Life 



SCIENTIFIC SIDE-LIGHTS 



1893 LIFE IN INFUSIONS Errors 



of Experiment Lifelessness Presumes Cor- 

 rect Manipulation. As regards workman- 

 ship, moreover, he [the investigator] will 

 not fail to bear in mind that fruitfulness 

 may be due to errors of manipulation, while 

 barrenness involves the presumption of cor- 

 rect experiment. It is only the careful 

 worker that can secure the latter, while it is 

 open to every novice to obtain the former. 

 Barrenness is the result at which the con- 

 scientious experimenter, whatever his the- 

 oretic convictions may be, ought to aim, 

 omitting no pains to secure it, and resorting 

 only when there is no escape from it to the 

 conclusion that the life observed comes from 

 no source which correct experiment could 

 neutralize or avoid. TYNDALL Fragments of 

 Science, vol. ii, ch. 13, p. 318. (A., 1900.) 



1894. LIFE IN OCEAN DEPTHS 



A Few Fossil Forms Still Living Most 

 Forms Modern Modified. Besides proving 

 the existence of a fauna in the sea at all 

 depths and in all regions, the expedition [of 

 the " Challenger," 1873] further proved that 

 the abysmal fauna, taken as a whole, does 

 not possess characters similar to those of 

 the fauna of any of the Secondary or even 

 Tertiary rocks. A few forms, it is true, 

 known to us up to that time only as fossils, 

 were found to be still living in the great 

 depths, but a large majority of the animals 

 of these regions were found to be new and 

 specially modified forms of the families and 

 genera inhabiting shallow waters of modern 

 times. No trilobites, no blastoids, no cys- 

 toids, no new ganoids, and scarcely any 

 deep-sea elasmobranchs were brought to 

 light, but the fauna was found to consist 

 mainly of teleosteans, Crustacea, coelentera, 

 and other creatures unlike anything known 

 to have existed in Paleozoic times, specially 

 modified in structure for their life in the 

 great depths of the ocean. HICKSON Fauna 

 of the Deep Sea, ch. 1, p. 14. (A., 1894.) 



1895. 



How the Mighty 



Pressure Is Borne Glass Crushed to Pow- 

 der. In regard to the animal life of the 

 deep sea, the " Challenger " researches do not 

 seem likely to yield any new general result 

 of striking interest. Our previous work had 

 shown that a depth of three miles, a pres- 

 sure of three tons on the square inch, an 

 entire absence of sunlight, and a tempera- 

 ture below 32 might be sustained by a 

 considerable number and variety of animal 

 types, and this conclusion has been fully 

 confirmed and widely extended. Many speci- 

 mens have been brought up alive from depths 

 exceeding four miles, at which the pressure 

 was four tons on the square inch, consider- 

 ably exceeding that exerted by the hydraulic 

 presses used for packing Manchester goods. 

 Even the " protected " thermometers special- 

 ly constructed for deep-sea sounding were 

 frequently crushed; and a sealed glass tube 

 containing air, having been lowered (within 

 a copper case) to a deptfi of 2,000 fathoms, 



was reduced to a fine powder almost like 

 snow by what Sir Wyville Thomson inge- 

 niously characterized as an implosion, the 

 pressure having apparently been resisted un- 

 til it could no longer be borne, and the 

 whole having been then disintegrated at the 

 same moment. The rationale of the resist- 

 ance afforded by soft-bodied animals to a 

 pressure which thus affects hard glass is 

 simply that they contain no air, but consist 

 of solids and liquids only; and that since 

 their constituent parts are not subject to 

 more than a very trifling change of bulk, 

 while the equality of the pressure in every 

 direction will prevent any change in their 

 form, there is really nothing to interfere 

 with the ordinary performance of their vital 

 functions. CARPENTER Nature and Man, 

 lect. 11, p. 344. (A., 1889.) 



1896. LIFE IN UNEXPECTED 



PLACES Worms that Live in Brine Every 

 Part of the World Habitable Why Not Life 

 in Other Worlds? The mud in many places 

 [about the salt lakes] was thrown up by 

 numbers of some kind of worm, or annel- 

 idous animal. How surprising it is that 

 any creatures should be able to exist in 

 brine, and that they should be crawling 

 among crystals of sulfate of soda and 

 lime! And what becomes of these worms 

 when during the long summer the surface 

 is hardened into a solid layer of salt? Fla- 

 mingoes in considerable numbers inhabit this 

 lake and breed here; throughout Patagonia, 

 in northern Chile, and at the Galapagos Is- 

 lands I met with these birds wherever there 

 were lakes of brine. 1 saw them here wa- 

 ding about in search of food probably for 

 the worms which burrow in the mud; and 

 these latter probably feed on infusoria or 

 confervse. Thus we have a little living world 

 within itself, adapted to these inland lakes 

 of brine. . . . 



Well may we affirm that every part of the 

 world is habitable ! Whether lakes of brine, 

 or those subterranean ones hidden beneath 

 volcanic mountains warm mineral springs 

 the wide expanse and depths of the ocean 

 the upper regions of the atmosphere, and 

 even the surface of perpetual snow all sup- 

 port organic beings. DARWIN Naturalist's 

 Voyage around the World, ch. 4, p. 66. (A., 

 1898.) 



1897. LIFE, ITS TRANSFORMING 

 POWER Exchange of Functions among Vital 

 Organs. The roots and leaves of plants are 

 widely differentiated in their functions: by 

 the roots, water and mineral substances are 

 absorbed, while the leaves take in and de- 

 compose carbonic acid. Nevertheless, some 

 leaves can absorb water, and in what are 

 popularly called " air-plants " the absorp- 

 tion of water is mainly carried on by them 

 and by the stems. Conversely, the under- 

 ground parts can partially assume the func- 

 tions of leaves. The exposed tuber of a po- 

 tato develops chlorophyl on its surface, and 

 in other cases, as in that of the turnip, 

 roots, properly so called, do the like. In 



