14.7 15.06 
 
 Second gram 15.3 15.0 15.0 15.1 
 
 Third gram 15.2 15.3 14.7 15.1 
 
 Fourth gram 14.6 14.6 14.7 14.63 
 
 Fifth gram (14.2) (13.9) (13.3) 
 
 Total deflection . ..60.5 60.0 59.1 
 
 TABLE I (B). 
 
 Series I. Series II. Series III. Average. 
 
 Millimetres. Millimetres. Millimetres. Millimetres. 
 
 Upper gram 14.4 14.7 14.7 14.6 
 
 Second gram 15.1 14.8 15.0 15.03 
 
 Third gram 14.8 14.8 14.5 14.7 
 
 Fourth gram 14.7 14.6 14.5 . 14.6 
 
 Fifth gram ....(14.0) (14.5) (14.4) 
 
 Total deflection . ..59.0 58.9 58.7 
 
 Fig. 3 A and Table I A show the results of one of these calibrations 
 
 9 
 
in which are given the deflections due to one gram. Omitting the low- 
 er or fifth gram of each in A, we have the following averages. 15.06 
 15.1 15.1 14.6. The total deflection for four grams is, in the three 
 series, 60.5, 60, and 59.1 millimetres, respectively. The extreme varia- 
 tion in deflection for the four grams is 1.4 millimetres or 2.3 per cent, 
 and the greatest variation from the average of 0.7 millimetres, or 1.35 
 per cent. The greatest variation in deflection for a single gram (omit- 
 ting the lower or fifth gram in each series) is 0.8 millimetres or 5.2 per 
 cent.; the greatest variation from the average is 0.36 millimetres or 2.4 
 per cent. Figure 3 (B) and Table I (B) show the results of a calibra- 
 tion of the same apparatus, with slightly different tension in the spring. 
 In this case the greatest variation in deflections for 4 grams and 1 griim 
 are 0.3 millimetres or 0.5 per cent, and 0.6 millimetres or 4 per cent., 
 respectively, and the greatest variation from the average, 0.2 millime- 
 tres or 3.2 per cent., and .38 millimetres or 2.5 per cent. The results 
 of numerous calibrations shou ing that the deflection fcr the lower or 
 fifth gram invariably gives low values, the use of this portion of the arc 
 has been discontinued. 
 
 2. Test with a weighed quantity of mercury. A small crystall- 
 izing dish, previously weighed upon a fine balance, was placed upon 
 the right beaker, and the balance brought into equilibrium. Four gram 
 weights were now added to the left beaker and the point of the lever 
 thereby deflected vertically upward about 58 millimetres upon the 
 drum. The usual calibration with 4 grams having now been made, the 
 drum was started and a slow stream of mercury was allowed to flow 
 into the crystallizing dish from a simple apparatus with capillary de- 
 livery tube. There was thus described upon the drum a short horizon- 
 tal line, followed by a more or less regular curve inclining downward 
 toward the right. Finally when about two grams of mercury had be on 
 allowed to flow in this manner into the crystallizing dish, the addition 
 of mercury was discontinued, and the curve caused to end in a horizon- 
 tal line. The beam was now arrested and the crystallizing dish re- 
 moved. The vertical deflections of the writing lever due to the suc- 
 cessive addition and removal of four grams in the initial calibration 
 process were now determined. The average of these values is, of 
 course, the graphical equivalent of four grams. From this there waa 
 readily obtained the modulus of the balance, viz.: the number of milli- 
 grams represented by one millimetre of vertical distance upon the 
 drum. The vertical distance between the initial and final positions of 
 the writing lever in the experiment with mercury was now measured, 
 and the weight of mercury added obtained by multiplying the modulus 
 by this value. Finally the crystallizing dish with its contents was re- 
 weighed upon a fine balance, and the weight of mercury thus deter- 
 mined compared with that obtained by the graphical method. 
 
 10 
 
TABLE II. 
 
 Showing the results of calibration of Balance with Mercury. 
 
 Vertical 
 deflecti'n 
 for one 
 gram 
 
 * 
 
 Modulus 
 M 
 
 Initial 
 height of 
 writing 
 point 
 
 h. 
 
 Final 
 height 
 of 
 writing 
 point 
 rh' 
 
 Weight 
 graphi- 
 cally 
 deter- 
 mined 
 (h.h')M 
 
 Weight 
 on 
 fine 
 balance 
 
 Error 
 
 Per 
 cent. 
 Error 
 
 Millime- 
 tres 
 11.63 
 
 0.0859 
 
 Millime- 
 tres 
 82.5 
 
 Milli- 
 metres 
 55.9 
 
 2.287 
 
 2.273 
 
 + 0.014 
 
 + 0.61 
 
 11.63 
 
 0.0859 
 
 55.9 
 
 26.4 
 
 2.537 
 
 2.5695 
 
 0.0326 
 
 1.26 
 
 11.63 
 
 0.0859 
 
 83.0 
 
 58.5 
 
 2.148 
 
 2.1624 
 
 -0.0144 
 
 0.66 
 
 11.63 
 
 0.0859 
 
 58.5 
 
 34.6 
 
 2.055 
 
 2.0707 
 
 0.0152 
 
 0.70 
 
 14.57 
 
 0.0686 
 
 88.0 
 
 66.9 
 
 1.447 
 
 1.4331 
 
 +0.014 
 
 +0.98 
 
 14.57 
 
 0.0686 
 
 66.9 
 
 34.5 
 
 2.2237 
 
 2.2172 
 
 +0.0065 
 
 +0.29 
 
 14.57 
 
 0.0686 
 
 87.8 
 
 59.9 
 
 1,9149 
 
 1.9092 
 
 +0.0057 
 
 +0.3 
 
 14.57 
 
 0.0686 
 
 59.9 
 
 24.3 
 
 2.4434 
 
 2.4424 
 
 +0.001 
 
 +0.04 
 
 14.58 
 
 0.0686 
 
 88.0 
 
 76.0 
 
 0.823 
 
 0.847 
 
 0.024 
 
 2.8 
 
 14.59 
 
 0.0686 
 
 76.0 
 
 62.3 
 
 0.9396 
 
 0.9282 
 
 +0.0114 
 
 +1.23 
 
 14.59 
 
 0.0686 
 
 73.3 
 
 59.3 
 
 0.953 
 
 0,9488 
 
 +0.0031 
 
 +0.40 
 
 14.59 
 
 0.0686 
 
 59.3 
 
 42.7 
 
 1.139 
 
 1.177 
 
 0.0213 
 
 1.9 
 
 *Experiments 1-4 were made by the use of a brass spring; the fo! 1 owing experiments 
 with a phosphor-bronz spring of quite a different tension. This accounts for the widely 
 different values of the modulus. 
 
 The results of a series of such tests are shown in Table II, in 
 which there are given: Vertical deflection in millimetres of the lever- 
 point for one gram added to the pan: Modulus (M) or the weight in 
 grams corresponding to one millimetre deflection; initial height of 
 writing lever-point "h"; Final height of lever-point h'; weight of 
 mercury as graphically determined, (h-h') M; Weight of mercury as 
 determined on fine balance. Error + or , and per cent of error. It 
 will be observed that the error was generally positive, and varied in 
 the different experiments between .001 and .0326 grams, the average 
 error being about .014 grams, or approximately .7 per cent. 
 
 3. Test with uniform current of Carbon Dioxide. It will thus be 
 seen that the working of the chemograph is more uniform and accu- 
 rate when the weight is added gradually as in the case of the mercury 
 and without arresting the motion, that when the weights are added a 
 gram at a time with the necessary arrest of the beam. It was now 
 thought desirable to test the character of the curve written by the lever 
 as the result of a practically constant addition of weight to the absorp- 
 tion apparatus. Accordingly a current of carbon dioxide, as uniform as 
 possible, was caused to flow for even minutes through the apparatus, 
 the drum meanwhile revolving uniformly. The result was a smooth 
 
 11 
 
curve about 30 centimetres in length, which was a very close approxi- 
 mation to a straight line, measurements showing that at no point was 
 the deviation from a straight line greater than .7 millimeters. This 
 experiment was repeatedly performed with practically the same re- 
 sult. 
 
 It is evident that when the recording lever has reached the lower 
 limit of the arc, the beam may be arrested, and additional weights add- 
 ed without interrupting the experiment and with a loss of only a small 
 portion of the curve. This may be repeated for hours, enabling the op- 
 erator to determine both the course of the reaction throughout its whole 
 extent and the total weight of gas absorbed. 
 
 The method of determining the rate of the reaction during any pe- 
 riod is as follows: With a radius equal to the length of the long arm of 
 the recording lever, and with the proper points on the central reference 
 line as centres, arcs are drawn cutting the time line at the beginning 
 and the end of the desired period, and also the curve of carbon dioxide. 
 The vertical distance between the two intersections of the carbon-diox- 
 ide curve by these arcs is the measure of the amount of that gas ab- 
 sorbed during the time cut off below. The modulus of the apparatus 
 having been determined as described earlier, the rate of absorption be- 
 tween the desired limits is readily determined. 
 
 4. Test with a weighed quantity of carbon dioxide. A series of 
 experiments were now carried out with carbonic acid gas. There was 
 set up a carbon dioxide apparatus consisting of a small fractionating 
 flask provided with a dropping funnel and delivery tube, to which was 
 attached a drying tube filled with pumice stone and sulphuric acid. 
 Into this flask there was brought a quantity of a saturated solution of 
 sodium carbonate, while sulphuric acid was placed in the dropping fun- 
 nel. The apparatus was now carefully weighed, after which it was at- 
 tached to the drying tube of the chemograph, a current of pure air 
 free from carbon dioxide was drawn through it at the rate of half a 
 litre per minute, and the sulphuric acid was slowly dropped upon the 
 carbons *e. The gas thus produced, diluted with seven litres per min- 
 ute of purified outer air was drawn through the absorption apparatus 
 of the chemcgraph, the kymograph drum meanwhile revolving at a 
 uniform rate. This experiment was repeatedly tried, with the follow- 
 ing results. 
 
 No. Weight Carbon Dioxide. 
 
 By Loss in Weight. Graphically. Error. Per Cent Error. 
 
 1. 2.4 2.33 .07 2.9 
 
 2. 3.548 3.487 .061 1.7 
 
 3. 1.810 1.815 .004 0.03 
 
 4. 2.933 2.83 .103 3.5 
 
 5. 3.152 3.192 .040 1.2 
 
 12 
 
3 Uses. 
 
 It is evident that this form of chemograph may be used in a study 
 of the course of many chemical reactions in which gas or vapor is 
 evolved, since the apparatus will evidently write a curve of loss in 
 weight as readily as of gain in weight. It is only necessary to pTace 
 the generator upon the pan of the balance, to make the usual adjust- 
 ments, and allow the process to continue as long as desired. A tracing 
 of the course of a reaction in which there is an escape of hydrogen 
 will, perhaps not be practicable with this apparatus, on account of the 
 lightness of that gas. However, the curves of rate of loss of water, 
 ammonia, carbon dioxide, etc., may be readily written. 
 
 III. METHODS OF DETERMINING THE RATE OF EXCRETION 
 OF CARBON DIOXIDE FROM THE LUNGS. 
 
 1. Methods Previously Employed. 
 
 A great variety of methods have been employed by different investi- 
 gators to determine the rate of excretion of carbon dioxide from the 
 lungs. The methods are of two types: Respiratory Chamber Meth- 
 ods and Mask or Mouth Piece Methods. 
 
 a. Respiratory Chamber Methods. 
 
 The earliest form of respiratory chamber was a simple bell jar in 
 which a small animal was confined, in some cases until asphyxiation 
 resulted. Samples of the inclosed air were taken, as desired during 
 the course of the experiment and at its close, and analyzed for carbon 
 dioxide and oxygen. Such a method was made use of by Black 4 . 
 Priestly 5 Lavoisier and La Place 6 , r-nd others. It has recently been 
 successfully employed by Haldane and Smith 6 in a study of the ques- 
 tion of existence of odorous sutstances in the air exhaled by a human 
 subject. This method is, of course, open to the objection that there 
 is a constant diminution in the amount of oxygen present in the cham- 
 ber, and a correspcnding increase in respiration products v.ith dis- 
 turbance of the normal respiratory exchange. In order to remove the 
 objectionable features of this primitive apparatus, Lavoisier suggested 
 two improvements which resulted in the development of two distinct 
 forms of respiratory chamber which are in use at the present time. In 
 the first form, that of Regnault and Reiset, the air of the chamber is 
 circulated by means of pumps through a system of purifying tubes 
 charged with concentrated sulphuric acid and with potassium Hydrox- 
 ide for the removal of water and carbon dioxide respectively; the oxy- 
 gen is brought up to the normal amount by addition of a fresh supply 
 from a gasometer and the air returned to the chamber. This apparatus 
 has been employed in a modified form by Hoppe-Seyler and Stroganow' 
 Pfluger and Colesanti 8 . and Atwater and Benedict 9 . 
 
 Lavosier's second modification WP.S developed by Scharling 10 . An 
 animal was placed in a chamber consisting of a large cask, provid- 
 
 13 
 
ed with inlet and outlet tubes. Air freed from carbon dioxide was 
 drawn through the chamber, the moisture and carbon dioxide in the 
 out-going air being absorbed by concentrated sulphuric acid and po- 
 tassium hydroxide respectively. Samples of the air in the cask at the 
 beginning and the end of the experiment were also taken and analyzed. 
 
 Since it w^as found difficult to maintain a sufficient ventilation and 
 at at the same time to secure complete absorption of carbon dioxide and 
 water, Pettenkofer 11 modified this apparatus in the following man- 
 ner: The total volume of air drawn through the chamber was deter- 
 mined by means of a meter. Continuous samples of the air entering 
 and leaving the chamber were also taken, measured, and analyzed for 
 carbon dioxide and water; the difference in the content of carbon diox- 
 ide and w r ater in the two sample's multiplied by the ratio of the total 
 ventilation to the volume of the samples, gave the amount of carbon di- 
 oxide and water exhaled by the subject. 
 
 Pettenkofer's apparatus was further improved by Tigerstedt 12 , 
 was given a capacity of 100 cubic metres, and has since been extensive- 
 ly employed by Johannsen 13 , Atwater and others. This apparatus 
 has many points of excellence some of which are as follows: 
 
 (1) It admits of experiments of indefinite length. 
 
 (2) It admits of making experiments upon eighteen or more per- 
 sons at once, thus enabling the experimenter to obtain average values. 
 
 (3 In its most complete form as employed by Atwater 14 , it 
 performs the w r ork both of a respiration apparatus proper and of a ca- 
 lorimeter, giving results which are comparable in accuracy to those ob- 
 tained by the use of the combustion calorimeter and the combustion 
 furnace. 
 
 Quite recently there has appeared a respiratory chamber method 
 by Jacquet 15 . In respect to capacity of chamber there is here a de- 
 parture from modern methods, as it holds only two or three cubic me- 
 ters. However, the samples of air, taken at intervals of one hour, are 
 collected over mercury, and analyzed by the very accurate Petterson 
 and Hogland method thus permitting a determination of oxygen as 
 well as carbon dioxide. 
 
 (b) Mask and Mouthpiece Methods: 
 
 The first quantitative study of the respiration was made with the 
 Mask method by Lavoisier 16 . This investigator in 1790, read, before 
 the French academy, a paper in which a new method was described. 
 The subject wore a mask (tete du cuivre) connected with a gasometer 
 containing air. This air after passing into the lungs of the subject 
 was exhaled through a huge tube filled with caustic potash solution, 
 the increase in weight of which represented the carbon dioxide. 
 
 Method of Speck 17 . According to this method the subject, with 
 closed nostrils, breathes through a mouth-piece from a spirometer, 
 the air being collected in a second spirometer. At the close of the ex- 
 periment a sample of air is drawn from the expiration spirometer and 
 
 14 
 
its percentage of carbon dioxide and of oxygen determined by absorp- 
 tion with barium hydroxide and pyrogallol respectively. 
 
