GIFT OF Mrs. John B, Casserly THE EEASON WHY: A CAREFUL COLLECTION OF MANY HUNDREDS OF REASONS FOR THINGS WHICH, THOUGH GENERALLY BELIEVED, ARE IMPERFECTLY UNDERSTOOD. A BOOK OF CONDENSED SCIENTIFIC KNOWLEDGE FOK THE MILLION. THE AUTHOR OF "INQUIRE WITHIN.-" This collection ol useful information on " Common Things " is put in the interesting form of " Why and Because," and comprehends a familiar explanation of many sub. iects which occupy a large space in (he philosophy of Nature, relating to air, cnlmals, atmosphere, caloric, chemistry, ventilation, materia medica, meteorology, acoustic*, eloctrjcity, light, zoology, etc. NEW YORK : DICK & FITZGERALD, PUBLISHERS, No. 18 ANN STBEET. PREFACE. WE are all children of one Father, whose Works it should be our delight to study. As the intelligent child, standing by his parent's knee, asks explanations alike of the most simple phenomena, and of the most profound problems ; so should man. turning to his Creator, continually ask for knowledge. JNot because the profession of letters has, in these days, become a fashion, and that the man of general proficiency can Dest work out his success in worldly pursuits ; but because knowledge is a trea- sure which gladdens the heart, dignifies the mind, and ennobles the soul. The occupation of the mind, by the pursuit of knowledge, is of itself a good, since it diverts from evil, and by elevating and refining the mind, and strengthening the judgment, it fortifies us for the hour of temptation, and surrounds us with barriers which the powers of sin cannot successfully assail. Tt is not contended that the mere acquisition of knowledge will either ensure a good moral nature, or convey rengious truth. But both religion and morals will find in the diffusion of knowledge a ground- work upon which their loftier temples may discover an acceptable foundation. The man who comprehends the order of Nature, and tht immutability of Divine law, must of necessity bring himself in some degree into accordance with that order, and under submission tc the law : hence the tendency of knowledge will always be found to harmonise the fragment with the mass, and to subvert the evil to the good. 756958 iv PBEFACE. The troubles of the world have arisen from the want of know- ledge, not frcm the possession of it. And in proportion as man becomes an intelligent and reflective being, he will be a better creature in all the relations of life. If these benefits, vast and incalculable as they are, be the real tendency and result of knowledge, why is ignorance allowed to remain, and \\by is the world still distracted by error? It is because the moral and intellectual qualities of man are, like all creations and gifts of God, the subjects of development, whose law is progression. We can aid human improi ement, but we cannot unduly hasten it. Whenever man has sprung too rapidly to a conclusion, he has alighted upon error, and has had to retrace his steps. The greatest philosophers have been those who have clung to the demonstrative sciences, and have held that a simple truth well ascertained, is greater than the grandest theory founded upon questionable premises. Newton made more scientific revelations to mankind than any other philosopher ; and his discoveries have borne the searching test of time, because he snatched at nothing, leaped over no chasm to establish a favourite dogma ; but, by the slowest steps, and by regarding the merest trifles, as well as the highest phenomena, he learnt to read Nature correctly. He discovered that her atoms were letters, her blades of grass were words, her phenomena were sentences, and her complete volume a grand poem, teaching on every page the wisdom and the power of an Almighty Creator. When he observed an apple fall to the ground, he asked the "Reason Why;" and in answer to that enquiry, there came one of the grandest discoveries that has ever been recorded upon the book of science. With that discovery a flood of light burst upon the human mind, illustrating in a far higher degree than had ever previously been conceived, the vastness of Almighty Power. Why should not each of us enquire the " Eeason Why " regarding everything that we observe? Why should we men- PREFACE. tally grope about, when we may see our way? When addressed in a foreign tongue, we hear a number of articulated