Meteorites 

 Microscope 



SCIENTIFIC SIDE-LIGHTS 



442 



guished in the air immediately after its ig- 

 nition, nor yet an inflammatory combustion 

 of the air, which is dissolved in large quan- 

 tities in the upper regions of space, but 

 these meteors are rather a fall of celestial 

 bodies, which, in consequence of a certain 

 intermission in the rotatory force, and by 

 the impulse of some irregular movement, 

 have been hurled down not only to the in- 

 habited portions of the earth, but also be- 

 yond it into the great ocean, where we can- 

 not find them." Diogenes of Apollonia 

 expresses himself still more explicitly. Ac- 

 cording to his views, " Stars that are invis- 

 ible, and, consequently, have no name, move 

 in space together with those that are visible. 

 These invisible stars frequently fall to the 

 earth and are extinguished, as the stony 

 star which fell burning at Egos Potamos." 

 HUMBOLDT Cosmos, vol. i, p. 133. (H., 

 1897.) 



2162. METEORS, FALL OF, UPON 

 THE SUN Cannot Supply His Heat.^ow 

 we may assume with great probability that 

 very many more meteors fall upon the sun 

 than upon the earth, and with greater 

 velocity, too, and therefore give more heat. 

 Yet the hypothesis that the entire amount 

 of the sun's heat which is continually lost 

 by radiation is made up by the fall of 

 meteors, a hypothesis which was propounded 

 by Mayer, and has been favorably adopted 

 by several other physicists, is open, accord- 

 ing to Sir W. Thomson's investigations, to 

 objection; for, assuming it to hold, the 

 mass of the sun should increase so rapidly 

 that the consequences would have shown 

 themselves in the accelerated motion of the 

 planets. The entire loss of heat from the 

 sun cannot at all events be produced in this 

 way ; at the most a portion, which, however, 

 may not be inconsiderable. HELMHOLTZ 

 Popular Lectures, lect. 4, p. 180. (L. G. & 

 Co., 1898.) 



2163. METEORS IN TRACK OF LOST 

 COMET To be lost is interesting, espe- 

 cially for a comet; but this, doubtless, was 

 not enough, for it reserved for us a still 

 more complete surprise. Its orbit intersects 

 the terrestrial orbit at a point which the 

 earth passes on November 27, 1872. Well, 

 nothing more was thought about it; it was 

 given up as hopeless, when, on the evening 

 of November 27, 1872, there fell from the 

 sky a veritable rain of shooting stars. The 

 expression is not exaggerated; they fell in 

 great flakes; lines of fire glided almost 

 vertically in swarms and showers, here with 

 dazzling globes of light, there with silent 

 explosions recalling to mind those of rock- 

 ets ; and this rain lasted from seven o'clock 

 in the evening till one o'clock next morning, 

 the maximum being attained about nine 

 o'clock. At the observatory of the Roman 

 College 13,892 were counted; at Montcali- 

 eri, 33,400; in England a single observer 

 counted 10,579, etc. The total number has 

 been estimated at a hundred and sixty thou- 

 sand. They all came from the same point 



of the sky, situated near the beautiful star 

 Gamma of Andromeda. . . . What was 

 this shower of stars? Evidently and this 

 is not doubtful the encounter with the 

 earth of myriads of corpuscles moving in 

 space along the orbit of Biela's comet. The 

 comet itself, if it still existed, would have 

 passed twelve weeks before. It was not, 

 then, to speak correctly, the comet itself 

 which we encountered, but perhaps a frac- 

 tion of its decomposed parts, which, since 

 the breaking-up of the comet in 1846, would 

 be dispersed along its orbit behind the head 

 of the comet. FLAMMARION Popular As- 

 tronomy, bk. v, ch. 2, p. 500. (A.) 



2164. METHOD, IMPORTANCE OF, 

 IN PREPARATORY TRAINING It does 

 not matter so much what a scholar learns 

 in the secondary school as how he learns. 

 In other words, the method according to 

 which the pupil is instructed and learns to 

 think is decisive, as regards his preparatory 

 training, of his capacity for future study. 

 ERDMANN Ueber des Studium der Chemie, p. 

 11. (Translated for Scientific Side-Lights.) 



2165. METHOD OF ATTAINING SCI- 

 ENTIFIC CONCLUSION Growth of Coral 

 Only at Small Depths. The circumstance of 

 a gradual change from a field of clean coral 

 to a smooth sandy bottom is far more im- 

 portant in indicating the depth at which the 

 larger kinds of coral flourish than almost 

 any number of separate observations on the 

 depth at which certain species have been 

 dredged up. For we can understand the 

 gradation only as a prolonged struggle 

 against unfavorable conditions. If a person 

 were to find the soil clothed with turf on the 

 banks of a stream of water, but on going to 

 some distance on one side of it he observed 

 the blades of grass growing thinner and 

 thinner with intervening patches of sand, 

 until he entered a desert of sand, he would 

 safely conclude, especially if changes of the 

 same kind were noticed in other places, that 

 the presence of the water was absolutely 

 necessary to the formation of a thick bed of 

 turf: so may we conclude, with the same 

 feeling of certainty, that thick beds of coral 

 are formed only at small depths beneath the 

 surface of the sea. DARWIN Coral Reefs, 

 ch. 4, p. 111. (A., 1900.) 



2166. METHOD OF SCIENCE VS. 

 THAT OF RELIGION In matters of sci- 

 ence, light descends from the head to the 

 heart; but in religion light ascends from 

 the heart to the head. Only so far as we 

 live in God can we understand him. 

 THOUICK Inscription in a Book. (Trans- 

 lated for Scientific Side-Lights.) 



2167. METHOD, THE VALUE OF 



Science Works to Definite Results. Two 

 things are of particular remark in the dis- 

 coveries in the Roman catacombs during the 

 last thirty-eight years. First, they are the 

 works of a single man; no one, this may be 

 asserted, shares the fame of Giovanni 