 Method of Geppert and Zuntz 18 . According to this method the 
 expired air is forced through a carefully calibrated gas meter and its 
 volume accurately measured. Samples of the air are taken by means 
 oi a special sampling device which is operated by the gas-meter itself. 
 A number of tubes each with a capillary at the upper end, are filled to 
 the tips with acid water. These are connected to a lowering device 
 which is driven by a belt running over a pulley on the main axis of 
 the gas-meter. As the air passes through the gas-meter the pulley re- 
 volves, the leveling tube connected with the collecting apparatus is 
 gradually lowered and the collecting tube is thus filled with air, whose 
 composition has been found to represent quite accurately that of the 
 air passing through the meter. These samples of air are then analyzed 
 for carbon dioxide and oxygen, and there is thus obtained both the car- 
 bo ndioxide excreted and the oxygen absorbed, giving, of course, the 
 respiratory quotient. 
 
 Method of Hanriot and Richet 19 . The method of these investiga- 
 tors is beautiful in principle. The outside air is drawn through an ac- 
 curately caibrated gas-meter, is then inspired by the subject and ex- 
 pired through a second gas-meter. It now passes through an absorp- 
 tion apparatus charged with concentrated potassium hydroxide solu- 
 tion which dissolves the carbon dioxide, after which it is measured by 
 a third gas-meter. If v represents the volume of inspired air, v 1 that of 
 the expired air, and v" that of the expired air deprived of carbon di- 
 oxide, it is evident that v 1 minus v 11 represents the volume of carbon 
 dioxide excreted, and v minus v 11 represents the volume of oxygen 
 absorbed. 
 
 2. Method Employed in This Research. 
 
 Each of the methods outlined above has its excellent features and 
 has contributed to our knoweldge of the respiration process; however, 
 as a careful study showed no one of them to be adapted to a determin- 
 ation of the rate of change of carbon dioxide excretion, within short 
 intervals of time, such as was demanded in this research, Mr. "W. P. 
 Bowen and the writer 20 devised the apparatus now to be described. 
 
 The subject breathes through a mask with valve-chamber for the 
 separation of the inspired and expired air. The latter is dried by 
 means of sulphuric acid, and is then freed from carbon dioxide by pass- 
 ing through the chemograph as described in a preceding section. The 
 air now passes in succession through two guard-tubes and a gasometer 
 and to a suction pump. The apparatus, which with the exception of 
 mask, chemograph and pump, is shown in figure 4, is constructed in 
 the following manner: 
 
 Mask. The subject respires through a mask made as follows: A 
 
 15 
 
copper wire 2 millimetres in diameter is so bent as to fit over the 
 bridge of the nose and the face, inclosing nose and mouth. A piece of 
 heavy tin is then bent in the same form, that of an ovoid about 11 cen- 
 timetres in length and 8 centimetres broad at the widest part. This 
 is soldered to the wire, making the sides of a box about 4 centimetres 
 in depth and rather closely fitting the face. The space between this 
 edge and the face, is made air-tight in the following manner: A rubber 
 tube, such as is used on the Townshend ether inhaler, is stretched on 
 over the wired edge and fastened with cement. By inflating the tube 
 and closing it off by means of a clamp, a cushion filled with air is 
 brought between the face and the wired edge of the mouth piece. A 
 sheet of rubber is stretched over the front of the box, and firmly ce- 
 mented and wired in place. This is then pierced in the center and 
 through it passes a short glass tube 1.2 centimeters in diameter, which 
 is attached to the valve-chamber. Especial care was taken to make 
 the volume of the tubes between the mouth and the valves as small as 
 possible. The mask is held firmly to the face by wide elastic bands 
 passing around the head. 
 
 Valve-chamber: (V, Fig. 4). The valve-chamber is of the same 
 general form as that used by Zuntz and S'chumburg", except that it 
 is made of glass instead of metal, thus permitting a view of the work- 
 ing of the valves. It consists of a large T tube, 20 centimetres in length 
 and 4 centimetres in diameter, with a side tube 1.2 centimetres in di- 
 ameter, to which the mouth piece is attached. The valve seats are 
 
 JFf] 
 
 FIGURE 4. The respiration apparatus except ni'sk, chemograph and pump. Out-door 
 air eaters at O. R is the bag. The dryiag apparatus and guard tube are shown at 
 G. A and B connect with the tubes of the chemograph T is an auxiliary tube with 
 adjustable valve, by means of which the flow of air through the main circuit may 
 be regulated. 
 
 16 
 
of cork covered with thin sheet-rubber fastened on with rubber ce- 
 ment. The openings are about 1.5 centimetres in diameter; the valves 
 are made of thin sheet-rubber stiffened above with a disk of very thin 
 aluminum foil attached by means of rubber cement. The out-door air 
 enters the lower end of the valve-chamber through a wide glass tube. 
 (0). 
 
 From the valve-chamber the air passes into a rubber balloon hold- 
 ing when moderately distended about 3 litres. At each expiration this 
 balloon is somewhat inflated, but is deflated through the chcmograph 
 by the action of the pump during the next inspiration. There is thus 
 a substantially uniform delivery of air to the chemograph. 
 
 It is often convenient to cause the expired air to pass for a time di- 
 rectly to the pump without passing through the chemograph. For this 
 purpose a shunt is introduced in the main circuit beyond the balloon. 
 
 Drying Tubes. The apparatus for the removal of moisture con- 
 sists, essentially, of a U tube 75 centimetres in length and 4 centimetres 
 interior diameter, filled with coarse pumice stone saturated with con- 
 centrated sulphuric acid. This tube is followed by a guard tube (G Fig. 
 4), about 25 centimetres long, filled in the same manner. The com- 
 pleteness of the action of the preceding tube may be seen in the fact 
 that the guard tube in no case gained more than .01 grams, and usually 
 less than ,005 grams, during an experiment in which air saturated 
 with water vapor, and flowing at the rate of 30 litres per minute, pass- 
 ed through the train for 30 minutes. 
 
 From the guard tube the air flows through the absorption beaker 
 of the chemograph, passing then through two guard tubes G' and 
 G" filled with pumice stone and sulphuric acid. The first of these 
 tubes in an ordinary work experiment shows a gain of only .05 grams; 
 the weight of the second remains practically unchanged. The air pass- 
 es now, at the will of the operator, through a shunt tube containing 
 clear lime-water as a test for the presence of carbon dioxide, then 
 through an Elster gas-meter and to the pump. 
 
 Suction Pump. In order to relieve the lungs of the subject from 
 the labor involved in forcing the expired air through the tubes and gas- 
 meter, the latter is connected to the suction side of a number 2 Amer- 
 ican blower, capable of drawing air through the entire apparatus at 
 the rate of 30 litres per minute. This amount of air is sufficient for a 
 subject engaged in moderate muscular work, but its rate of flow is not 
 equal to that at which air passes trom the lungs during a vigorous act 
 of expiration. The balloon previously mentioned is introduced in the 
 circuit in order to permit the subject to exhale freely, the air expelled 
 at one expiration being drawn from the balloon by the pump during 
 the next inspiration. 
 
 It has already been stated that the suction pump is capable of 
 drawing 30 litres of air per minute through the respiration apparatus. 
 Since, however, in rest experiments the subject needs only 6 to 8 litres 
 
 17 
 
of air per minute, some system of regulation was needed whereby the 
 amount of air drawn through the apparatus could be adjusted at will. 
 There was therefore introduced above the gasmeter a side tube (T Pig. 
 4) provided with an adjustable valve. When this valve is closed there 
 is drawn through the train the amount of 30 litres per minute; when 
 the valve is open the resistence of the short side tube is so slight that 
 little or no air passes through the train. The handle of the valve pass- 
 es over a graduated arc. A preliminary calibration process enables 
 the operator to so set the valve that any desired volume of air up to 30 
 litres per minute will pass through the train. 
 
 Some of the advantages claimed for this respiration apparatus are 
 the following: 
 
 (1) As a result of the excellent fit of the mask and of the relief 
 afforded to the respiratory organs by the combination of balloon and 
 suction pump, the conditions approach very closely to those of normal 
 respiration. In fact, it has several times happened that a subject has 
 fallen asleep during a rest experiment, after the mask had remained 
 continuously upon the face for from one to three hours. 
 
 (2) This method permits of a determination of the carbon dioxide 
 excreted during normal respiration within 2 per cent. 
 
 (3) This method obviates the necessity of taking samples of the 
 expired air, and of making long and tedious analyses followed by com- 
 plicated calculations. At the close of an experiment lasting an hour 
 or more the total weight of carbon dioxide excreted by the subject may 
 be. ascertained in five minutes or less. 
 
 (4) By reason of the capacity of the chemograph to register 
 changes in rate of absorption of carbon dioxide, the whole course of ex- 
 cretion can be determined. 
 
 IV. THE RELATION OF CARBON DIOXIDE EXCRETION TO 
 BODY WEIGHT. 
 
 1. Introduction. 
 
 Considerable work has already been done in this field by Zuntz" 
 Johanssen 23 , Magnus-Levy 24 , Tigerstedt and Sonden 25 and others. 
 The average results given in the form of carbon dioxide excretion per 
 kilogram of body weight per minute are widely variable, as will appear 
 by reference to Table III. 
 
 18 
 
TABLE III. 
 Showing the Relation of Carbon Dioxide Excretion to Body Weight. 
 
 Carbon Dioxide 
 
 Conditions of Experiment. - Excretion Observer, 
 
 Grams per Kilogram 
 and minute. 
 
 1. Complete rest in bed; average for 24 
 
 hours 0048 Johansson. 
 
 2. Complete rest, sitting; average for 24 
 
 hours 00516 Johansson. 
 
 3. Complete muscular rest 00512 1 
 
 .00484 j Zuntz ' 
 
 4. Ordinary rest in bed, average for 24 
 
 hours 00578 Johansson. 
 
 5. Complete muscular rest reclining 
 
 from 9:35 a. m. to 7:21 a. m 0058 Magnus-Levy. 
 
 6. Complete muscular rest, fasting 00594 Magnus-Levy. 
 
 7. Nine persons sitting quietly, 10 a. m. Tigerstedt 
 until 3 p. m .00792 and Sonden. 
 
 8. Five persons doing no muscular work; Tigerstedt 
 average fasting value 00756 and Sonden. 
 
 9. Nineteen persons muscular rest, reclin- 
 ing, 3:20 to 5:30 p. m..: .0063 Higley. 
 
 These variations arise partly because the subjects during the ex- 
 periments were in different degrees of muscular rest, and partly be- 
 cause the experiments were made at various lengths of time after 
 meals, thus involving the variable work of the digestive organs. The 
 great difference between the carbon dioxide excretion during absolute 
 rest and during merely relative rest has been well shown by Johanssen. 
 These experiments in which Johanssen himself, was the subject, were in 
 part carried out while the subject was in the state or ordinary rest 
 in bed and in part while all muscular tension was avoided as far as 
 possible. In the former experiments the average carbon dioxide ex- 
 cretion per kilogram of body weight per minute was .0059 grams; in 
 the latter series the average was only .0054 grams, a difference of 8.6 
 per cent. The posture of the subject also has a great influence on the 
 intensity of the gaseous exchange. Thus Johanssen found the carbon 
 dioxide excretion while the subject was sitting, to be 1.5 grams per 
 hour more than while he was reclining, a difference of 7%. Katzen- 
 stein has observed, in parallel work, a difference of from 12 to 22% 
 for this difference of posture. 
 
20 
 
The experiments of Vierordt 26 , Speck 27 , and others have sho\vn 
 that the rate of excretion of carbon dioxide is increased 40 per cent as a 
 result of the digestion process. This increase is attributed to the in- 
 crease of work of the body due to the increased activity of the digestive 
 organs, and also in part to conversion of carbohydrates into fats 
 with separation of a large percentage of the oxygen of the former as 
 carbon dioxide (Hanriot 2S ). From these results it follows that a uni- 
 form rate of excretion of carbon dioxide per kilogram of body weight 
 in the case of a number of subjects or even with the same subject can 
 not be expected, unless the experiments are carried out at approximate- 
 ly the same hour, and at about the same length of time after a meal 
 which is approximately the same as to amount and character. 
 
 A number of persons, mainly medical students, having volunteered 
 to act as subjects, the writer carried out experiments on the rate of 
 excretion of carbon dioxide per kilogram of body weight. 
 
 It is not claimed that the experiments now to be described wero 
 carried out in an ideal manner, since the subjects were under the con- 
 trol of the experimenter only during the 20 minutes immediately pre- 
 ceding the experiment. Furthermore, in most cases the subjects had 
 had no previous experience in similar work. However, the experi- 
 ments were carried out at approximately the same time of day, the 
 subjects partook of their midday meal at about the same hour, and the 
 work of the subjects was about the same during the hours that inter- 
 vened between the meal and the experiment. The subjects were engag- 
 ed for the most part in Physiological laboratory work during the 
 hours that intervened between the pj eceding meal and the experiment. 
 All the subjects were apparently in good health except that two were 
 troubled at the time with indigestion and two had colds. 
 
 (2) Method. The experiments were conducted as follows: Each 
 subject in turn reclined upon a couch for about 15 minutes preceding 
 the beginning of the work. The mask was now adjusted and, at the 
 end of a further period of 5 m'nutes the experiment began. Great 
 pains were taken that the subject should be in a state of as complete 
 muscular rest as possible. 
 
 (3) Results. The results are shown in table IV in which are giv- 
 en: sex; age; weight of subject (exclusive of clothing) in pounds and 
 kilograms; date; time elapsed since preceding meal; length of experi- 
 ment; carbon dioxide excretion in grams per minute, and in grams per 
 minute per kilogram of body weight; remarks. 
 
 11 
 
TABLE IV. 
 Table Showing Relation of Body Weight to Carbon Dioxide Excre- 
 
 tion: 
 
 No 
 
 Weight 
 without 
 . Sex Age Clothing Date 
 
 Ibs Kilos Mo. Day Hr. 
 
 Time H,ength Carbon PerMin. & 
 Since of Ex- Dioxide Kilo Body 
 Preced perim't Excretion Weight Remarks 
 ing Minut's Per Min. Grams. 
 Meal Grams. 
 
 1 
 
 M 
 
 23 
 
 135 
 
 61 5 
 
 3 7 
 
 3 50 
 
 3.5hrs. 10 
 
 .400 
 
 0065 
 
 
 2 
 
 M 
 
 
 167 
 
 76 
 
 3 7 
 
 4.20 
 
 4 
 
 10 
 
 393 
 
 .0056 
 
 Adipose tissue 
 
 3 
 
 M 
 
 20 
 
 137 
 
 62-2 
 
 3 9 
 
 4-40 
 
 4 25 
 
 10 
 
 377 
 
 C06 
 
 
 4 
 
 M 
 
 20 
 
 
 
 3 9 
 
 5-00 
 
 4-75 
 
 10 
 
 -348 
 
 
 
 5 
 
 M 
 
 21 
 
 137 
 
 62-2 
 
 3 14 
 
 4.00 
 
 4 
 
 6 
 
 -410 
 
 0065 
 
 
 6 
 
 M 
 
 20 
 
 126 
 
 57-3 
 
 3 14 
 
 4-20 
 
 4 
 
 7 
 
 .420 
 
 0073 
 
 
 7 
 
 M 
 
 20 
 
 139 
 
 63-2 
 
 3 14 
 
 5-20 
 
 5 
 
 7 
 
 417 
 
 (.0066) 
 
 Catarrh infec'n 
 
 8 
 
 F 
 
 30 
 
 107 
 
 49 
 
 3 16 
 
 4.15 
 
 4 
 
 8 
 
 .297 
 
 006 
 
 
 9 
 
 F 
 
 19 
 
 112 
 
 51 
 
 3 16 
 
 4.45 
 
 4.5 
 
 6 
 
 .341 
 
 .0067 
 
 
 10 
 
 F 
 
 30 
 
 176 
 
 580 
 
 3 16 
 
 5 30 
 
 5-20 
 
 6 
 
 .442 
 
 -0'>55 
 
 Adipose tissue 
 
 11 
 
 M 
 
 20 
 
 33 
 
 60.2 
 
 3 18 
 
 4.00 
 
 3-75 
 
 4 
 
 -366 
 
 0061 
 
 
 12 
 
 M 
 
 21 
 
 115 
 
 52-3 
 
 3 18 
 
 4-15 
 
 4 
 
 3 
 
 .283 
 
 -0054 
 
 
 13 
 
 M 
 
 22 
 
 145 
 
 66 
 
 3 18 
 
 4.30 
 
 4 
 
 5 
 
 .503 
 
 (.0076) 
 
 Nausea 
 
 14 
 
 M 
 
 21 
 
 162 
 
 73-6 
 
 3 19 
 
 3-20 
 
 3 
 
 6 
 
 .465 
 
 .0063 
 
 
 15 
 
 M 
 
 27 
 
 190 
 
 86.4 
 
 3 19 
 
 3-20 
 
 3-5 
 
 5 
 
 -552 
 
 .0064 
 
 
 16 
 
 M 
 
 22 
 
 129 
 
 58 
 
 3 19 
 
 4-00 
 
 3 
 
 5 
 
 .368 
 
 .0063 
 
 
 17 
 
 M 
 
 25 
 
 15* 
 
 71-6 
 
 3 19 
 
 4.00 
 
 3-5 
 
 = 
 
 549 
 
 .0076 
 
 
 18 
 
 M 
 
 24 
 
 135 
 
 561.2 
 
 3 21 
 
 3-50 
 
 3-5 
 
 5 
 
 .376 
 
 0061 
 
 
 19 
 
 M 
 
 26 
 
 154 
 
 570 
 
 3 21 
 
 4.00 
 
 3-5 
 
 7 
 
 -463 
 
 (.00f6) 
 
 Slight nausea 
 
 20 
 
 M 
 
 26 
 
 1x4 
 
 8?. 9 
 
 3 21 
 
 4-35 
 
 4.25 
 
 5 
 
 .583 
 
 .0069 
 
 Athlete 
 
 21 
 
 M 
 
 21 
 
 139 
 
 63-1 
 
 3 21 
 
 5-00 
 
 4 5 
 
 4 
 
 .458 
 
 .0073 
 
 
 22 
 
 M 
 
 
 163 
 
 74-1 
 
 3 21 
 
 5.20 
 
 5 
 
 5 
 
 .418 
 
 .0056 
 
 Adipose tissue 
 
 23 
 
 M 
 
 45 
 
 14' 
 
 63.5 
 
 3 25 
 
 
 9 
 
 9 
 
 .361 
 
 -0057 
 
 
 24 
 
 M 
 
 29 
 
 154 
 
 70 
 
 3 28 
 
 5.30 
 
 5 ' 3 
 
 .431 
 
 (.0062) 
 
 Catarrhal in'fn 
 
 Average .0063 
 
 In this average all bracketed numbers are omitted. 
 