sounds, to which we can attach no meaning ; they convey nothing to the mind, make no impression upon the indwelling soul. When those sounds are interpreted to us, in a language that \ve can understand, tbey impart impressions of joy, hope, surprise, or sorrow, because the words convey to us a meaning. In like manner, if we fail to understand Nature, its beauties, its teachings are lost. Everything speaks to us, but we do not understand the voices. They come murmuring from the brook, trilling from the bird, or pealing from the thunder; but though they reach the ear of the body, they do not impress the listening spirit. Every flower, every ray of light, every drop of dew, each flake of snow, the curling smoke, the lowering cloud, the bright sun, the pale moon, the twinkling stars, speak to us in eloquent lan- guage of the great Hand that made them. But millions lose tho grand lesson which Nature teaches, because they can attach no meaning to what they see or hear. " THE REASON WHY" is offered as an interpreter of many of Nature's utterances. Great care has been taken that these in- terpretations may be consistent with the latest knowledge, obtained from the highest sources. If the author finds that his work i. c accepted for the good of those who seek not only to know, but to understand, he will make it his constant care to read the Book of Nature, and to add to the pages of this volume whatever interpretations the progress of enquiry and discovery may demand and supply. INDEX, AND INDEX LESSONS. ^^^ The numbers refer to the Questions. The Index Lessons do not cor* respond with the Chapters, but are designed to bring together in their alpha* betical connection, all the Questions and Answers upon each particular subject included in the work. LESSON III. Air, which is heavier, dry or va- porised 697 Air-pistol (or pop-gun), why does pressure applied to the handle propel the cork 854 Air-pistol, why must the handle be drawn out before the cork is placed iu 855 Air, why does fresh impart a healthy appearance 915 Albumen, what is it 899 Alkalies, what are they 36 Amber, or electrum, what is it ... 564 Animals, how is their greater warmth in winter provided for 168 Animal forms, why are there so many 1029 Animal furs, why do they become thicker in the winter 1035 Animals, why have carnivorous, long pointed teeth 1038 LESSON IV. Animals with long necks, why have they large throats 1049 Animals, why cannot flesh-eaters live upon vegetables 1071 Animals, why can ruminating recover the food from their paunches 1089 Animals, why can ruminating keep the chewed from the un- chewed food in their stomachs 1090 Animals, why do the smaller animals breed more abundantly than the larger ones 1094 Animals, domestic, why may change of weather be expected when they are restless 1107 Animals, plants, and minerals, what are thv differences between them 1140 Animals that graze, why do they crop the tender blades, but leave the tall grass 1S87 LESSON I. Acids, vegetable, whence are they obtained 1256 Actinism, what is it 552 Actinism, what effect has it upon vegetation 559 Actinism, at what season of the year is it most abundant ... 560 Aerial spectra, what is the cause of 527 Affinity, what is the attraction of 777 Air, why do we breathe it ... ... 4 Air, what is the composition of it 12 Air, what is its state after it has been breathed 13 Air, is that sent from the lungs light or heavy 14 Air, is it a good or bad conductor of heat 150 Air, why is a still summer said to be sultry 171 Air, why does it feel cooler when in motion, than when still ... 175 LESSON II. Air, when is it hot enough to des- troy life 179 Air, why is it often excessively hot in chalk districts 219 Air, is it heated directly by the sun's rays 221 Air, why does it ascend the chim- ney 240 Air, why does it fly through the doors and windows towards the fire place 241 Air, what does the motion of it in our rooms illustrate 242 Air, why does it become charged with watery vapour 346 Air, when is it said to be saturated with vapour 430 Air, what proportion of water is air capable of holding in the form of vapour 431 Air, what is its weight relative to that of water 647 QUESTIONS FOBMING A COMPLETE INDEX. LESSON V. Animals, distribution of 132 Arms and hands, why do we see blue marks upon them 89 Arms and legs, why does it require the influence of the will to set them in motion 917 Arms and legs, why are they made subject to the will 919 Ascending, what is the cause of bodies 775 Atmosphere, how is it heated ... 