217 



SCIENTIFIC SIDE-LIGHTS 



Error 

 Errors 



more certain facts have been deemed su- 

 perior in utility to those which bestow a 

 higher cultivation on the higher faculties of 

 the mind. HAMILTON Metaphysics, lect. 1, 

 p. 3. (G. & L., 1859.) 



1O58. ERRORS OF SCIENTISTS A 



Classification that Would Include the Hog 

 among Ruminants. Cuvier taught that 

 there was always a coordination between the 

 various systems of the animal frame and 

 that, from the remains or impress of one 

 part, the approximate structure of the other 

 parts could be inferred. He even pushed 

 this doctrine to such an extreme that he 

 overlooked some obvious counter-facts. One 

 such case is so remarkable, because it origi- 

 nated with Cuvier and was indorsed by Hux- 

 ley, that it is worthy of mention here, and 

 Huxley's introduction to it and translation 

 of it may be given [from his " Introduction 

 to the Classification of Animals," 1869, 

 ch. 1]: 



"... I doubt if any one would have 

 divined, if untaught by observation, that all 

 ruminants have the foot cleft, and that they 

 alone have it; . . . so that now, whoso 

 sees merely the print of a cleft foot may 

 conclude that the animal which left this im- 

 pression ruminated, and this conclusion is 

 as certain as any other in physics or 

 morals." 



Some men, with much less knowledge than 

 either Cuvier or Huxley, may at once re- 

 call living exceptions to the positive state- 

 ments as to the coordination of the " foot 

 cleft " with the other characters specified. 

 One of the most common of domesticated 

 animals the hog would come up before the 

 , " mind's eye," if not the actual eye at the 

 moment, to refute any such correlation as 

 was claimed. Nevertheless, notwithstanding 

 the fierce controversial literature centered 

 on Huxley, no allusion appears to have been 

 made to the lapsus. Yet every one will ad- 

 mit that the hog has the "foot cleft" as 

 much as any ruminant, but the " form of the 

 teeth " and the form of some vertebrae are 

 quite different from those of the ruminants, 

 and of course the multiple stomach and 

 adaptation for rumination do not exist in 

 the hog. That any one mammalogist should 

 make such a slip is not very surprising, but 

 that a second equally learned should follow 

 in his steps is a singular psychological curi- 

 osity. GILL Edward Drinker Cope, Natural- 

 ist, in Proc. Amer. Assoc. for the Advance- 

 ment of Science, vol. xlvi, p. 17. (1897). 



1Q59. , All Nebula Once 



Supposed Resolvable " Island Universes " 

 Correction of Error "by Spectroscope. 

 Altho Lord Rosse himself rejected the in- 

 ference that because many nebula? had been 

 resolved, all are resolvable, very few imi- 

 tated his truly scientific caution; and the 

 results of Bond's investigations with the 

 Harvard College refractor quickened and 

 strengthened the current of prevalent opin- 

 ion. It is now certain that the evidence fur- 



nished on both sides of the Atlantic as to the 

 stellar composition of some conspicuous ob- 

 jects of this class, notably the Orion and 

 " Dumb-bell " nebulae, was delusive ; but the 

 spectroscope alone was capable of meeting 

 it with a categorical denial. Meanwhile 

 there seemed good ground for the persua- 

 sion, which now, for the last time, gained 

 the upper hand, that nebulae are, without ex- 

 ception, true " island universes," or assem- 

 blages of distant suns. CLERKE History of 

 Astronomy, pt. i, ch. 6, p. 147. (BL, 1893.) 



1060. 



Astronomers Once 



Denied Satellites to Mars Their Discovery 

 by Persistent Search. We know now that 

 this world [Mars] travels round the sun ac- 

 companied by two satellites. Their discov- 

 ery was made in 1877, by Professor Asaph 

 Hall, at the Observatory of Washington, by 

 the aid of the most powerful telescope which 

 existed at that time. It was not due to 

 chance, like that of a great number of small 

 planets and comets, but it was the result of 

 a systematic search. Most astronomers were 

 accustomed, like ordinary mortals, to read 

 in the standard books the usual phrase, 

 " Mars has no satellites " ; however, some, 

 doubting this assertion, continued to seek to 

 surprise the secrets of Nature, which always 

 keeps more than it allows us to grasp. They 

 had already searched the neighborhood of 

 Mars; but the instruments they used were 

 much inferior to the equatorial of Washing- 

 ton, of which the object-glass measures no 

 less than 66 centimeters (26 inches) in 

 diameter, of which the focal length is 10 

 meters (32.8 feet), of which the optical 

 power permits a magnification of 1,300 

 times, and which is moved by a mechanism 

 of the greatest precision. By the aid of this 

 excellent apparatus the eminent American 

 astronomer undertook the attentive exami- 

 nation of the neighborhood of Mars from the 

 beginning of the month of August, 1877, in 

 order to observe assiduously this neighbor- 

 ing planet during the favorable epoch of its 

 greatest proximity to the earth. After long 

 evenings of barren expectation, he was about 

 to abandon the search, when, encouraged by 

 the entreaties of his wife, he persisted, and 

 discovered a satellite during the night of the 

 llth, then a second on the night of the 17th. 

 FLAMMARION Popular Astronomy, bk. iv, 

 ch. 4, p. 393. (A.) 



1O61. 



Comets Styled "Vis- 



ible Nothings " Solidity of Meteorites 

 Nuclei of Comets. Ought we, then, to laugh 

 at them [comets], and, with Sir John Her- 

 schel and Babinet, treat them as visible 

 nothings? No; that would be the other ex- 

 treme. Several comets seem to have solid 

 nuclei. Solid bodies have already encoun- 

 tered the earth, have fallen on its surface, 

 have killed men and set fire to houses. Most 

 of the meteorites collected are, it is true, but 

 small fragments of some few pounds in 

 weight ; but some have been met with which 

 weigh several thousands of pounds. This is 