 The results are also shown in a curve (Fig. 5), with body weight 
 in kilograms as abscissae, and grams of carbon dioxide excreted per 
 minute as ordinate. The curve was drawn as follows: The points rep- 
 resenting the excretion of the various subjects were first plotted in 
 the usual manner. The average excretion of carbon dioxide per minute 
 per kilogram of body weight (.0063 grams) having been found, the to- 
 tal excretion per minute was calculated for a hypothetical person hav- 
 ing a body weight of 50 kilograms. This formed one point on the 
 curve of average excretion. The value for subject 14 which coincided 
 with the average, formed a second point. These points were now con- 
 nected by a straight line giving, of course, the curve of average excre- 
 tion for a subject of any weight. 
 
 This average, it will be observed, is approximately the mean of 
 the lowest result obtained by Johanssen .0048 grams (see table III) 
 and the highest result by Tigerstedt and Sonden .00792 grams. It is 
 about 5% higher than the average of the results of Johanssen and Mag- 
 nus-Levy (experiments 4, 5, and 3, table III). This result was ob- 
 tained on a class of persons who were for the greater part exceptionally 
 vigorous. Furthermore, with few exceptions, the subjects were acting 
 for the first time as subject in a respiration experiment. Had the ex- 
 periment been repeated several tims with each subject, the average re- 
 sults would perhaps have been somwhat lower than that given in table 
 III. 
 
 3. Results: It will be noted that the rates of excretion of carbon di- 
 
 22 
 
oxide of subject number 8, a woman having a body weight of 40 kilograms, 
 and of number 15, a man weighing 86.4 kilograms, was nearly the saino, 
 the value for each closely approximating the average; also that the sub- 
 jects whose values vary widely from the average, belonged, for the 
 greater part, to one of these two classes, a. Those whose values are 
 represented on the chart by Ad. The low results in these cases (2, 10, 
 22) was probably due to the large amount of adipose tissue present in 
 the body, since the metabolism in this form of tissue is very weak. b. 
 Those whose values are represented by N on the chart. Those indicated 
 in this manner were troubled with indigestion, number 13 having had 
 severe nausea, and number 20 slight nausea at the time of the experi- 
 ment. 
 
 4. Conclusions. 
 
 1. In a series of experiments such as that described in this sec- 
 tion, the results are modified somewhat, in individual cases, by the state 
 of health of the subject. Colds and indigestion apparently increase the 
 rate of excretion of carbon dioxide per unit of body weight. 
 
 2. The amount of carbon dioxide excreted per kilogram of body 
 weight is apparently greatly lowered by adipose tissue present in large 
 amounts in the body of the subject. 
 
 V. INFLUENCES WHICH MODIFY THE RATE OF EXCRETION 
 OF CARBON DIOXIDE DURING REST.* 
 
 Introduction. This work was suggested by that of Lombard^ 
 on "Some of the influences which affect the power of muscular contrac- 
 tion." In that research, which was made with the ergograph, Lombard 
 found that, in general, there was a fall of muscular power during the 
 day, this result being noted on eighteen out of a series of twenty-three 
 days. However, on certain days, the fall in power due to fatigue was 
 slight and on five days the power was greater at the last experiment 
 than at the first. These exceptions led to the suspicion that barometric 
 changes had an influence on muscular endurance. When later a com- 
 parison was made between Lombard's endurance curve arid the curve 
 of barometric height, it was found that, while no constant relationship 
 existed between the two variables, they varied in the same sense on 
 twenty out of twenty-three days; i. e., in general "when the barometer 
 rose during the day, or fell less than on the preceding day, the muscu- 
 lar endurance either rose, or fell Jess than on the preceding day." 
 
 It has been shown furthermore, that while a diminution of baro- 
 metric pressure increases both the respiration rate and the volume of 
 air respired, after allowance is made for the increase of volume due to 
 the lower pressure the volume respired is less (Speck). 
 
 Now, the effect of increasing barometric pressure upon the power 
 of the muscular system might possibly be due to some influence 
 
 * This paper was accepted for publication bv the officers of Section VIII, d. Eighth 
 International Congress of Applied Chemistry, and was read before the Section at a stat- 
 ed meeting on September 11, 1912; BIOCHEMICAL BULLETIN, 1912, ii, p. 153. 
 
 23 
 
exerted through the nervous and circulatory systems tending to in- 
 crease the readiness of metabolism; if such were the case then a varia- 
 tion in barometric height should b^ accompanied by a variation, in the 
 same sense, in the rate of excretion ot! carbon dioxide. 
 
 Plan of the experiments. It seemed. that a series of experiments 
 carried out for a month on three healthy subjects might throw light 
 on this question, and also give interesting results as regards the effect 
 of other conditions on the rate of caibon dioxide excretion. A series 
 of respiration experiments was planned, accordingly, for three subjects, 
 A. and B, students in the University of Michigan, and the writer, <?. 
 A and B were 24 and 22 years of age respectively, and weighed, with- 
 out clothing, 158 and 159 % pounds. was 46 years of age and weigh- 
 ed, exclusive of clothing, 148 pounds. Each subject was to live his reg- 
 ular daily life except that no vigorous muscular exercise was to be en- 
 gaged in immediately preceding any experiment, and that nothing 
 whatever was to be eaten between meals. The plan of work is indi- 
 cated in the appended summary, \vhere the data for the third part of 
 each experiment are placed below those for the first and second: 
 
 
 Hour 
 
 Re- 
 
 First 
 
 I Time until 
 
 
 Second 
 
 
 Subject 
 
 of 
 
 dined 
 
 experi 
 
 Breakfast next 
 
 Reclined 
 
 experi 
 
 Dinner 
 
 
 Ris 
 
 
 merit 
 
 experiment 
 
 
 meat 
 
 
 
 ing 
 
 
 
 \ 
 
 
 begun 
 
 
 A | 6 
 
 6:45 
 
 7:00 |7:40-8:00| 4 hr. 
 
 11:45 
 
 12:00 
 
 12:40 
 
 B 6 
 
 7:05 
 
 7:20 8:00-8:20 4 hr. 
 
 12:05 
 
 12:20 
 
 1:00 
 
 C 
 
 6 
 
 7:25 
 
 7:40 |8:00-8-20| 4% hr. 
 
 12:25 
 
 12:40 
 
 1:00 
 
 Subject 
 
 Time until next | 
 experiment Reclined 
 
 Third 
 i experiment 
 begun 
 
 launch 
 
 Experi- 
 menter 
 
 A 
 B 
 C 
 
 4 hrs. 
 4 hrs. 
 4V 3 hrs. 
 
 4:45 
 5:00 
 5:25 
 
 5:00 
 
 I 6:2 
 
 5:40 
 
 5:40 
 6:00 
 6:00 
 
 C 
 
 A 
 B 
 
 The routine of work was as follows: The subjects rose at 6 o'clock 
 reaching the laboratory at about 6:35. A reclined upon a couch at 6:45 
 in prepartion for the first experiment. B and C prepared all the appa- 
 ratus, making the initial calibration of the balance, weighing the guard 
 tubes, reading and recording the barometric height, the outdoor and 
 room temperature, etc. In order to enable the experimenter to judge 
 the better as to the physical condition of each subject, mouth tempera- 
 ture and pulse were also taken and lecorded. This routine at the lab- 
 oratory was followed at 12 M. and 5 P. M. 
 
 24 
 
TABLE IV. 
 
 Data showing the excretion of carbon dioxide by subjects A B. and 
 (7, in milligrams p^r minute. 
 
 Date 
 
 Subject A 
 
 Subject B 
 
 Subject C 
 
 December 7 A. M 
 
 12 M 
 
 5 P. M 
 
 7A.M. 12 M. 
 
 5P.M 
 
 1 A.M. 12 M 
 
 5 P. M. 
 
 23 
 24 
 
 406 
 
 438 
 
 422 
 460 
 
 447 
 
 381 
 
 489 
 
 498 
 422 
 
 ~56T 
 541 
 
 406 
 419 
 
 390 
 409 
 
 I 447 
 409 
 
 26 
 
 442 
 
 448 
 
 466 
 
 514 
 
 429 
 
 (743) 
 
 422 
 
 403 
 
 428 
 
 27 
 
 422 
 
 453 
 
 466 
 
 535 
 
 434 
 
 548 
 
 390 
 
 403 
 
 390 
 
 28 
 
 403 
 
 448 
 
 (635) 
 
 488 
 
 507 
 
 498 
 
 397 
 
 375 
 
 419 
 
 29 
 
 407 
 
 422 
 
 381 
 
 520 
 
 553 
 
 546 
 
 382 
 
 387 
 
 456 
 
 30 
 
 438 
 
 483 
 
 405 
 
 529 
 
 495 
 
 518 
 
 419 
 
 381 
 
 374 
 
 31 
 
 425 
 
 470 
 
 444 
 
 (647) 
 
 489 
 
 476 
 
 390 
 
 362 
 
 438 
 
 Jan. 
 
 
 
 
 - j 
 
 
 
 
 
 2 
 
 433 
 
 487 
 
 480 
 
 438 
 
 (611) 
 
 570 
 
 393 
 
 422 
 
 473 
 
 3 
 
 470 
 
 436 
 
 422 
 
 416 
 
 462 
 
 508 
 
 394 
 
 377 
 
 422 
 
 4 
 
 507 
 
 435 
 
 480 
 
 537 
 
 442 
 
 553 
 
 
 
 386 
 
 448 
 
 5 
 
 469 
 
 473 
 
 442 
 
 528 
 
 466 
 
 515 
 
 410 
 
 
 
 396 
 
 6 
 
 458 
 
 466 
 
 442 
 
 - 
 
 525 
 
 531 
 
 449 
 
 403 
 
 476 
 
 7 
 
 465 
 
 442 
 
 432 
 
 439 
 
 560 
 
 466 
 
 406 
 
 386 
 
 411 
 
 9 
 
 416 
 
 436 
 
 436 
 
 410 
 
 442 
 
 462 
 
 390 
 
 380 
 
 448 
 
 10 
 
 416 
 
 459 
 
 448 
 
 455 
 
 506 
 
 
 
 383 
 
 425 
 
 473 
 
 11 
 
 456 
 
 439 
 
 426 
 
 453 
 
 422 
 
 526 
 
 363 
 
 402 
 
 337 
 
 12 
 
 446 
 
 
 
 
 
 543 
 
 
 
 
 
 388 
 
 
 
 
 
 13 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 14 
 
 405 
 
 462 
 
 445 
 
 
 
 476 
 
 504 
 
 398 
 
 427 
 
 
 
 16 
 
 436 
 
 496 
 
 449 
 
 469 
 
 531 
 
 440 
 
 402 
 
 396 
 
 437 
 
 17 
 
 412 
 
 453 
 
 
 
 418 
 
 460 
 
 
 
 
 
 459 
 
 
 
 18 
 
 377 
 
 407 
 
 462 
 
 
 
 459 
 
 469. 
 
 364 
 
 442 
 
 435 
 
 19 
 
 472 
 
 487 
 
 422 
 
 445 
 
 474 
 
 409 
 
 403 
 
 438 
 
 429 
 
 20 
 
 469 
 
 476 
 
 436 
 
 402 | 455 
 
 432 
 
 402 
 
 474 
 
 419 
 
 21 
 
 462 436 
 
 493 
 
 399 
 
 442 | 493 
 
 406 
 
 448 
 
 434 
 
 
 I 
 
 
 
 | 
 
 
 
 
 23 
 
 428 
 
 481 
 
 429 
 
 509 
 
 442 
 
 436 
 
 396 
 
 449 
 
 429 
 
 24 
 
 422 
 
 517 
 
 495 
 
 500 
 
 459 
 
 537 
 
 409 
 
 460 
 
 429 
 
 25 
 
 422 
 
 475 
 
 402 
 
 
 
 528 
 
 486 
 
 422 
 
 468 
 
 428 
 
 26 
 
 495 | 
 
 561 
 
 
 
 
 
 
 
 
 
 422 
 
 422 
 
 
 
 Averages 
 
 438 
 
 462 
 
 443 
 
 472 
 
 476 
 
 501 
 
 401 
 
 414 
 
 427 
 
 
 25 
 
Results. The result of this series of experiments are shown in Ta- 
 ble IV in miligrams of carbon dioxide excretion per minute. It will be 
 noted that A's average for the mid-day experiments is considerably 
 higher than that for the morning and evening experiments. This is 
 due in part, at last, to the fact that this subject took his heartiest meal 
 in the morning. The excretion of carbon dioxide for B and C, on the 
 other hand, was greatest in the evening, since these subjects took 
 their dinner at 1 p. m. 
 
 The remarkably high excretion shown for A at the evening experi- 
 ment of December 28 (635 mg., while the average for that hour for Uiis 
 subject is only 443 mg.) is explained as follows: This subject went 
 skating in the afternoon of that day and at about 2:30 o'clock had the 
 misfortune to break through the ice, becoming wet to the neck. On be- 
 ing rescued, he walked about two miles in his frozen clothing, exposed 
 meanwhile to a strong wind at a temperature of about 6. C. On reach- 
 ing his room he took a thorough rubdown, made a change of clothing, 
 rested for one and one-half hours, and appeared at the laboratory at 
 the usual hour for the experiments, with the result stated above. It 
 will be noted that all of this subject's values for the following day, es- 
 pecially that of the evening, were much below the average, indicating 
 a reaction from the exposure and excitement of the preceding day. The 
 high excretion of the morning of January 4 is supposed to be due to 
 lunch eaten late on the preceding evening; that of 12 o'clock, January 
 26, to an exceptionally heavy morning meal; and the low result of the 
 evening of January 19 to an especially light midday meal. 
 
 The irregularity of results obtained from B are somewhat difficult 
 to explain. Those of the morning of December 27, 30 and 31, were due 
 to lunch eaten late the preceding evening and in the case of the two 
 latter results, also in part to excessive haste to reach the laboratory in 
 time for the regular experiment. Other high results, especially those 
 of 5 p. m., December 26, and of 12 m., January 2, were undoubtedly 
 due to indigestion. 
 
