Development 

 Dew 



SCIENTIFIC SIDE-LIGHTS 



166 



Analogies the most interesting have brought 

 the distant orbs of heaven into close rela- 

 tionship with our own earth or with the cen- 

 tral luminary of the planetary scheme. And 

 a lesson has been taught us which bears even 

 more significantly on our views respecting 

 the existence of other worlds : we have 

 learned to recognize within the solar system, 

 and within the wondrous galaxy of which 

 our sun is a constituent orb, a variety of 

 structure and a complexity of detail of 

 which but a few years ago astronomers had 

 formed but the^most inadequate conceptions. 

 PROCTOR Other Worlds than Ours, int., p. 

 19. (Burt.) 



811. 



Astronomy Histor- 



ically the First of the Sciences Next, Me- 

 chanics. For a time and that historically 

 a long one he [man] was limited to mere 

 observation, accepting what Nature offered, 

 and confining intellectual action to it alone. 

 The apparent motions of sun and stars first 

 drew towards them the questionings of the 

 intellect, and accordingly astronomy was the 

 first science developed. Slowly, and with 

 difficulty, the notion of natural forces took 

 root in the human mind. Slowly, and with 

 difficulty, the science of mechanics had to 

 grow out of this notion; and slowly at last 

 came the full application of mechanical 

 principles to the motions of the heavenly 

 bodies. We trace the progress of astron- 

 omy through Hipparchus and Ptolemy; and, 

 after a long halt, through Copernicus, Gali- 

 leo, Tycho Brahe, and Kepler; while from 

 the high table-land of thought raised by 

 these men Newton shoots upward like a 

 peak, overlooking all others from his domi- 

 nant elevation. TYNDALL Lectures on 

 Light, lect. 1, p. 4. (A., 1898.) 



812. DEVELOPMENT OF SENSES AS 

 WELL AS MUSCLES BY PRACTISE 



Possible Discrimination of Minute Differ- 

 ences of Sensation. That " practise makes 

 perfect " is notorious in the field of motor 

 accomplishments. But motor accomplish- 

 ments depend in part on sensory discrimina- 

 tion. Billiard-playing, rifle- shooting, tight- 

 rope-dancing, demand the most delicate 

 appreciation of minute disparities of sensa- 

 tion, as well as the power to make accu- 

 rately graduated muscular response thereto. 

 In the purely sensorial field we have the 

 well-known virtuosity displayed by the pro- 

 fessional buyers and testers of various kinds 

 of goods. One man will distinguish by taste 

 between the upper and the lower half of a 

 bottle of old Madeira. Another will recog- 

 nize, by feeling the flour in a barrel, whether 

 the wheat was grown in Iowa or Tennessee. 

 The blind deaf-mute, Laura Bridgman, had 

 so improved her touch as to recognize, after 

 a year's interval, the hand of a person who 

 once had shaken hers ; and her sister in mis- 

 fortune, Julia Brace, is said to have been 

 employed in the Hartford Asylum to sort 

 the linen of its multitudinous inmates, after 



it came from the wash, by her wonderfully 

 educated sense of smell. JAMES Psychology, 

 vol. i, ch. 13, p. 509. (H. H. & Co., 1899.) 



813. DEVELOPMENT, ORDERLY, OF 



UNIVERSE Astronomy, Geology, Zoology Al- 

 lied One Grand Movement Pervading All 

 Sciences. It was not until the nineteenth 

 century that the microscope . . . was 

 perfected as an instrument, and accom- 

 plished for zoology its final and most im- 

 portant service. . . . 



On the other hand, the astronomical the- 

 ories of development of the solar system 

 from a gaseous condition to its present form, 

 put forward by Kant and by Laplace, had 

 impressed men's minds with the conception 

 of a general movement of spontaneous prog- 

 ress or development in all Nature ; and, tho 

 such ideas were not new, but are to be found 

 in some of the ancient Greek philosophers, 

 yet now for the first time they could be con- 

 sidered with a sufficient knowledge and cer- 

 tainty as to the facts, due to the careful ob- 

 servation of the two preceding centuries. 

 The science of geology came into existence, 

 and the whole panorama of successive stages 

 of the earth's history, each with its distinct 

 population of strange animals and plants, 

 unlike those of the present day and simpler 

 in proportion as they recede into the past, 

 was revealed by Cuvier, Agassiz, and others. 

 The history of the crust of the earth was ex- 

 plained by Lyell as due to a process of slow 

 development, in order to effect which he 

 called in no cataclysmal agencies, no mys- 

 terious forces differing from those operating 

 at the present day. Thus he carried on the 

 narrative of orderly development from the 

 point at which it was left by Kant and La- 

 place explaining by reference to the ascer- 

 tained laws of physics and chemistry the 

 configuration of the earth, its mountains 

 and seas, its igneous and its stratified rocks, 

 just as the astronomers had explained by 

 those same laws the evolution of the sun 

 and planets from diffused gaseous matter of 

 high temperature. 



The suggestion that living things must 

 also be included in this great development 

 was obvious. LANKESTER History and 

 Scope of Zoology, p. 7. (Hum., 1893.) 



814. DEVELOPMENT, PSYCHICAL, 

 ARRESTS PHYSICAL Future Progress 

 within the Mind, Not the Body. Alfred 

 Russel Wallace, the illustrious codiscoverer 

 of natural selection, saw that along with the 

 general development of mammalian intelli- 

 gence a point must have been reached in the 

 history of one of the primates when vari- 

 ations of intelligence were more profitable 

 to him than variations in body. From that 

 time forth that primate's intelligence went 

 on by slow increments acquiring new capac- 

 ity, while his body changed but little. When 

 once he could strike fire, and chip a flint, 

 and use a club, and strip off the bear's hide 

 to cover himself, there was clearly no further 

 use in thickening his own hide, or lengthen- 