23:. Atmospheric humidity, why does it sometimes form clouds, at others form dews, fogs, mists, &c. 409 Atmospheric pressure, how high will it raise water 65; Atmosphere, what is the 639 Atmosphere, to what height does it extend 639 Atmosphere, what is the amount of its pressure 641 Atmosphere, what is the propor- tion of watery vapour in the ... 642 Atmosphere, why are its upper regions intensely cold 441- Atmosphere, what is the greatest height ever reached in the ... 618 LESSON VI. Atmospheric pressure, what is the total amount on the earth's surface 644 Atmosphere, what is the amount of its pressure upon t he human body 645 Atmosphere, why do we not feel its pressure 646 Atmosphere, to what extent may its pressure vary 702 Attractive agent, what is an ... 7irds, why have water- fowls feathers of a close and smooth texture 1033 irds, why are they covered with feathers 1030 irds, why does black down grow under their feathers on the approach of winter 1036 irds, why have they hard beaks 104U iirds, why are their beaks generally long and sharp ...1041 lirds, #hy are their bones hollow 1060 !irds, why do they 'ay eggs ... 1051 QUESTIONS FOBMING A. COMPLETE INDEX. LESSON IX. Birds, why have those with long legs short tails ... 1052 Birds, why have aquatic web- feet .- 1059 Birds why have those that swim and dive short legs ... ... 1060 Birds, why have some deep rough notches on the under surfaces of their feet ... .., 1061 Birds, why have they gizzards ... 1072 jiinlsofprey why have they no gizzards 1084 Birds, why may wet and thunder be expected when they cease to sing .. ... ' 1121 Birds of passage, why, if they arrive early, may severe weather be expected 1121 Birds geological distribution of... 1326 Jirds, tameness of in unfrequented countries ... ... 1327 Birds, why are birds of song not also remarkable as birds of Bud^w^fat are the" velocities of their flights ... 1329 Birds, what is the cause of their migrations 1330 Blaci, why should parts of kettles an QUESTIONS FOKMING A COAIPLKTE INDEX. XVH LESSON XLI. Hydrogen-gas, what proportion is dangerous if inhaled ... ... 67 Hydrogen-gas, what proportion may be recognised by its smell 68 Hydrogen-cas, may the use of it be considered dangerous ... 70 Hydrogen-gas, what sources of it are there in our dwellings ... 69 Hydrogen, why will it burst into flame when coals become heated 100 Hydrogen, why does bi-carburet- ted burn with a whiter flume than common coal-gas 281 Ice, why are blocks of it wrapped in flannel in summer time ... 154 Ice, why does it melt ... ... 325 Icn, why does it occupy more space than water 752 Ignis fatuus, what is it 318 Incidence, what is the line of ... 519 Incidence, what is the angle of ... 521 India-rubber, where is it obtained 1254 Infants, why have they no teeth ... 1070 Insects, why have they a large number of eyes 1083 Insects, why have they long pro- jections from their heads ... 1100 Insects, why do they attach their eggs to leaves 1295 Insect', why do they multiply so numerously 1300 LESSON XL1I. Insects, what is a larva 1302 Insects, what is a pupa ... ... 1303 Insects, what is a chrysalis ... 1304 Insects, what u a nymph 1305 Insects, why do they abound in decaying substances and in pu- trid waters 1313 Insects, why do we see them in tanks of ruin-water 1314 Iron articles, why are they intense- ly cold in winter 132 Iron articles, why do they usually feel cool, even when near a fire 132 Ironing-box, why does the iron sometimes become too large for the box to receive it 335 Ironing-box, why does the iron en- ter ir, when partially cooled ... 336 Iron, why does it rust when wetted 768 Jew'a-harps, why do they give mu- sical sounds 851 Jew's-harps, why will they not produce loud sounds unless they are applied to the mouih 852 Jew's-harps, why does the altera- tion of the form of the mouth al- ter the sounds 853 Kangaroos and opossums, why hnve they pouches in which they carry their young ... 1139 LESSON XI.III. Kettle-holdurs, of what use are they ............... 128 Kettles and saucepans, why should the lids and fronts of, be kept bright ............ 206 Kettles, why do they become en- crusted with stony deposites ... 