 Passing now to a study of the relation of carbon dioxide excretion 
 to barometric changes, Figure 6 will be found to embody, in the form 
 of curves, the results already given in Table IV, with time as abscissae, 
 and miligrams of carbon dioxide per minute as ordinates; it presents 
 curves for A, B and C, together with that for the barometer in milli- 
 meters of mercury and of the outdoor temperature in degrees centi- 
 grade. The temperature of the room was practically constant through- 
 out the series of experiments. Three curves are given for each subject 
 where the necessary data were at hand. In each case the morning, 
 midday and evening curves are represented, respectively, by solid, long- 
 dash and short-dash lines. 
 
 Analysis of the Results. Comparison of the data for barometric 
 pressure and carbon dioxide excretion. Before proceeding to a rigor- 
 ous mathematical investigation of the relationship between barometric 
 change and carbon dioxide excretion, it seemed desirable to make a 
 
 26 
 
comparison of these two variables at a number of the dates on which 
 especially marked barometrical fluctuations took place, since in such 
 cases the effect would be more pronounced and less likely to be masked 
 by other varying conditions, such as amount and character of the pre- 
 ceding meal, character of muscular exercise, etc. To facilitate such a 
 comparison, Tables V., VI., and VII, were prepared; they indicate ex- 
 periment number; dates between which the comparison is made; baro- 
 metric height, rise or fall; subject, carbon dioxide for the two days be- 
 tween which comparison is made; rise or fall of excretion; and rela- 
 tion between barometric change and carbon dioxide excretion, whether 
 direct or inverse. Taking first the morning values, it was found that 
 the barometer rose between 7 a. m., December 23, and 7 a. m., Decem- 
 ber 24, from 739 to 746, or 7mm. During the same period the excre- 
 tion of carbon dioxide of the three subjects changed as follows: That of 
 A from 406 to 438 mg. per minute, an increase of 32 mg.; that of B 
 from 381 to 489, an increase of 108 mg. and that of C from 406 to 419, 
 an increase of 13 mg. per minute. Thus with rising barometer there 
 was an increase in the rate of excretion of carbon dioxide in the case 
 of each subject. A similar result is obtained in four other morning 
 experiments (two subjects). In three morning experiments there are 
 two direct results each. One experiment shows two indirect results, i. 
 e., there is a change in carbon dioxide excretion which is opposite in 
 sign to that in the barometer. 
 
 Summing up the results of the morning experiments we have the 
 following: Eleven experiments were carried out on A, seven on B, and 
 eleven on C. The degree of correspondence of barometric change with 
 carbon dioxide excretion was: 
 
 A, 7 cases out of 11, or 63.6 per cent. 
 
 B, 6 cases out of 7, or 85.7 per cent. 
 
 C, cases out of 11, or 55.5 per cent. 
 
 -27 
 
x 
 
 Izi 
 
 O 3 
 
 , 
 -8 
 
 -l 
 
 o u x \ 
 
 &* 1 1 
 
 z z < 
 
 a o o 
 
 *sr? 
 
 !| 
 
 CVJ ^ 
 
 g* 
 
 oj| 
 
 &2 
 bti 
 
 55 
 
 uf 
 
 T3 O 
 
 oSf 
 
 PQ : 
 
 < 8 
 
 (A U 
 
 ^ SI 
 
 IS 1 
 
 3^ 
 
 M * 
 
 H 
 
 J* 
 
 fO v 
 
 s 
 
 S|i 
 
 II 
 
 &!| 
 
 3 
 U 
 
 1 
 
 O 
 
TABLE V Data obtained at 7 a. m. 
 
 No 
 
 Date 
 Dec. 
 
 Barometer 
 
 "o 
 
 V 
 
 15" 
 
 Excretion of carbon 
 dioxide 
 
 Relation be- 
 tween barome- 
 tric change 
 & carbon diox- 
 ide excretion 
 
 Heights, mm 
 
 Rise, 
 mm 
 
 Fall, 
 mm 
 
 Per 
 
 minute 
 mg. 
 
 Rise, 
 mg. 
 
 Fall, 
 mg. 
 
 Direct 
 
 Inverse 
 
 1 
 
 23-24 
 
 739 -746 
 
 7. 
 
 ~ 
 
 A 
 B 
 
 406-438 
 381-489 
 
 32 
 
 108 
 
 
 
 32 
 
 108 
 
 
 
 
 
 
 
 G 
 
 406-419 
 
 13 
 
 
 
 13 
 
 
 2 
 
 26-28 
 
 745.1-721 
 
 
 
 24.1 
 
 A 
 
 442-403 
 
 
 
 39 
 
 39 
 
 
 
 
 
 
 
 B 
 
 514-488 
 
 
 
 26 
 
 26 
 
 
 
 
 
 
 
 G 
 
 422-397 
 
 
 
 25 
 
 25 
 
 
 3 
 
 28-29 
 
 721 -742.1 
 
 21.1 
 
 
 
 A 
 
 403-407 
 
 4 
 
 
 
 4 
 
 
 
 
 
 
 
 B 
 
 488-520 
 
 32 
 
 
 
 32 
 
 
 
 
 
 
 
 G 
 
 397-382 
 
 
 
 15 
 
 
 
 15 
 
 4 
 
 29-31 
 
 742.5-736 
 
 
 
 6.1 
 
 A 
 
 407-425 
 
 18 
 
 
 
 
 
 18 
 
 
 
 
 
 
 B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 G 
 
 382-390 
 
 8 
 
 
 
 
 
 8 
 
 5 
 
 Jan. 
 
 
 
 
 
 
 
 
 
 
 
 2-4 
 
 737.1-743.5 
 
 6.4 
 
 
 
 A 
 
 433-507 
 
 74 
 
 
 
 74 
 
 
 
 
 
 
 
 B 
 
 438-537 
 
 99 
 
 
 
 99 
 
 
 
 
 
 
 
 G 
 
 393-394 
 
 1 
 
 
 
 1 
 
 
 6 
 
 5-7 
 
 743.5-732.5 
 
 
 
 11. 
 
 A 
 
 469-465 
 
 
 
 4 
 
 4 
 
 
 
 
 
 
 
 B 
 
 528-439 
 
 
 
 89 
 
 89 
 
 
 
 
 
 
 
 C 
 
 410-406 
 
 
 
 4 
 
 4 
 
 
 7 
 
 11-12 
 
 753.9-737.1 
 
 
 
 16.8 
 
 A 
 
 456-446 
 
 
 
 10 
 
 10 
 
 
 
 
 
 
 
 B 
 
 453-543 
 
 90 
 
 
 
 
 
 90 
 
 
 
 
 
 
 G 
 
 363-388 
 
 25 
 
 
 
 
 
 25 
 
 8 
 
 12-14 
 
 737.1-751.2 
 
 14.1 
 
 
 
 A 
 
 446-405 
 
 
 
 41 
 
 
 
 41 
 
 
 
 
 
 
 B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 G 
 
 388-398 
 
 10 
 
 
 
 10 
 
 
 9 
 
 18-19 
 
 748.1-739.3 
 
 
 
 8.9 
 
 A 
 
 377-472 
 
 95 
 
 
 
 
 
 95 
 
 
 
 
 
 
 B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 G 
 
 364-403 
 
 39 
 
 
 
 
 
 39 
 
 10 
 
 23-24 
 
 749 -739.8 
 
 
 
 9.2 
 
 A 
 
 428-422 
 
 
 
 6 
 
 6 i 
 
 
 
 
 
 
 
 B 
 
 509-500 
 
 
 
 9 
 
 9' 
 
 
 
 
 
 
 
 G 
 
 396-409 
 
 13 
 
 
 
 
 
 13 
 
 11 
 
 24-26 
 
 739.8-758.8 
 
 19. 
 
 
 
 A 
 
 422-495 
 
 73 
 
 
 
 73 
 
 
 
 
 
 
 
 B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 G 
 
 409-422 
 
 13 
 
 
 
 13 
 
 
The direct result from the midday experiments were as follows: 
 
 A, 3 cases out of 7,, or 42.8 per cent. 
 
 B, 3 cases out of 9, or 33.3 per cent. 
 C, 6 cases out of 9, or 66.6 per cent. 
 
 From the evening experiments the direct results were: 
 
 A, 3 cases our of 6, or 50 per cent. 
 
 B, 4 cases out of 9, or 44.4 per cent. 
 C, 4 cases out of 8, or 50 per cent. 
 
 TABLE VI. 
 
 Data obtained at 12 m. 
 
 Dec. 
 
 
 
 
 
 
 
 
 No. Date 
 1 23-24 
 
 Barometer 
 739.1r746.2 
 
 Rise Fall Subject 
 7.1 A 
 
 Carbon 
 Dioxide 
 422^460 
 
 Rise 
 38 
 
 Fall 
 
 Direct In 
 verse 
 38 
 
 
 
 B 
 
 498-422 
 
 
 76 
 
 
 76 
 
 
 
 C 
 
 390-409 
 
 19 
 
 
 19 
 
 
 2 26-28 
 
 742.5-726.9 
 
 15.6 A 
 
 446-448 
 
 
 
 
 
 
 
 B 
 
 429-507 
 
 78 
 
 
 
 78 
 
 
 
 C 
 
 403-375 
 
 
 28 
 
 28 
 
 
 3 28-29 
 
 726.9-742-5 
 
 11.6 A 
 
 448-422 
 
 
 26 
 
 
 26 
 
 
 
 B 
 
 507-553 
 
 46 
 
 
 46 
 
 
 Jan 
 
 
 C 
 
 375-387 
 
 12 
 
 
 12 
 
 
 4 29-31 
 
 742.5-736.1 
 
 6.4 A 
 
 422-470 
 
 48 
 
 
 
 48 
 
 
 
 B 
 
 553-489 
 
 
 64 
 
 64 
 
 
 
 
 C 
 
 387-362 
 
 
 25 
 
 25 
 
 
 5 2-4 
 
 738.9-745.1' 
 
 6.2 A 
 
 487r435 
 
 
 52 
 
 
 62 
 
 
 
 B 
 
 (611-442) 
 
 
 169 
 
 
 169 
 
 
 
 C 
 
 422-386 
 
 
 36 
 
 
 36 
 
 6 5-7 
 
 743.5-732.9 
 
 10.6 A 
 
 473-442 
 
 
 31 
 
 31 
 
 
 
 
 B 
 
 466-560 
 
 94 
 
 
 
 94 
 
 
 
 C 
 
 403-386 
 
 
 17 
 
 
 17 
 
 7 18-19 
 
 747.7-740.1 
 
 7.8 A 
 
 407-487 
 
 80 
 
 
 
 80 
 
 
 
 B 
 
 459-474 
 
 15 
 
 
 
 16 
 
 
 
 C 
 
 442-438 
 
 
 4 
 
 4 
 
 
 8 23-24 
 
 749.8-738.8 
 
 11. A 
 B 
 
 480-517 
 442-459 
 
 37 
 17 
 
 
 
 37 
 17 
 
 
 
 C 
 
 449-460 
 
 11 
 
 
 
 11 
 
 9 24-26 
 
 738.8-758.5 
 
 19.6 A 
 
 517 r 561 
 
 44 
 
 
 44 
 
 
 
 
 B 
 
 459-528 
 
 69 
 
 
 69 
 
 
 
 
 C 
 
 460-422 
 
 
 38 
 
 
 38 
 
 30 
 
TABLE VII. 
 
 Data obtained at 5 p. m. 
 
 No. Date Barometer Rise Fall Subject 
 
 Dec. 
 
 1 23-24 739.1-747.1 8 A 
 
 B 
 C 
 
 2 26-27 741.5-718.2 12.9 A 
 
 B 
 
 
 3 27-28 718.2-738.1 19.9 A 
 
 B 
 C 
 
 4 29-31 742.5-737.5 5 A 
 
 B 
 Jan. C 
 
 5 2-4 740-745 5 A 
 
 B 
 C 
 
 6 5-7 744.1-732.9 11.2 A 
 
 3 
 (3 
 
 7 18-19 742.9-739.5 3.4 A 
 
 B 
 C 
 
 8 23-24 747.8-740 7-8 A 
 
 B 
 
 /~< 
 
 9 24-25 740.755.1 15.1 A 
 
 B 
 C 
 
 Carbon Rise 
 Dioxide 
 
 Fall Direct In- 
 verse 
 
 567-541 
 
 26 
 
 
 26 
 
 447-409 
 
 38 
 
 
 38 
 
 466-466 
 
 
 
 
 (743-548) 
 
 195 
 
 195 
 
 
 428-390 
 
 38 
 
 38 
 
 
 466 635 
 
 169 
 
 169 
 
 
 548-498 
 
 50 
 
 
 50 
 
 390-419 
 
 39 
 
 39 
 
 
 381-444 
 
 63 
 
 63 
 
 
 546-476 
 
 70 
 
 70 
 
 
 456-438 
 
 18 
 
 18 
 
 
 480-480 
 
 
 
 
 570-553 
 
 17 
 
 
 17 
 
 473-448 
 
 25 
 
 
 25 
 
 442-432 
 
 10 
 
 10 
 
 
 515-466 
 
 49 
 
 49 
 
 
 396-411 
 
 
 
 15 
 
 462-422 
 
 40 
 
 40 
 
 
 469-409 
 
 60 
 
 60 
 
 
 435-429 
 
 6 
 
 6 
 
 
 429-495 
 
 66 
 
 
 66 
 
 436-537 
 
 101 
 
 
 101 
 
 429-429 
 
 
 
 
 495-402 
 
 93 
 
 
 93 
 
 537-486 
 
 51 
 
 
 51 
 
 429-428 
 
 1 
 
 
 1 
 
 Or, out of a total of seventy-seven experiments, there was direct rela- 
 tionship between barometric change and and carbon dioxide excretion 
 in forty-two experiments, or 54.5 per cent. 
 
 It will be seen from these results that the apparent degree of corre- 
 spondence, so far as it is revealed by this method of analysis, is greater 
 in the morning experiments than in those carried out at midday or in 
 the evening. This is probably due to the fact that in the morning not 
 merely the digestive organs, but the whole system, is in a more uniform 
 condition than at any other time during the twenty-four hours. 
 
 Application of the method of least squares. It now seemed desira- 
 ble to subject the results obtained in this series of experiments t3 a 
 more rigorous analysis than that just described, with a view of discov- 
 ering what is the degree of correlation between the two variables, the 
 
 31 
 
barometric height and the rate of excretion of carbon dioxide, during 
 muscular rest. The data obtained in the experiments were, therefore, 
 examined by the method of least squares, which was applied separately 
 to the three sets of data from each subject in order that the effect of 
 different times of day might be determined separately. 
 
 In Table VIII are given the barometric height and the correspond- 
 ing carbon dioxide excretionf; the problem is to find the correlation be- 
 tween these two quantities, and also the regression of carbon dioxide on 
 barometric height,i. e., the amount of change in excretion of carbon di- 
 oxide for a milimeter change in barometric height. The means of col- 
 umns 1 and 2 are obtained in the usual manner, by dividing the total 
 in each column by the number of experiments (N). Having obtained 
 these means, two additional columns are formed, giving the deviation 
 of each observation from the mean of its column. In columns 5 and 6 
 are entered the squares of the deviations (X 2 andY 2 ). The standard 
 deviation OJ is now obtained by dividing the sum of the squares in 
 the fifth column by the number of experiments, 2V, and extracting the 
 square root of the quotient; the standard deviation for y is, of coursa 
 found in the same manner. 
 
 / 1769.71 /ZY 3 II 
 
 -V-:-= 7 - 8and *>V V- 
 
 24951 
 
 -=29.3 
 29 ' IV 29 
 
 * The data are those obtained from morning experiments on subject A. 
 
 32 
 
Relation of Carbon Dioxide Excretion to 
 TABLE VIII 7 A. 
 
 Barometric Change. 
 M. 
 
