A dap tat ions 

 Adjustment 



SCIENTIFIC SIDE-LIGHTS 



14 



formed for some special purpose, if it now 

 serves for this end we are justified in saying 

 that it is specially adapted for it. On the 

 same principle, if a man were to make a ma- 

 chine for some special purpose, but were to 

 use old wheels, springs, and pulleys, only 

 slightly altered, the whole machine, with all 

 its parts, might be said to be specially con- 

 trived for its present purpose. Thus through- 

 out nature almost every part of each living 

 being has probably served, in a slightly 

 modified condition, for diverse purposes, and 

 has acted in the living machinery of many 

 ancient and distinct specific forms. DAR- 

 WIN Fertilization of Orchids, ch. 9, p. 283. 

 (A., 1898.) 



69. ADAPTIVENESS OF HUMAN OR- 

 GANISM Acquired Automatism Houdiris 

 Play with Balls. The extraordinary adapt- 

 iveness of the organism of man is shown in 

 his power of acquiring a vast number of 

 more special actions, which have no direct 

 relation to his bodily wants, but minister to 

 requirements of his own creation. These 

 often become, by a process of prolonged 

 " training," not less automatic than the act 

 of walking; as is shown by the fact that, 

 when once set going, they will continue in 

 regular sequence, not only without any 

 volitional exertion, but whilst the attention 

 is wholly directed elsewhere. . . . With 

 a view of cultivating the rapidity of visual 

 and tactile perception, and the precision of 

 respondent movements, which are necessary 

 for success in every kind of " prestidigita- 

 tion," Houdin early practised the art of 

 juggling with balls in the air; and having, 

 after a month's practice, become thorough 

 master of the art of keeping up four balls 

 at once, he placed a book before him, and, 

 while the balls were in the air, accustomed 

 himself to read without hesitation. CAR- 

 PENTER Mental Physiology, ch. 5, p. 217. 

 (A., 1900.) 



70. ADAPTIVENESS OF NATURE 



Wings for Other Use than Flight Penguin 

 " St earner "Ostrich. In these [Falk- 

 land] islands a great loggerheaded duck or 

 goose ... is very abundant. . . . 

 They are named, appropriately, steamers. 

 Their wings are too small and weak to allow 

 of flight, but by their aid, partly swimming 

 and partly flapping the surface of the water, 

 they move very quickly. These clumsy, log- 

 gerheaded ducks make such a noise and 

 splashing that the effect is exceedingly cu- 

 rious. Thus we find in South America three 

 birds which use their wings for other pur- 

 poses besides flight : the penguin as fins, the 

 steamer as paddles, and the ostrich as sails ; 

 and the apteryx of New Zealand, as well as 

 its gigantic extinct prototype the deinornis, 

 possess only rudimentary representatives 

 of wings. DARWIN Naturalist's Voyage 

 Around the World, ch. 9, p. 200. (A., 1898.) 



71. ADJUSTMENT OF AERIAL TEM- 

 PERATURE -Dead-line of Cold Just Over- 



hangs Zone of Life Earth's Heat Not 

 Greatly Changed through Geologic Ages. 

 It is not easy to appreciate the delicacy of 

 adjustment which is required to establish 

 this temperature demanded by organic life, 

 and to maintain it through the geological 

 ages. Even in the permanent heat of the 

 equator the zone of life-killing cold lies but 

 four miles above the surface of the sea. As 

 soon as night comes on, this dead-line begins 

 to descend toward the surface; by morning 

 it may have fallen to within three miles of 

 the sea-level. A week of continued night 

 would lock the tropics in a deadly frost and 

 make an end of its land-life. SHALER As- 

 pects of the Earth, p. 201. (S., 1900.) 



72. ADJUSTMENT OF CHEMICAL 

 AFFINITIES IN THE BODY Life Supreme. 

 There is indeed an adjustment a close 

 and intricate adjustment between the 

 chemical affinities of these elements as they 

 are combined in the living body; but it is 

 an adjustment of them under the control- 

 ling energy of a power which cannot be iden- 

 tified with any other, and which always 

 presents phenomena peculiar to itself. Un- 

 der that power we see that the laws and 

 forces of chemical affinity, as exhibited 

 apart from life, are held, as it were, to serv- 

 ice compelled, indeed, to minister, but not 

 allowed to rule. Through an infinite va- 

 riety of organisms this mysterious subor- 

 dination is maintained, ministering through 

 an ascending series to higher and higher 

 grades of sensation, perception, conscious- 

 ness, and thought. ARGYLL Unity of Na- 

 ture, ch. 2, p. 34. (Burt.) 



73. ADJUSTMENT OF MENTAL 

 FORCES Conduct Determined by Combina- 

 tion of Motives. It is true, indeed, that 

 there are in the mind of man, as there are 

 in nature, certain forces originally im- 

 planted which are unchangeable in this 

 sense, that they have an invariable tendency 

 to determine conduct in a particular direc- 

 tion. But as in nature we have a power of 

 commanding her elementary forces by the 

 methods of adjustment, so in the realm of 

 mind we can operate on the same principle, 

 by setting one motive to counteract an- 

 other: and by combination among many 

 motives we can influence in a degree, and to 

 an extent as yet unknown, the conduct and 

 the condition of mankind. ARGYLL Reign 

 of Law, ch. 7, p. 219. (Burt.) 



74. ADJUSTMENT OF ORGANISM TO 



ENVIRONMENT Wing-feathers and Auricu- 

 lars in Birds Internal vs. External Corre- 

 lation. There are two correlations of 

 growth in respect to feathers which are con- 

 stant. In all cases (excepting, of course, 

 the wingless birds) the feathers which 

 grow from the forearm and finger-bones, 

 constituting the wings, are comparatively 

 long, strong, tapering, elastic, and with thin 

 lateral filaments, which filaments are 

 closely hooked together by means of minute 