7(12 Kite, why does it rise in the air ... 840 Kite-string, why does it feel hot when running through the hand 841 Kite, why does running with it cause it to ascend ......... 8 12 Knowledge, why should we seek it 1 Knowledge, why does the posses- sion of it give us power ...... 2 Knowledge, what are the benefits of .. ............ 3 Latent heat, will the abstraction of it reduce the bulk of bodies ... 337 Latent heat, how do we know that it exists in air ......... 339 Laugh, why do we ......... 1026 Ligaments, what are they ...... 937 Ligaments, why are they wrapped around the joints ......... 938 Light, what is it ......... 451 Leaves, why are they green ... 1181 Leaves, why do some turn yellow 1186 Leaves, why do they fall off in the autumn ............ 1187 Leaves, how to make skeleton ... 1159 LESSON XLIV Leaves, why do they turn brown in autumn ............ 1183 Lees crossed, why do we see the elevated leg move at regular in- tervals :. .......... 918 Light, fit what velocity does it travel 453 Light, how long dues it take to travel from the sun to the earth 454 Light, what nre the minor sources of 45? Light, what is a nty of ...... 458 Light, what is a medium of ... 459 Light, what is a beam of ...... 460 Light, what is a pencil of ...... 461 Light, what is the radiant point ... 4fi'2 Light, what is the focus of ... 46.J Light, what is the constitution of a ray of ............... 464 Light, why are its rnys white ... 4(io Light, what are the estimated vib of 465 470 Light, what is the refraction of ... Light, is it refracted when it falls upon a surface in a straight line 473 Light, is the direction in wliich iis rays are best dependent on the d.-niities of the media ...... 474 Light, why does a epoon look bent when placed in a basin of water 477 Light, wliy do we see the rays of the sun burst through the clouds in different directions .. 474* xvm QUESTIONS FORMING A COMPLKTE INDKX. LESSON XLV. Light, why is the apparent depth of water always deceptive ... 479 Light, why are some substances opaque to it ... ... ... 511 Light, how do we know that bod- ies reflect it in every direction ... 517 Light, meditation on 517 Light and heat, what are the differ- ences between 540 Light and heat, are they combined in the sun's rays 541 Light and heat, how do we know that they are separate elements 542 Light and heat, in what respects are they similar 543 Light and heat, in what respects are they dissimilar ... ... ... 544 Light, what is polarized 549 Light, what is the velocity of arti- ficial 546 Light, at what rate does the light of the stars travel 547 Light, why does it tarnish silver ... 553 Light, why does it affect colours ... 554 Light, why can pictures be taken by the sun's rays 555 Light, when does it scorch plants 558 Lightning, what is the cause of ... 580 Lightning, why does it sometimes become zig-zag 586 Lightning, why is it sometimes forked 587 LESSON XLVI. ing, why is it sometimes like lurid sheet -... 58$ Lightning, when is the flash straight 587 Lightning, when does the flash ap- pear blue 591 Lightning, why is it sometimes red, at others blue, yellow, or white 592 Lightning, does it ever pass from the earth to the clouds 593 Lightning, does it pass from the clouds to the earth 594 Lightning, what is the force of ... 595 Lightning, why is it dangerous to stand near a tree during a storm 5S6 Lightning, why is it dangerous to sit near a fire during a storm ... 598 Lightning, why is it dangerous to be near water during a storm ... 599 Lightning, are iron houses danger- ous ... , 600 Lightning why does it seize upon bell wires, 2 4^0 41; QUESTIONS FORMING A COMPLETE INDEX. xxffl LESSON LXV. Snow, why is it warm, though white garments are cool 442 Snow, why is it always on the tops of high mountains ... ... 443 Snow-line, what is meant by the ... 445 Snow, what is red 446 So } a- water, why does it effer- vesce 802 Soils, why are clayey unfavourable to vfge-tation ... ... ... 1160 Soils, why are sandy unfavourable to vegetation 1162 Soils, why are chalk unfavourable to vegetation 1162 Soils, why are mixed favourable to vegetation 1163 Soils, why do farmers manure their land 1165 Soot, why should it be prevented from accumulating at the bot- tom and sides of sauce-pans ... 