 
 
 
 
 
 
 Products (x y) 
 
 Barometer 
 Millimetres 
 
 Carbon 
 Dioxide 
 
 X 
 
 y 
 
 o 
 X 
 
 O 
 
 y 
 
 Negative 
 
 Positive 
 
 739 
 
 Milligrams 
 406 
 
 4 
 
 32 
 
 16 
 
 1024 
 
 
 128 
 
 746 
 
 438 
 
 3 
 
 
 
 9 
 
 
 
 
 
 745.1 
 
 442 
 
 2.1 
 
 4 
 
 4.41 
 
 16 
 
 
 8.4 
 
 726.2 
 
 422 
 
 16.8 
 
 16 
 
 282.24 
 
 256 
 
 
 268.8 
 
 721 
 
 403 
 
 22 
 
 35 
 
 484 
 
 1225 
 
 
 770 
 
 742.1 
 
 407 
 
 -0.9 
 
 31 
 
 .81 
 
 961 
 
 
 27.9 
 
 740 
 
 438 
 
 3 
 
 
 
 9 
 
 
 
 
 736 
 
 425 
 
 7 
 
 13 
 
 49 
 
 169 
 
 
 91 
 
 737.1 
 
 433 
 
 5.9 
 
 5 
 
 34.81 
 
 25 
 
 
 29.5 
 
 741.3 
 
 470 
 
 1.7 
 
 32 
 
 2.89 
 
 1024 
 
 54.4 
 
 
 743.5 
 
 507 
 
 .5 
 
 69 
 
 .25 
 
 4761 
 
 
 34.5 
 
 743.5 
 
 469 
 
 .5 
 
 31 
 
 .25 
 
 961 
 
 
 15.5 
 
 742.3 
 
 458 
 
 .7 
 
 20 
 
 .49 
 
 400 
 
 14 
 
 
 732.5 
 
 465 
 
 10.5 
 
 27 
 
 110.25 
 
 729 
 
 283.5 
 
 
 751.5 
 
 416 
 
 8.5 
 
 22 
 
 72.25 
 
 484 
 
 187 
 
 
 751 . 4 
 
 416 
 
 8.4 
 
 22 
 
 70.86 
 
 484 
 
 184.8 
 
 
 753.9 
 
 456 
 
 10.9 
 
 18 
 
 118.81 
 
 324 
 
 
 196.2 
 
 736.1 
 
 446 
 
 5.9 
 
 8 
 
 34.81 
 
 64 
 
 47.2 
 
 
 751.2 
 
 405 
 
 8.2 
 
 33 
 
 67.24 
 
 1089 
 
 270.6 
 
 
 746.5 
 
 436 
 
 3.5 
 
 2 
 
 12.25 
 
 4 
 
 7 
 
 
 747.8 
 
 412 
 
 4.8 
 
 26 
 
 23.04 
 
 676 
 
 124.8 
 
 
 748.2 
 
 377 
 
 5.2 
 
 61 
 
 27.04 
 
 3721 
 
 317.2 
 
 
 739.3 
 
 472 
 
 3.7 
 
 34 
 
 13.69 
 
 1156 
 
 125.8 
 
 
 745.5 
 
 469 
 
 2.5 
 
 31 
 
 6.26 
 
 961 
 
 
 77.6 
 
 743.7 
 
 462 
 
 .7 
 
 23 
 
 .49 
 
 576 
 
 
 16.8 
 
 749. 
 
 428 
 
 6. 
 
 10 
 
 36 
 
 100 
 
 60 
 
 
 739.8 
 
 422 
 
 3.2 
 
 16 
 
 10.24 
 
 256 
 
 
 51.2 
 
 747.9 
 
 422 
 
 4.9 
 
 16 
 
 24.01 
 
 256 
 
 78.4 
 
 
 758.8 
 
 495 
 
 15.8 
 
 57 
 
 249.64 
 
 32-49 
 
 
 900.6 
 
 
 
 
 
 1769.71 
 
 24951 
 
 1754.7 
 
 2622.7 
 
 
 
 
 
 
 
 
 1754.7 
 
 868 
 
 -7.8 
 
 Coefficient of correlation 
 
 /J4951 _ 
 r2=r \'29~~ 
 
 Zxy __ 868 
 Nfft <r 2 ~~ 29XT.8 X 2 9 .3 
 
 12(T 2 
 
 Regression .45 
 
 0"a 
 
 33 
 
The products XY are now collected, the negative in column 7 and 
 the positive in column 8, and the totals determined. We have, then, 
 1754.7=+868. 
 
 Prom this coefficient of correlation (r) is obtained: 
 
 868 
 
 =+.12 
 
 29X.7.8X29.3 
 
 The positive sign of this coefficient indicates, of course, that the rela- 
 tionship between barometric change and carbon dioxide excretion in 
 this case is direct or that the two variables change in the same sense. 
 Since a coefficient of correlation of 1 indicates perfect correlation, the 
 result obtained in the series of experiments represented in Table IV 
 indicates a slight degree of correlation. The probable error of a cor- 
 relation coefficient of this value for a series of 25 observations is at 
 least 0.13 so that the value of r is 0.120.13. 
 
Relation of carbon dioxide excretion to barometric change. 
 TABLE IX A. 12 m. 
 
 Barometer 
 
 Carbon 
 dioxide 
 
 
 
 
 
 Products (XY) 
 
 reading, mm 
 
 excretion, mg. 
 
 X 
 
 Y 
 
 X 2 
 
 Y 2 
 
 Negative 
 
 Positive 
 
 739.1 
 
 422 
 
 4.2 
 
 r-40 
 
 17.64| 1,600 
 
 - | 168 
 
 746.2 
 
 460 
 
 2.9 
 
 - 2 
 
 8.41 
 
 4 
 
 5.8 
 
 
 
 742.5 
 
 448 
 
 0.8 
 
 14 
 
 0.64 
 
 196 
 
 ^ 
 
 11.2 
 
 722.1 
 
 453 
 
 21.2 
 
 c 
 
 449.44 
 
 81 
 
 
 
 i'jU.8 
 
 726.9 
 
 448 
 
 16.4 
 
 14 
 
 268.96 
 
 196 
 
 
 229.6 
 
 
 742.5 
 
 422 
 
 0.8 
 
 40 
 
 0.64 
 
 1,600 
 
 
 
 32 
 
 740.1 
 
 483 
 
 3.2 
 
 21 
 
 10.24 
 
 441 
 
 67.2 
 
 
 
 736.1 
 
 470 
 
 7.2 
 
 8 
 
 51.84 
 
 64 
 
 57.6 
 
 
 
 738.9 
 
 487 
 
 - 4.4 
 
 25 
 
 19.36 
 
 625 
 
 110. 
 
 
 
 742.9 
 
 436 
 
 - 0.4 
 
 26 
 
 0.16 
 
 676 
 
 
 
 10.4 
 
 74 F 1 
 
 4qr 
 
 1 8 
 
 27 
 
 9 04 
 
 700 
 
 48 fi 
 
 
 1 ^O . JL 
 
 743.5 
 
 ^00 
 
 473 
 
 I O 
 
 0.2 
 
 & i 
 
 11 
 
 O &T. 
 
 0.04 
 
 I tv 
 
 121 
 
 TiO D 
 
 2.2 
 
 739.9 
 
 466 
 
 - 3.4 
 
 4 
 
 11.56 
 
 16 
 
 13.6 
 
 , 
 
 7QO Q 
 
 442 
 
 -in 4 
 
 20 
 
 108 Ifi 
 
 400 
 
 
 908 
 
 1 - >_ . .' 
 
 745.8 
 
 TTLJ 
 
 436 
 
 J.V TC 
 
 2.5 
 
 AfU 
 
 26 
 
 J.VO . .LO 
 
 6.25 
 
 TtU V 
 
 676 
 
 65 
 
 UO 
 
 753.2 
 
 459 
 
 9.9 
 
 o 
 
 98.01 
 
 9 
 
 29.7 
 
 
 
 749.3 
 
 439 
 
 6.6 
 
 23 
 
 36.00 
 
 529 
 
 151.8 
 
 
 
 753.6 
 
 462 
 
 10.3 
 
 
 
 106.09 
 
 
 
 
 
 
 
 747.5 
 
 496 
 
 4.2 
 
 34 
 
 17.64| 1,156 
 
 
 
 142.8 
 
 748.1 
 
 453 
 
 4.8 
 
 - 9 
 
 23.04 81 
 
 43.2 
 
 
 
 747.9 
 
 407 
 
 4.6 
 
 55 
 
 21.16 
 
 3,025 
 
 253.0 
 
 
 
 740.1 
 
 487 
 
 3.2 
 
 25 
 
 10.24 
 
 625 
 
 80. 
 
 
 
 741.1 
 
 476 
 
 0.8 
 
 14 
 
 0.64 
 
 196 
 
 
 
 11.2 
 
 743.9 
 
 436 
 
 0.6 
 
 26 
 
 0.36 
 
 676 
 
 15.6 
 
 
 
 749.8 
 
 481 
 
 6.5 
 
 19 
 
 42.25 
 
 3611 
 
 
 
 123.5 
 
 738.8 
 
 517 
 
 - 4.5 
 
 55 
 
 20.25 
 
 3,025 
 
 247.5 
 
 
 
 752.9 
 
 475 
 
 9.6 
 
 13 
 
 92.16 
 
 169 
 
 
 
 124.8 
 
 758.4 
 
 561 
 
 15.1 
 
 99 
 
 228. 01| 9,801 
 
 1 
 
 1,494.9 
 
 1 
 
 11,642.43127,0781 1,174.61 2,749.4 
 
 1,174.4 
 
 1,574.6 
 
 27,078 
 
 Coefficient of correlation: 
 
 1,574.6 
 
 2(>7/) 1,574.6 
 
 28X7.65X31.1 
 
 =+0,230 
 
 0.2365 2 
 Regression = - - - =0.95 
 
 35 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE X A, 5 P. M. 
 
 Barometer 
 Millimetres 
 
 Carbon 
 Dioxide 
 Milligrams 
 
 X 
 
 * 
 
 X 2 
 
 Y 2 
 
 Products (xy) 
 
 Negative 
 
 Positive 
 
 741.1 
 
 741.1 
 
 447 
 
 466 
 
 4.1 
 1.9 
 
 4 
 23 
 
 16 . 81 
 3.61 
 
 16 
 
 529 
 
 43.7 
 
 16.4 
 
 718.2 
 
 466 
 
 24.8 
 
 23 
 
 615.04 
 
 529 
 
 570.4 
 
 
 742.5 
 
 381 
 
 .5 
 
 62 
 
 .25 
 
 3844 
 
 
 31 
 
 739 
 
 405 
 
 4 
 
 38 
 
 16 
 
 1444 
 
 
 152 
 
 737.5 
 
 444 
 
 5.5 
 
 1 
 
 30.25 
 
 1 
 
 5.5 
 
 
 740 
 
 480 
 
 3 
 
 37 
 
 9 
 
 1369 
 
 111 
 
 
 744.1 
 
 422 
 
 1.1 
 
 21 
 
 1.21 
 
 441 
 
 23.1 
 
 
 745 
 
 480 
 
 2 
 
 37 
 
 4 
 
 1369 
 
 
 74 
 
 744.1 
 
 442 
 
 1.1 
 
 1 
 
 1.21 
 
 1 
 
 1.1 
 
 
 739.1 
 
 442 
 
 3.9 
 
 -j 
 
 15.21 
 
 1 
 
 
 3.9 
 
 732.9 
 
 432 
 
 10.1 
 
 11 
 
 102.01 
 
 121 
 
 
 111.1 
 
 746 
 
 436 
 
 3 
 
 7 
 
 9 
 
 49 
 
 21 
 
 
 756.2 
 
 448 
 
 13.2 
 
 5 
 
 174.24 
 
 25 
 
 
 66 
 
 744.1 
 
 426 
 
 1.1 
 
 17 
 
 1.21 
 
 289- 
 
 18.7 
 
 
 753.8 
 
 445 
 
 10.8 
 
 2 
 
 116.64 
 
 4 
 
 
 21.6 
 
 711.1 
 
 449 
 
 4.1 
 
 6 
 
 16.81 
 
 36 
 
 
 24.6 
 
 742.9 
 
 462 
 
 i 
 
 19 
 
 ..01 
 
 361 
 
 1.9 
 
 
 739.5 
 
 422 
 
 3.5 
 
 19 
 
 12.25 
 
 361 
 
 
 66.5 
 
 743.9 
 
 436 
 
 .9 
 
 7 
 
 .81 
 
 49 
 
 6.3 
 
 
 744.3 
 
 493 
 
 1.3 
 
 50 
 
 1.69 
 
 2500 
 
 
 65 
 
 747.8 
 
 429 
 
 4.8 
 
 14 
 
 23.04 
 
 196 
 
 67.2 
 
 
 740 
 
 495 
 
 3 
 
 52 
 
 9 
 
 2604 
 
 156 
 
 
 755.1 
 
 402 
 
 12.1 
 
 41 
 
 146.41 
 
 1681 
 
 496.1 
 
 
 1315.71 17620 1522. 
 632.1 
 
 889.9 
 
 '1315.71 
 *'= ^ 'sa =7.4 
 
 632.1 
 
 24 
 
 =27.1 
 
 = 889,9. 
 
 Coefficient of Correlation^ 
 
 889.9 
 
 1^3=24X7.4X27.1= .16 
 
 16Xcr 2 
 
 Regression = =' .58 
 
 <r a 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE XI B, 7 A. M. 
 
 Barometer 
 Millimetres 
 
 Carbon 
 Dioxide 
 Milligrams 
 
 X i 
 
 Y 
 
 X 
 
 Y 2 
 
 Products (xy ) 
 Negative Positive 
 
 739 
 
 381 
 
 2.6 
 
 97 
 
 6.76 
 
 9409 
 
 
 252.2 
 
 746 
 
 489 
 
 4.4 
 
 11 
 
 19.36 
 
 121 
 
 
 48.4 
 
 745.1 
 
 514 
 
 3.5 
 
 36 
 
 12.25 
 
 1296 
 
 
 126 
 
 726.2 
 
 535 
 
 15.4 
 
 57 
 
 237.16 
 
 3249 
 
 877.8 
 
 
 721 
 
 488 
 
 20.6 
 
 10 
 
 424.36 
 
 100 
 
 260 
 
 
 742.1 
 
 520 
 
 .5 
 
 42 
 
 .25 
 
 1764 
 
 
 21 
 
 740 
 
 529 
 
 1.6 
 
 51 
 
 2.56 
 
 2601 
 
 81.6 
 
 
 737.1 
 
 438 
 
 4.5 
 
 40 
 
 20.25 
 
 1600 
 
 
 180 
 
 741.3 
 
 416 
 
 - .3 
 
 62 
 
 .09 
 
 2844 
 
 
 18.6 
 
 743.5 
 
 537 
 
 1.9 
 
 59 
 
 3.61 
 
 3481 
 
 
 112.1 
 
 743.5 
 
 528 
 
 1.9 
 
 50 
 
 3.61 
 
 2500 
 
 
 95 
 
 732.5 
 
 439 
 
 9.1 
 
 39 
 
 82.81 
 
 1521 
 
 
 354.9 
 
 751.5 
 
 410 
 
 9.9 
 
 68 
 
 98.01 
 
 4624 
 
 673.2 
 
 
 751.4 
 
 455 
 
 9.8 
 
 oq 
 ^o 
 
 96.04 
 
 529 
 
 225.4 
 
 
 753.9 
 
 453 
 
 12.3 
 
 25 
 
 151.29 
 
 625 
 
 307.5 
 
 
 737.1 
 
 543 
 
 4.5 
 
 65 
 
 20.25 
 
 4225 
 
 292.5 
 
 
 746.5 
 
 469 
 
 4.9 
 
 n 
 
 24.01 
 
 81 
 
 44.1 
 
 
 747.8 
 
 418 
 
 6.2 
 
 60 
 
 38.44 
 
 3600 
 
 37.2 
 
 
 739.3 
 
 445 
 
 2.3 
 
 33 
 
 5.29 
 
 1089 
 
 
 75.9 
 
 745.5 
 
 402 
 
 3.9 
 
 76 
 
 15.21 
 
 5775 
 
 295.4 
 
 
 743.7 
 
 399 
 
 2.1 
 
 79 
 
 4.41 
 
 6241 
 
 165.9 
 
 
 749 
 
 509 
 
 7.4 
 
 31 
 
 54.76 
 
 961 
 
 
 229.4 
 
 739.8 
 
 500 
 
 1.8 
 
 22 
 
 3.24 
 
 484 
 
 39.6 
 
 
 1324.02 59721 3301.2 
 1513.5 
 
 1787.7 
 
 f 
 
 '- v 
 
 59721 
 
 24 
 
 =49.8 
 
 2 (xy)= 1787.7 
 
 Coefficient of Correlation 
 
 1787.7 
 
 24X7.4X49.8 
 
 =.2 
 
 .2(T 2 
 
 Regression^ - -= .13 
 
 1513.5 
 
 37 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE XII B, 12 M. 
 
 Carbon 
 Barometer Dioxide 
 Millimetres Milligrams x 
 
 739.1 498 ^3.6 
 
 y 
 
 "l7 
 
 X 
 
 12. 
 
 2 
 96 
 
 2 
 
 289 
 
 Products txy) 
 Negative Positive 
 
 61.2 
 
 746 
 
 .2 
 
 422 
 
 3 
 
 .5 
 
 59 
 
 12. 
 
 25 
 
 3481 
 
 206 
 
 .5 
 
 
 742 
 
 .5 
 
 429 
 
 
 .2 
 
 52 
 
 
 04 
 
 2704 
 
 10 
 
 .4 
 
 
 722 
 
 .1 
 
 434 
 
 20 
 
 .6 
 
 48 
 
 424. 
 
 36 
 
 2304 
 
 
 
 988.8 
 
 726 
 
 .9 
 
 507 
 
 15 
 
 .8 
 
 26 
 
 249. 
 
 64 
 
 676 
 
 410 
 
 .8 
 
 
 742 
 
 .5 
 
 553 
 
 
 
 .2 
 
 72 
 
 . 
 
 04 
 
 5184 
 
 14 
 
 .4 
 
 
 740 
 
 .1 
 
 495 
 
 2 
 
 .6 
 
 14 
 
 6. 
 
 76 
 
 196 
 
 36 
 
 .4 
 
 
 736 
 
 .1 
 
 489 
 
 6 
 
 .6 
 
 8 
 
 43. 
 
 56 
 
 64 
 
 52 
 
 .8 
 
 
 742 
 
 .9 
 
 462 
 
 
 .2 
 
 19 
 
 
 04 
 
 361 
 
 3 
 
 .8 
 
 
 745 
 
 .1 
 
 442 
 
 2 
 
 .4 
 
 39 
 
 5. 
 
 76 
 
 1521 
 
 93 
 
 .6 
 
 
 743 
 
 .5 
 
 466 
 
 
 .8 
 
 15 
 
 
 64 
 
 225 
 
 12 
 
 
 
 739 
 
 .9 
 
 525 
 
 2 
 
 .8 
 
 44 
 
 7. 
 
 84 
 
 1936 
 
 123 
 
 .2 
 
 
 732 
 
 .9 
 
 560 
 
 2 
 
 .8 
 
 79 
 
 7. 
 
 84 
 
 6241 
 
 221 
 
 .2 
 
 
 745 
 
 .8 
 
 442 
 
 3 
 
 .1 
 
 39 
 
 9. 
 
 61 
 
 1521 
 
 120 
 
 .9 
 
 
 753.2 
 
 506 
 
 10 
 
 .5 
 
 25 
 
 110. 
 
 25 
 
 625 
 
 
 
 262.5 
 
 749 
 
 .3 
 
 422 
 
 6 
 
 .6 
 
 59 
 
 43. 
 
 56 
 
 3481 
 
 389 
 
 .4 
 
 
 753 
 
 .6 
 
 476 
 
 10 
 
 .9 
 
 5 
 
 118. 
 
 81 
 
 25 
 
 54 
 
 .5 
 
 
 747 
 
 .5 
 
 531 
 
 4 
 
 .8 
 
 50 
 
 23. 
 
 04 
 
 2500 
 
 
 
 240 
 
 748 
 
 .1 
 
 460 
 
 5 
 
 .4 
 
 21 
 
 29. 
 
 16 
 
 441 
 
 113 
 
 .4 
 
 
 747 
 
 .9 
 
 459 
 
 5 
 
 .2 
 
 22 
 
 27. 
 
 04 
 
 484 
 
 114 
 
 .4 
 
 
 740 
 
 .1 
 
 474 
 
 2 
 
 .6 
 
 ^-1 
 
 6. 
 
 76 
 
 49 
 
 
 
 18.2 
 
 744 
 
 .1 
 
 455 
 
 1 
 
 .4 
 
 26 
 
 1. 
 
 96 
 
 676 
 
 36 
 
 .4 
 
 
 743 
 
 .9 
 
 442 
 
 1 
 
 .2 
 
 39 
 
 1. 
 
 44 
 
 1521 
 
 46 
 
 .8 
 
 
 749 
 
 .8 
 
 442 
 
 7 
 
 .1 
 
 39 
 
 50. 
 
 41 
 
 1521 
 
 276 
 
 .9 
 
 
 738 
 
 .8 
 
 459 
 
 3 
 
 .9 
 
 22 
 
 15. 
 
 21 
 
 484 
 
 
 
 85. 8 
 
 752 
 
 .9 
 
 528 
 
 10 
 
 .2 
 
 47 
 
 104. 
 
 4 
 
 2209 
 
 
 
 479.1 
 
 1313.02 40719 2399 2074.7 
 
 2074.7 
 
 324.3 
 
 26 
 
 = 324.3 
 
 Coefficient of Correlation^ ___ _ =: 
 
 26X7.1X39.5 
 
 .04cr 2 
 
 Regression^ = .09 
 
 0*1 
 
 38 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE XIII B, 5 P. M. 
 
 Barometer 
 Millimetres 
 
 731.1 
 
 Carbon 
 Dioxide 
 Milligrams x 
 
 567 2.9 
 
 y 
 66 
 
 8 
 
 x' 2 y 2 
 .41 4356 
 
 Products [xy] 
 Negative Positive 
 
 191.4 
 
 747.1 
 
 541 
 
 5.1 
 
 40 
 
 26 
 
 .01 1600 
 
 
 204 
 
 718.2 
 
 548 
 
 23.8 
 
 47 
 
 566 
 
 .44 2209 
 
 1118.6 
 
 
 738.1 
 
 498 
 
 3.9 
 
 o 
 
 15 
 
 .21 9 
 
 
 11.7 
 
 742.5 
 
 546 
 
 .5 
 
 45 
 
 
 .25 2025 
 
 
 22.5 
 
 739 
 
 518 
 
 3 
 
 17 
 
 9 
 
 289 
 
 51 
 
 
 737.5 
 
 476 
 
 4.5 
 
 25 
 
 20 
 
 .25 625 
 
 
 112.5 
 
 740 
 
 570 
 
 a 
 
 69 
 
 4 
 
 4761 
 
 138 
 
 
 744.1 
 
 508 
 
 2.1' 
 
 7 
 
 4 
 
 .41 49 
 
 
 14.7 
 
 745 
 
 553 
 
 3 
 
 52 
 
 9 
 
 2704 
 
 
 156 
 
 744.1 
 
 515 
 
 2.1 
 
 14 
 
 4 
 
 .41 196 
 
 
 29.4 
 
 739.1 
 
 531 
 
 2.9 
 
 30 
 
 8 
 
 .41 900 
 
 87 
 
 
 732.9 
 
 466 
 
 9.1 
 
 35 
 
 82 
 
 .81 1225 
 
 
 318.5 
 
 746 
 
 462 
 
 4 
 
 39 
 
 16 
 
 1521 
 
 156 
 
 
 744.1 
 
 526 
 
 2.1 
 
 25 
 
 4 
 
 .41 625 
 
 
 52. S 
 
 753.3 
 
 504 
 
 11.3 
 
 3 
 
 127 
 
 .69 9 
 
 
 33.9 
 
 747.1 
 
 440 
 
 5.1 
 
 61 
 
 26 
 
 .01 3721 
 
 311.1 
 
 
 742.9 
 
 469 
 
 .9 
 
 32 
 
 
 .81 1024 
 
 28.8 
 
 
 739.5 
 
 409 
 
 2.5 
 
 92 
 
 6 
 
 .25 8464 
 
 
 230 
 
 743.9 
 
 432 
 
 1.9 
 
 69 
 
 3 
 
 .61 4761 
 
 131.1 
 
 
 744.3 
 
 493 
 
 2.3 
 
 8 
 
 5 
 
 .29 64 
 
 18.4 
 
 
 747.8 
 
 436 
 
 5.8 
 
 65 
 
 33 
 
 .64 4225 
 
 377 
 
 
 740 
 
 537 
 
 2 
 
 36 
 
 4 
 
 1296 
 
 72 
 
 
 7.55 
 
 486 
 
 13.1 
 
 15 
 
 171 
 
 .61 225 
 
 196.5 
 
 
 
 
 
 
 1157 
 
 .93 46883 
 
 2876.9 
 
 1185. V 
 
 
 
 
 
 
 
 1185.7 
 
 
 
 
 
 
 
 
 1691.2 
 
 
 ff _ /1157.93 
 
 .9 
 
 
 /468S3 
 
 44 2 
 
 
 
 \ 24 
 
 
 ffr ~^ 24 
 
 
 2 (ay) = 1691.2 
 
 Coefficient 
 
 of Correlation 
 
 2( 
 
 / t 
 
 1691.2 
 
 72 =- 23 
 
 \ 
 
 Nov 
 
 '* 
 
 24X6.9X44 
 
 
 E 
 
 legressic 
 
 
 
 .23<r, 
 
 -.17 
 
 
 
 >n 
 
 *i 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE XIV C, 7 A. M. 
 
 Barometer 
 Millimetres 
 
 739 
 
 Carbon 
 Dioxide 
 Milligrams x 
 
 406 3.8 
 
 y 
 5 
 
 X 2 
 
 14,44 
 
 Products [xy] 
 y Negative Positive 
 
 25 19 
 
 746 
 
 419 
 
 3.2 
 
 18 
 
 10.24 
 
 324 
 
 57.6 
 
 745.1 
 
 422 
 
 2.3 
 
 21 
 
 5.29 
 
 441 
 
 48.3 
 
 726.2 
 
 390 
 
 16.6 
 
 11 
 
 275.56 
 
 121 
 
 182.6 
 
 721 
 
 397 
 
 21.8 
 
 4 
 
 475.24 
 
 16 
 
 87.2 
 
 742.1 
 
 382 
 
 .5 
 
 19 
 
 .25 
 
 361 
 
 9.5 
 
 740 
 
 419 
 
 2.8 
 
 18 
 
 7.84 
 
 324 50.4 
 
 
 736 
 
 390 
 
 6.8 
 
 11 
 
 46.24 
 
 121 
 
 74.8 
 
 737.1 
 
 393 
 
 5 .7 
 
 8 
 
 32.49 
 
 64 
 
 45.6 
 
 741.3 
 
 394 
 
 1 .5 
 
 7 
 
 2.25 
 
 49 
 
 10.5 
 
 743.5 
 
 410 
 
 .7 
 
 9 
 
 49 
 
 81 
 
 6.3 
 
 742.3 
 
 449 
 
 .5 
 
 48 
 
 .25 
 
 2304 24 
 
 
 732.5 
 
 406 
 
 10.3 
 
 5 
 
 106.09 
 
 25 51.5 
 
 
 751.5 
 
 390 
 
 8.7 
 
 11 
 
 75.69 
 
 121 
 
 95.7 
 
 751.4 
 
 383 
 
 8.6 
 
 18 
 
 73.96 
 
 324 
 
 154.5 
 
 753.9 
 
 363 
 
 11.1 
 
 38 
 
 123.21 
 
 1444 
 
 421.8 
 
 737.1 
 
 388 
 
 5 .7 
 
 13 
 
 32.49 
 
 169 74.1 
 
 
 751.2 
 
 398 
 
 8.4 
 
 3 
 
 70.56 
 
 9 25.2 
 
 
 746.5 
 
 402 
 
 3.7 
 
 1 
 
 13.69 
 
 1 
 
 3.7 
 
 748.2 
 
 364 
 
 5.4 
 
 37 
 
 29.16 
 
 1369 199.8 
 
 
 739.3 
 
 403 
 
 3 .5 
 
 2 
 
 12.25 
 
 4 7 
 
 
 745.5 
 
 402 
 
 2.7 
 
 1 
 
 7.29 
 
 1 
 
 2.7 
 
 743.7 
 
 406 
 
 .9 
 
 5 
 
 .81 
 
 25 
 
 4.5 
 
 749 
 
 396 
 
 6.2 
 
 5 
 
 38.44 
 
 25 31 
 
 
 739.8 
 
 409 
 
 3 
 
 8 
 
 9 
 
 64 24 
 
 
 747.9 
 
 422 
 
 5.1 
 
 21 
 
 26.01 
 
 441 
 
 107.1 
 
 758.8 
 
 423 
 
 16 
 
 21 
 
 256 
 
 441 
 
 336 
 
 1745.23 
 
 8693 506 
 
 1734.2 
 
 
 
 
 
 
 
 506 
 
 
 
 
 
 
 
 1228.2 
 
 <=, 
 
 11745. 
 
 23 =8 
 
 
 
 / =17 9 
 
 
 V 27 
 
 
 199S 9 
 
 V 27 
 
 Coffiecient of 
 
 Correlations 2 !^* = 
 
 1228.2 
 
 31 
 
 6 
 
 27X8X17.9 
 
 .316<r 2 
 
 Regression^ =.7 
 
 <*> 
 
 40-- 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 
 TABLE XV C, 12 
 
 M. 
 
 
 Barometer 
 Millimetres 
 
 749.1 
 
 Carbon 
 Dioxide 
 Milligrams x 
 
 390 - 4.2 
 
 y 
 24 
 
 X 2 
 
 17.64 
 
 576 
 
 Products [xy] 
 Negative Positive 
 
 100.8 
 
 746.2 
 
 409 
 
 2.9 
 
 - 5 
 
 8.41 
 
 25 
 
 14.5 
 
 742.5 
 
 403 
 
 - '.8 
 
 ill 
 
 .64 
 
 121 
 
 8.3 
 
 722.1 
 
 403 
 
 21.2 
 
 11 
 
 449.44 
 
 121 
 
 233.2 
 
 726.9 
 
 375 
 
 16.4 
 
 39 
 
 268.96 
 
 1521 
 
 639.6 
 
 742.5 
 
 387 
 
 .8 
 
 27 
 
 .64 
 
 729 
 
 21.6 
 
 740.1 
 
 381 
 
 - 3.8 
 
 i33 
 
 10.24 
 
 1089 
 
 105.6 
 
 736.1 
 
 362 
 
 - 7.2 
 
 52 
 
 51:84 
 
 2704 
 
 374.4 
 
 738.9 
 
 422 
 
 - 4.4 
 
 8 
 
 19.36 
 
 64 
 
 35.2 
 
 742.9 
 
 377 
 
 .4 
 
 37 
 
 .16 
 
 1369 
 
 14.8 
 
 745.1 
 
 386 
 
 1.8 
 
 28 
 
 3.24 
 
 784 
 
 50.4 
 
 739.9 
 
 403 
 
 - 3.4 
 
 11 
 
 11.56 
 
 121 
 
 37.4 
 
 732.9 
 
 386 
 
 10.4 
 
 28 
 
 108.16 
 
 784 
 
 291.2 
 
 745.8 
 
 380 
 
 2.5 
 
 34 
 
 6.25 
 
 1156 
 
 85 
 
 753.3 
 
 425 
 
 9.9 
 
 11 
 
 98.01 
 
 121 
 
 108.9 
 
 749.3 
 
 402 
 
 6 
 
 12 
 
 36 
 
 144 
 
 72 
 
 753.6 
 
 427 
 
 10.2 
 
 13 
 
 106.09 
 
 169 
 
 133.9 
 
 747.5 
 
 396 
 
 4.2 
 
 18 
 
 17.64 
 
 324 
 
 75.6 
 
 748.1 
 
 459 
 
 4.8 
 
 45 
 
 23.04 
 
 2025 
 
 216 
 
 747.9 
 
 442 
 
 4.6 
 
 28 
 
 21.16 
 
 784 
 
 128. S 
 
 740.1 
 
 438 
 
 - 3.2 
 
 26 
 
 10.24 
 
 676 
 
 83.2 
 
 744.1 
 
 474 
 
 .8 
 
 60 
 
 .64 
 
 3600 
 
 48 
 
 743.9 
 
 448 
 
 .6 
 
 34 
 
 .36 
 
 1156 
 
 20.4 
 
 749.8 
 
 449 
 
 6.5 
 
 35 
 
 42.25 
 
 1225 
 
 227.5 
 
 738.8 
 
 460 
 
 - 4.5 
 
 46 
 
 20.25 
 
 2116 
 
 207 
 
 752.9 
 
 468 
 
 9.6 
 
 54 
 
 92.16 
 
 2916 
 
 518.4 
 
 758.4 
 
 422 
 
 15.1 
 
 8 
 
 228.01 
 
 64 
 26484 
 
 120.8 
 
 1652.08 
 
 622.9 3350.5 
 
 
 
 
 
 
 
 622.9 
 
 2627.6 
 
 11652.08 _ 
 ffl ~ \ 27~ ~i 
 
 J 26484 
 27 
 
 =31.3 
 
 Coefficient of Correlations 
 
 2627.6 
 
 _____ s .39 
 
 27X7.8X31.3 
 
 .39cr 2 
 Regression^ -- = 1.5 
 
 41 
 
Relation of Carbon Dioxide Excretion to Barometric Change. 
 TABLE XVI C, 5 P. M. 
 