205 Soot, what is it 290 Sound, what is it 716 Sounds, what causes the air to pro- duce 717 Sounds, how do we know that they are produced by vibrations ... 718 Sounds, how do we know that without air there would be none 719 Sounds, how are the vibrations of sonorous bodies imparted to the air 720 LESSON LXVI. Sounds, how rapidly do the vibra- tions of travel 721 Sounds, do all sounds travel at the same rate t 722 Sounds, why are bells nnd glasses stopped from ringing by "touch- ing them with the finger 723 Sounds, why does a cracked bell give discordant 724 Sounds, why do we see the flash of a gun before we hear the report 725 Sound, why does the inarching of long ranks of soldiers appear to be irregular 726 Sound.*, what are the numbers of vibrations that produce various 727 Sounds, why does the length of a wire or string influence the sounds it produces 728 Sound, why does the tension of a wi re or string affect its vibrations 729 S.iund, why are some notes low iid solemn, and others high and quick 730 Sound, why can our voices be heard at a creator distance when we speak through tubes ... ... 731 Sound, is air a good conductor ... 732 S'lunds, why can we hear them at a greater distance on water than on land ... ... ., 733 LESSON LXV1I. Sound, why do sea-shells give a murmuring noise when held to the ear 734 Sound, why can people in the arc- tic regions converse when more than a mile apart 735 Sounds, why do savages lay their heads upon the earth to catch sounds 736 Sounds, why can church clocks be heard striking more plainly at some times than at others ... 737 Sound, why may the scratching of a pin at one end of a long pole be heard at the opposite ex- tiemly 738 Sound, why is the hearing of deaf persons assisted by ear-trumpets 739 Sounding-boards, why are they used to improve the hearing of congregations 740 Sounds, why, when we are walk- ing under arches or tunnels, do our voices appear louder ... 747 Spark, what causes it when a horse's shoe strikes against a stone 340 Specific gravity, what is it 789 Spiders, why have they the power of spinning webs ... ... ... 1082 Spider*,why may fine weather be ex- pect-d when they build their webs 1108 LESSON LXV1II. Spiders, wby may wet weather be expected when they hide ... 1109 Spiders, why may wet weather be expected when they break off their webs and remove them ... 1113 Spider, why, if the webs of the gossamer fly about in autumn, may east winds be expected ... 1124 Spiders, gossamer, why can they float through the air ... ... 1125 Spinal cord, what is the ... ,.. 952 Spinal cord, why is it placed in the back-bone ... 953 Spinal-cord, how do the branches pass out from it 954 Spontaneous combustion, what sub- stances are liable to it 317 Spontaneous combustion, has it ever occurred in living bodies ... 319 Spontaneous combustion, why doea it occur in the case of the drunk- ard 320 Spoon-bill, why has it a long ex- panded bill, lined with sharp, muscular points 1045 Spoon-bill, why has it long legs ... 1046 Squint, why do some people ... 967 Starch, what is it 1202 Star-lit nights, why are they usually colder than cloudy nights ... 350 Stars, why do they twinkle ... 484 QUESTIONS FORMING A COMPLKTK IN DUX. LESSON LXIX. Stars, why does their twinkling foretell had weather 485 Steam, why dons it issue from the spout of a kettle 750 Storms, what is the cause of ... 676 Storms, why do the mot vu.lent occur in and near the tropics ... 677 Straw, why is it frequently used for manure 1264 " Sucker, 1 ' why does it raise a stone 8fiO Sugar, what is it 1197 Sugar-cane, where is it cultivated... 1226 Sun, what is its distance from the earth 452 Sun, what is the ... 455 Sun, from what does its luminosity arise 456 Sun and moon, why do they appear smaller when near the meridian, than when near the horizon ... 525 Sun, why do we see it before sun- rise, and after sunset 482 Sun, what is the magnitude of the 767 Suppers, why do they cause dreams 1021 Swallows, why may wet weather be expected when they fly low 1104 Syringe, why does pressing in the handle force out a jet of water... 856 Syringe, why will not the water run out, unless the handle is pressed in 857 LESSON LXX. Syringe, why will the water leak out, but not run ... 858 Syringe, why cannot the handle be pressed in, if a finger is kept on the orifice 8-59 Tannin, what is it 1257 Taste, why do we 996 Taste, why are some substances sweet, others sour,