 Carbon 
 Barometer Dioxide x 
 Millimetres Milligrams 
 
 739.1 447 2. 
 
 9 
 
 y 
 20 
 
 x' 2 
 8.41 
 
 y 2 
 400 
 
 Products [xy] 
 Negative Positive 
 
 58 
 
 747, 
 
 .1 
 
 409 
 
 5, 
 
 ,1 
 
 18 
 
 26 
 
 .01 
 
 324 
 
 91.8 
 
 
 
 741.1 
 
 428 
 
 t , 
 
 ,9 
 
 1 
 
 
 .81 
 
 1 
 
 .9 
 
 
 
 718. 
 
 ,2 
 
 390 
 
 23. 
 
 8 
 
 37 
 
 566 
 
 .44 
 
 1369 
 
 
 880. 
 
 5 
 
 738. 
 
 1 
 
 419 
 
 3. 
 
 9 
 
 8 
 
 15 
 
 .21 
 
 64 
 
 31.2 
 
 742. 
 
 5 
 
 456 
 
 
 5 
 
 29 
 
 
 .25 
 
 841 
 
 
 14. 
 
 5 
 
 739 
 
 
 374 
 
 - 3 
 
 
 53 
 
 
 9 
 
 2809 
 
 
 159 
 
 
 737. 
 
 5 
 
 438 
 
 - 4. 
 
 5 
 
 11 
 
 20 
 
 .25 
 
 121 
 
 49.5 
 
 
 
 740 
 
 
 473 
 
 2 
 
 
 46 
 
 
 4 
 
 2116 
 
 92 
 
 
 
 744. 
 
 1 
 
 422 
 
 ' 2. 
 
 1 
 
 5 
 
 4 
 
 .41 
 
 25 
 
 10.5 
 
 
 
 745 
 
 
 448 
 
 3 
 
 
 21 
 
 9 
 
 
 441 
 
 
 63 
 
 
 744. 
 
 1 
 
 396 
 
 2. 
 
 1 
 
 31 
 
 4 
 
 .41 
 
 961 
 
 65.1 
 
 
 
 739. 
 
 1 
 
 476 
 
 2. 
 
 9 
 
 49 
 
 8 
 
 .41 
 
 2401 
 
 142.1 
 
 
 
 732. 
 
 9 
 
 411 
 
 - 9. 
 
 1 
 
 16 
 
 82 
 
 .81 
 
 256 
 
 
 145. 
 
 6 
 
 746 
 
 
 448 
 
 4 
 
 
 21 
 
 16 
 
 
 441 
 
 
 84 
 
 
 756. 
 
 2 
 
 473 
 
 14. 
 
 2 
 
 46 
 
 201 
 
 .64 
 
 2116 
 
 
 653. 
 
 2 
 
 744. 
 
 1 
 
 337 
 
 2. 
 
 1 
 
 90 
 
 4 
 
 .41 
 
 8100 
 
 180.9 
 
 
 
 747. 
 
 1 
 
 437 
 
 5. 
 
 1 
 
 10 
 
 26 
 
 .1 
 
 100 
 
 
 51 
 
 
 742. 
 
 9 
 
 435 
 
 
 9 
 
 8 
 
 
 .81 
 
 64 
 
 
 7. 
 
 2 
 
 739. 
 
 5 
 
 429 
 
 2. 
 
 5 
 
 2 
 
 6 
 
 .25 
 
 4 
 
 5 
 
 
 
 743. 
 
 9 
 
 419 
 
 1. 
 
 9 
 
 8 
 
 3 
 
 .61 
 
 64 
 
 35.2 
 
 
 
 744. 
 
 3 
 
 434 
 
 2. 
 
 3 
 
 7 
 
 5 
 
 .29 
 
 49 
 
 
 16. 
 
 1 
 
 747. 
 
 9 
 
 429 
 
 5. 
 
 8 
 
 2 
 
 33 
 
 .64 
 
 4 
 
 
 11. 
 
 6 
 
 740 
 
 
 429 
 
 2 
 
 
 2 
 
 4 
 
 
 4 
 
 4 
 
 
 
 755. 
 
 1 
 
 428 
 4 
 
 13. 
 
 1 
 
 1 
 
 171 
 
 .61 
 
 1 
 
 23076 
 
 
 13. 
 
 1 
 
 1232.69 
 
 805. 
 
 2130. 
 
 i 
 
 
 
 
 
 
 
 
 
 
 
 805 
 
 
 r-V 
 
 1325.1 
 
 _= 7.02 
 25 
 
 123076 
 
 =30.38 
 
 2 (xy) =1325.1 
 
 Coefficient of Correlation= x " =; _ _ =+.248 
 
 N<rV* 25X7.02X30.38 
 
 . 248<r a 
 Regression= =1.07 
 
 [2 
 
The results of the whole series of experiments are summed up in 
 Table XVII. 
 
 TABLE XVII. 
 
 General Summary. 
 
 Sub- 
 
 
 
 
 1 
 
 1 
 
 ject 
 
 Hour 
 
 X 2 
 
 y' 2 
 
 W 
 
 <?i 
 
 <T 2 
 
 , . Coeffic'nt 
 S(xy) ofeorre- 
 
 Probable 
 error 
 
 Regres- 
 sion 
 
 
 1 
 
 
 
 I 
 
 
 lation, r 
 
 
 
 A 
 
 7 A.M. 
 
 1,754.7 
 
 24,951 
 
 29 
 
 Y.8 |29.3 
 
 868. +0.12 
 
 0.13 
 
 0.45 
 
 A 
 
 12 M. 
 
 1,642.4 
 
 27,078 
 
 28 
 
 7.65 
 
 31.1 
 
 1,574.6 +0.236 
 
 0.126 
 
 0.95 
 
 A 
 
 5 P.M. 
 
 1,315.71 
 
 17,620 
 
 24 
 
 7.4 
 
 27.1 
 
 589.9 
 
 0.12 |0.126 
 
 0.44 
 
 B 
 
 7 A.M. 
 
 1,324.02 
 
 59,721 
 
 24 
 
 7.4 
 
 49.8 
 
 1,787.7 
 
 0.2 
 
 0.129 
 
 ! 0.13 
 
 B 
 
 12 M. 
 
 1,313.02 
 
 40,919 
 
 26 
 
 6.9 
 
 44.2 
 
 818.3 
 
 0.04 
 
 0.124| 0.09 
 
 B 
 
 5 P.M. 
 
 1,158.7 
 
 46,883 
 
 25 
 
 6.5 64.0 
 
 1,926.1 
 
 0.23 
 
 0.13 
 
 0.17 
 
 C 
 
 7 AJ.M. 
 
 1,228.2 
 
 8,693 
 
 27 
 
 8.0 
 
 17.9 
 
 1,228.2 
 
 +0,316|Q.12 
 
 0.7 
 
 C 
 
 12 M. 
 
 1,652.0 
 
 26,484 
 
 27 
 
 7.8 131.2 
 
 2,627. 6,+0. 39 
 
 0.11 
 
 1.5 
 
 C 
 
 5 P.M. 
 
 1,232.6 
 
 23,076 
 
 25 7. 02)30.38 
 
 1,325. 1|+0. 248 
 
 0.125 
 
 1.07 
 
 Conclusions : 
 
 There were indications in this work of an influence of barometric 
 change on carbon dioxide excretion in the case of one subject, C, since 
 there were three positive coefficients of correlation having the value of 
 C.316, 0.39, and 0.248, for morning, noon and evening experiments (per- 
 fect correlation would be indicated by a coefficient of 1) ; a slight direct 
 influence is also indicated in the case of A, whose coefficients were 0.12, 
 0.236 and 0.12. In the case of B, whose values of carbon dioxide ex- 
 cretion throughout the work were quite irregular, (See Table XVIII) 
 there were three negative coefficients with values of 0.2, .04 and 
 .23, respectively. 
 
 43 
 
TABLE XVIII. 
 
 Carbon Dioxide 
 
 Excretion in 
 Milligrams per 
 Minute 
 
 A. M. 
 
 ABC 
 Cases Cases Cases 
 
 M P. M. A. M. M. P. M. A M. 
 
 P. M. 
 
 361 370 
 
 
 
 
 
 
 
 
 I 2 
 
 1 
 
 
 371 380 
 
 
 
 I 
 
 I 
 
 
 
 1 
 
 1 
 
 3 
 
 1 
 
 381 390 . . 
 
 
 
 i 
 
 1 
 
 
 
 5 
 
 5 
 
 1 
 
 391 400 
 
 
 
 1 
 
 1 
 
 
 
 6 
 
 1 
 
 1 
 
 401410 
 411 420 
 
 4 
 3 
 
 1 
 
 2 
 
 2 
 
 2 
 
 
 1 
 
 8 
 2 
 
 5 
 1 
 
 1 
 3 
 
 421' 430 
 
 5 
 
 2 
 
 4 
 
 
 3 
 
 
 3 
 
 3 
 
 5 
 
 431 440 
 
 4 
 
 5 
 
 3 
 
 2 
 
 1 
 
 3 
 
 
 1 
 
 4 
 
 441 450 
 
 2 
 
 3 
 
 17 
 
 1 
 
 4 
 
 
 1 
 
 3 
 
 3 
 
 451 46Q 
 
 2 
 
 4 
 
 1 
 
 2 
 
 4 
 
 
 
 1 
 
 1 
 
 461 470 
 
 5 
 
 4 
 
 2 
 
 1 
 
 2 
 
 3 
 
 
 2 
 
 
 471 480 
 
 1 
 
 3 
 
 
 
 2 
 
 1 
 
 
 1 
 
 3 
 
 481 480 
 
 
 3 
 
 
 2 
 
 1 
 
 1 
 
 
 
 
 491 500 
 
 1 
 
 1 
 
 2 
 
 
 2 
 
 2 
 
 
 
 
 501 510 
 
 1 
 
 
 
 2 
 
 2 
 
 2 
 
 * 
 
 
 
 
 11 520 
 
 
 1 
 
 
 2 
 
 
 2 
 
 
 
 
 521 530 
 
 
 
 
 2 
 
 2 
 
 1 
 
 
 
 
 531 540 
 
 
 
 
 2 
 
 1 
 
 21 
 
 
 
 
 547 550 
 
 
 
 
 1 
 
 1 
 
 3 
 
 
 
 
 551 560 
 
 
 1 
 
 
 
 1 
 
 1 
 1 
 
 
 
 
 561 570 
 
 
 
 
 
 1 
 
 i 
 
 
 
 
 
 
 
 
 
 
 1 
 
 
 
 
 These results are, perhaps, what might have been expected. The 
 barometric change is evidently a minor influence and its effect is 
 therefore liable to be masked by other influences, such as exercise, 
 amount and character of meals, etc. Moreover, the effect of varying 
 barometric pressure upon the muscular endurance noted by Prof. Lom- 
 bard in his own case has not been verified in the case of other sub- 
 jects. The writer is of the opinion that if a series of parallel ergo- 
 graphic and respiration experiments were made on a number of sub- 
 jects, it would be found, in general, that positive effects of barometric 
 changes on muscular endurance are accompanied by positive cofficients 
 of correlation of barometric change with rate of excretion of carbon 
 dioxide. 
 
 44 
 
VI. THE EXCRETION OF CARBON DIOXIDE DURING UNI- 
 FORM MUSCULAR WORK, AND ITS RELATION TO THE 
 SECONDARY RISE OF THE PULSE RATE, 
 
 1. Method. 
 
 About twenty experiments were made to find the general cours? 
 of the changes in rate of excretion of carbon dioxide resulting from 
 work. The work was done on the bicycle with stationary frame. This 
 is driven by the subject at a uniform rate which is continuously record- 
 ed. The graphic record of carbon dioxide excretion is taken on a slowly 
 revolving drum along with records of respiratory movements, revolu- 
 tions of the bicycle crank shaft, and time in seconds. On a loop of pa- 
 per passing around two drums and moving more rapidly, the pulso 
 is recorded along with a time curve, giving seconds. 
 
 By means of a Morse key and an electric signal on each drum, the 
 corresponding parts of the two records are indicated. 
 
 In beginning an experiment, the subject puts on the mask, mounts 
 the wheel, the pneumograph and pulse tambour are adjusted and test- 
 ed, and then the mask is connected to the tubes leading to the apparat- 
 us for determining carbon dioxide. The drums are started, and the 
 subject sits quietly on the bicycle until sufficient length of record has 
 been made to show the normal rate of pulse, breathing, and excretion 
 of carbon dioxide. Then, at a signal from the experimenter ho begins 
 to drive the wheel in unison with a metronome placed before him, and 
 the records continue. The balance is handled as described in the pre- 
 ceding section. The electric signal connected with the bicycle indi- 
 cates the moment of starting and stopping, and the speed of revolution. 
 On cessation of the work the records continue until the rate of excre- 
 tion has returned approximately to what it was before the work began, 
 as indicated by the slant of the line described by the recording lever. 
 The experiment then ends. A record taken in this way is shown in 
 Pig. 7. 
 
 Figure? -Graphic iccord of carbon dioxide excretion during bicycling. To be read from 
 left to right. K, respiratory movements. CO2 record made by chemograph. The descending 
 lines, as AC, are due to accumulation of carbon dioxide in the absorbing apparatus. The as. 
 cending lines, as C 1, form no proper part of the curve but are due to addition of weights by the 
 operator. T is the time marked every 10 seconds. M, revolutions of bicycle crank. 
 
Pulse rate 
 per minute 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10S 
 
 
 
 
 
 
 
 
 
 
 j 
 
 
 1 
 
 
 
 (*ftt 
 
 
 
 
 
 
 
 
 I 
 
 3 
 
 ^ 
 
 i 
 
 ~^~~ 
 
 r^j 
 
 
 
 f-U2 
 
 <Y, 
 
 
 
 rVS 
 
 A> 
 
 W 
 
 C 
 
 E 
 
 
 
 
 
 | 
 
 
 
 CMS 
 
 
 
 r 
 
 
 
 
 
 
 
 
 
 
 _^ 11 
 
 
 
 1 *5 
 
 
 
 
 I 
 
 
 
 
 
 
 
 
 
 ju 
 
 
 
 2 ft 
 
 
 
 
 1 
 
 
 
 
 
 
 
 
 
 \f 
 
 -"Xi 
 
 f 
 
 21 
 
 
 
 / 
 
 
 
 
 
 
 
 
 
 
 1 
 
 
 \> 
 
 (.4. 
 
 
 
 / 
 
 
 
 
 
 
 
 
 
 
 
 \ r 
 
 
 O 7 
 
 fin 
 
 
 j 
 
 
 
 
 
 
 
 
 
 
 1 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 : 
 
 J, 
 
 
 \4 
 
 h ( 
 
 FIGURES. lotted curves of pulse rate and of carbon dioxide exc-etioti from same 
 experiment as figure 7. Broken line, pulse rate; solid line, carbon dioxide excretion. 
 Ordinates give pulse rate per minute and grams of carbon dioxide per minute. 
 
 2. Results. 
 
 This figure shows in a general way, the effect of the work on the 
 excretion of carbon dioxide. Beginning at the left, the nearly straight 
 slanting line, A.B., drawn by the writing lever of the chemograph indi- 
 cates the rate of excretion during rest. Then when work begins, the in- 
 creased slant of B. C. indicates- an increased excretion, and this increase 
 continues for about two minutes. From this time to the end of the work- 
 ing period the slant of the line remains about the same, indicating uni- 
 form excretion of carbon dioxide. As soon as work stops there is an 
 immediate change in the slant D. E., showing the diminished excre- 
 tion. 
 
 A more accurate idea of the changes in question can be obtained 
 from Pig. 8, which was obtained frcm the record of Pig. 7, by careful 
 measurements and plotting. This figure also contains the plotted 
 curve of pulse rate. The pulse curve shovs plainly a rapid primary 
 rise, a. b.; a plateau, b. c.; and a slow secondary rise. The curve of car- 
 bon dioxide rises rather rapidly during the first two minutes, which 
 Incudes the period of rapid rise of pulse rate and a part of the plateau. 
 During the remainder of the working period tne rate of excretion is 
 seen to be practically constant, 2ia although the pulse rate is rising 
 for the latter half of the time. On cessation of work the excretion 
 diminishes, until at the end of two minutes it has returned to practi- 
 cally the original rate. At the same time the pulse rate, although 
 falling rapidly at first (de) is oscillating about a rate (ef) 20 per cent 
 above the normal. 
 
 (c) Discussion of Results: 
 
 A comparison of the curves of pulse rate and carbon dioxide then, 
 shows that the primary rise of pulse frequency coincides in time ap- 
 proximately with the rise in excretion of carbon dioxide, and the same 
 can be said of the corresponding fall. The short latent period of the 
 pulse shows, as has been stated by Bowenf, that if the increased pro- 
 
 tloc. cit. 
 
 -46- 
 
duction of carbon dioxide is in any way responsible, even in part, for 
 the change in pulse rate when work begins, the influence must be 
 brought to bear through nervous channels, rather than as a direct ef- 
 fect of the gas upon the heart itself or upon the cardiac centers. There 
 seems to be no reason why the prompt increase in heart action may 
 not be due in part at least to sensory impulses arising in the muscles 
 as a result of the waste products suddenly set free there as advocated 
 by Anthanasiu 38 . 
 
 The results, obtained, then, show no evidence of any relation of 
 cause and effect between the production of carbon dioxide, and the sec- 
 ondary rise in pulse rate. In Fig. 8 it is seen that the excretion of 
 carbon dioxide is constant during the entire period of the secondary 
 rise of pulse rate, while the secondary fall of pulse rate during recovery 
 is continued after the rate of excretion of carbon dioxide has returned 
 to the normal. The lack of correspondence in the two curves practical- 
 ly amounts to a demonstration that the secondary changes in pulse rate 
 have nothing to do with the production of carbon dioxide and its elim- 
 ination from the system. 
 
 VII. THE LATENT PERIOD OF CARBON DIOXIDE EXCRETION 
 
 Method: 
 
 A number of experiments were made to determine how soon after 
 work begins the increase in production of carbon dioxide begins to show 
 itself in the expired air. Fig. 9 shows a group of records taken in the 
 course of these experiments. The procedure is as follows: The subject, 
 sitting quietly on the bicycle, breathes into the apparatus for about 
 30 seconds, the rate of excretion of carbon dioxide being recorded 
 on the drum, giving the line m. n. in curve A. He then 
 begins driving the bicycle, the time of starting being accurately in- 
 dicated by marker M. The experiment continues only long enough to 
 show a definite increase in the excretion of carbon dioxide resulting 
 from the work.' After fixing the record in shellac, the point n on the 
 curve of carbon dioxide, where the line first changes its direction as 
 the result of the work, is revolved to the base line with a radius equal 
 tc the length of the long arm of the writing lever, so as to avoid error 
 due to rotation of the lever on its axis. Now the number of seconds 
 between the beginning of work and the resulting change in excretion of 
 carbon dioxide can be readily obtained from the time record, T. 
 
 To find the result desired we must deduct from the time found in 
 the manner just described, the time required for the passage of the ex- 
 haled air from the mouth and nostrils, through the mask and connect- 
 ing tubes to the chemograph, and sufficient additional time to collect in 
 the soda-lime enough carbon dioxide to overcome the inertia of the bal- 
 ance. The time to be deducted is found as follows: While sitting 
 
 47 
 
,81 
 
 *l=j 
 
 C o LT 
 
 48 
 
quietly upon the bicycle, with the record in progress, the subject holds 
 his breath for several seconds. The result is shown in Curve C of 
 Fig. 9. The pneumograph curve at the top of the record shows when 
 the breath is held. Scon the lever point which records the movement 
 of the balance changes its direction, finally writing the horizontal line 
 r V. When the subject begins to breathe again the pneumograph 
 curve shows the exact moment of the first expiration, and the time from 
 this point to the point V, where the carbon dioxide lever first begins to 
 fall again, is the time of delay due to the apparatus. Prom a large 
 number of tests this time was found to be close to 6 seconds. Since 
 this delay depends upon the rate at which air is drawn through the 
 apparatus by the suction pump, all of the experiments on latent period 
 were made with the air moving at the uniform rate of 20 litres per min- 
 ute. 
 
 2. Results. 
 
 Making the deduction of 6 seconds in the case in curve A of Pig. 
 9, values for the latent period were obtained varying all the way from 
 3 to 14 seconds. Now few of these results are long enough to corre- 
 spond with the time required for the carbon dioxide formed in the mus- 
 cles at the time of the first muscular contraction to reach the outside 
 air. It must first diffuse into the blood from the tissues where it is 
 formed, then traverse the venous half of the systemic circulation, the 
 right side of the heart, and the arterial half of the pulmonary circula- 
 tion, and finally diffuse into the air of the alveoli before any of it can 
 appear in the breath. From the latest conclusions of Stewart and oth- 
 ers who are considered as authorities on the time of the circulation, it 
 appears that from 15 to 20 seconds is the least possible time for the 
 blood to travel this distance, to say nothing of the diffusion time. We 
 must evidently account for the shortness of the latent period thus 
 found. 
 
 Careful study of the matter finally led to the conclusion that the 
 sudden change in rate of excretion of carbon dioxide on beginning 
 work was due primarily to a better ventilation of the lungs while the 
 continuation of the fall was due to the ventilation of the blood and tis- 
 sues as well. " l 
 
 A recognition of this fact led to the following modification of the 
 methods employed in the determination of the latent period of carbon 
 dioxide excretion. 
 
 After the "normal" rate of excretion had been obtained (A B, Fig. 
 9), the subject began forced breathing at a predetermined rate, contin- 
 uing this for a minute or so until the curve of carbon dioxide had ap- 
 
 49 
 
parently assumed its permanent direction. At this point, at a signal 
 from the experimenter, the subject began to drive the bicycle as in the? 
 preceding experiments. 
 
 Curve B of Fig. 9 shows the result in one instance. The effect of 
 the increased respiration is clearly marked, the new rate of excretion 
 qr being sharply denned from the normal rate (pq) preceding it. The 
 further increase on beginning work is not so prompt in its appearance 
 rnd comes on more gradually, reaching its maximum after a minute or 
 more, depending on the work. In these experiments the latent period 
 of increase due to the work was from seventeen to twenty-two sec- 
 onds. It is evident that as the latent period will vary with the rapidity 
 of the circulation, the rapidity of diffusion, and the rate of work, a 
 more definite figure is not to be expected. 
 
 Shortly after the publication of these results by Bowen and the 
 writer, a communication was received from Prof. N. Zuntz, calling at- 
 tention to the gradual character of the change in rate of excretion of 
 carbon dioxide after the beginning of work (as already mentioned) 
 and kindly suggesting a modification of the method of carrying out 
 the latent-period experiments. According to Prof. Zuntz, if the forced 
 breathing were continued for -five minutes instead of one minute, as al- 
 ready stated, the blood and tissues would become thoroughly ventilated; 
 the direction of the curve of carbon dioxide would become parallel to 
 that before forced breathing began; and furthermore, with the begin- 
 ning of work, the carbon dioxide curve, after the latent period of 
 twenty seconds, would change much more sharply than it did in the 
 published reocrd. The writer accordingly made a series of experi- 
 ments in which the forced breathing was continued for from five to 
 seven minutes before bicycle work has begun. 
 
 The results of one of these experiments are seen in Figure 10 in 
 which A is the pneumograph record, Pqrs the carbon dioxide curve, 
 T the chronograph record, and M the bicycle record. The line Pq' 
 as in the previous paper, 3 represents the rate of excretion before the 
 
 beginning of forced breathing; the line Pqq'q"r (broken by the arrest- 
 ing of the beam and the addition of four gram weights) represents 
 the curve of carbon dioxide during forced breathing; r is the position 
 on the curve of the carbon-dioxide-writing lever at the instant when 
 work was begun; and s is the point where the curve changes as a re- 
 sult of the work. 
 
 This research was conducted on two subjects. It was found very 
 difficult to maintain respiration of uniform depth for five minutes, 
 since there is a decided tendency to make the respiration shallower. 
 Indeed, notwithstanding the great care on the part of the subject, the 
 
 3 Higley and Bowen: Loc. cit. 
 
 50 
 
pneumograph record indicated, in some cases, a lessened depth of res- 
 piration toward the end of the forced respiration period. 
 
 In the case of one subject the curve for rate of excretion of carbon 
 dioxide returned, during the period of forced respiration, practically 
 to the original value. With the other subject the return was less per- 
 perfect. It would seem that as a result of the additional work of 
 the respiratory organs a return of the rate of excretion to the value 
 during normal respiration could not be expected. 
 
 While, therefore, the writer is able to confirm Prof. Zuntz's predic- 
 tion regarding the sharpness of the change, as a result of work, in the 
 curve of carbon dioxide after continued forced respiration, he can only 
 confirm in part Prof. Zuntz's prediction on the return of the curve 
 during forced respiration, to the direction which it had before forced 
 respiration was begun. 
 
 ' i ' 7 - i, '-A. 
 
 ' 
 
 -51 
 
CONCLUSIONS 
 
 1. The problem of finding the changes in rate of excretion of car- 
 bon 'dioxide resulting from muscular work and other causes is practi- 
 cally solved by the method used in this research. 
 
 2. The latent period of increase in excretion of carbon dioxide 
 from the lungs in case of beginning work is approximately twenty sec- 
 onds, and the increase reaches its maximum in about two minutes. 
 
 3. The rate of excretion of carbon dioxide from the lungs is prac- 
 tically uniform from minute to minute during uniform muscular work, 
 after the blood has had time to take part fully in the process of elim- 
 ination. 
 
 4. Upon cessation of work the excretion of carbon dioxide de- 
 creases to the normal amount in about the time occupied by its in- 
 crease, and after a like latent period. 
 
 5. The results obtained show no indication of any connection of 
 cause and effect between the production and elimination of carbon di- 
 oxide and the secondary rise of pulse rate. 
 
 GENERAL SUMMARY 
 
 1. In the balance-chemograph we have an apparatus which will oe 
 of service in a study of the rate of change of a number of chemical 
 reactions. 
 
 2. The respiration apparatus of which the chemograph forms a 
 part can be employed with advantage in a study of the character of 
 all important changes in the rate of excretion of carbon dioxide from 
 the lungs; furthermore, with this apparatus the analyses and calcula- 
 tions that are necessary in experiments on the respiration, are greatly 
 simplified. 
 
 3. The average carbon dioxide excretion per kilogram of body 
 weight per minute in the case of 24 normal subjects, at a time averag- 
 ing four hours after the midday meal was .0063 grams. This agrees 
 well with values obtained by Johannsen and Magnus-Levy. 
 
 4. The daily curve of metabolism is affected by the time of tak- 
 ing the heartiest meal. Indigestion, catarrhal infection and thorough 
 athletic training increased the rate of excretion and the presence in the 
 body of the subject of a large amount of adipose tissue diminished the 
 rate of excretion. 
 
 5. A series of experiments made daily, morning, noon and even- 
 ing, for five weeks, seems to show that with some subjects the carbon 
 dioxide excretion varies with the barometric height. This result is 
 in harmony with results obtained by Lombard on the effect of barom- 
 etric changes on muscular endurance. 
 
6. By the use of the respiration apparatus described in this paper 
 the rate of change of carbon dioxide excretion from a condition of 
 rest through a period of uniform muscular work and the period of re- 
 covery has been worked out. This curve is markedly different at 
 important points from the corresponding pulse curve as worked out by 
 Bowen. The secondary rise in the pulse rate is not due to the pres- 
 ence of an increased amount of carbon dioxide in the blood. 
 
 7. The latent period of carbon dioxide excretion as a result of 
 vigorous work is about 20 seconds. 
 
 8. After a period of forced respiration lasting five minutes, the 
 curve of excretion of carbon dioxide nearly returns to the direction 
 which it had before forced respiration began; if now vigorous muscular 
 work be begun, the curve of excretion of carbon dioxide shows a much 
 more sharp turn than in the case where the period of forced breathing 
 is much more brief. 
 
BIBLIOGRAPHY 
 
 1. Ostwald, Zeitschrift fur physikalische Chemie; (1900) XXX, 33. 
 204. 
 
 2. Bowen, Contributions to Medical Research, University of Mich- 
 igan, (1903) pp. 462-493. 
 
 3. Loewy, Archiv fur den gesammten Physiologie. 
 
 4. Black, Lectures on Chemistry, Robinson, Edinburg, 1803. 
 
 5. Priestley Philosophical Transactions, London, (1772) Vol. 62, 
 pp. 147, 168. 
 
 6. Lavosier et Laplace, Histoire Academic Royal Science de 
 Paris. (1780) 355. Ouvres de Lavoisier. Tome II, 326. 
 
 6a. Haldane and Smith, Archiv fur Hygiene (1896) Bd. X. S. 367. 
 
 7. Hoppe-Seyler und Stroganow, Archiv fur den gesammten, 
 Physiologie, Bonn. (1876) XII, 18. 
 
 8. Pfluger und Colesanti, Ibid. (1877) XIV, 92. 
 
 9. Atwater and Benedict. Report International Congress of Phys- 
 ologists, 1904. 
 
 10. Scharling, Annalen der Chemie und Pharmacie (1843) Band, 
 XLV, S. 214. 
 
 11. Pettenkofer, Annalen der Chemie und Pharmacie (1862-3). 
 Supp. Band, II. S 17. 
 
 12. Tigerstedt, Skandanavisches Archiv der Physiologie (1895). 
 Bd. 6 S. 1. 
 
 13. Johanssen, Skandanavisches Archive der Physiologie (1901). 
 Band II, 273. 
 
 14. Atwater, United States Department of Agriculture Bulletin 
 63, (1899). 
 
 15. Jaquet, Verhandlungen der Naturwissenschaftlichen Gesell- 
 schaft in Basel. XII 18 (1903). 
 
 16. Pattersson und Hogland, Berichte der deutsche chemische 
 Gesellschaft (1889). 
 
 16a. Lavoisier und Seguin. Histoire Academic royal Science de 
 Paris, (1789) 185. 
 
 17. Speck, Physiologie des Menschlicen Atmens (1892) p. 95. 
 
 18. Geppert and Zuntz, Archiv for den gesammten Physiologie. 
 (1888) XLII, 196, Zuntz und Schumberg Physiologie des Marches S 209. 
 
 19. Hanriot and Richet Annales des chimie et de Physique 
 (1891) pp. 22, 495. 
 
 20. Higley and Bowen American Journal of Physiology (1904), 
 XII, 4, page 311. 
 
 21. Zuntz and Schumberg Loc. cit. S 208. 
 
 21a. Zuntz and Hagamann Stoffwechsel des Pferdes S. 2yu. 
 
 22. Zuntz, Pfluger's Archiv. (1897), 68, 191. 
 
 23. Johanssen, Skandanavisches Archiv fur Physiologie (1898) 
 8.85. 
 
24. Magnus-Lovy, Pfluger's Archiv (1893) 55, 1. 
 
 25. Sonden and Tigerstedt, Skandanavisches Archiv, fur Physiolo- 
 gie (1895), 6. 
 
 26. Vierordt. 
 
 27. Speck, Archiv fur experimental Pathologic und Pharmakolo- 
 Kie, (1874), 2. 
 
 28. Hanriot, Comptus Rendus, (1892) 114, 371. 
 
 29. Lombard, Journal of Physiology, (1892) XIII, pp. 1-58. 
 
 30. Athanasieu and Carvallo, Archives de physiologic, (1898) pp. 
 554, 567. 
 
 31. Ewald, Pfluger's Archiv VII, 575. 
 
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