rh 



88 



THE BEGINNINGS OF LIFE. 



er 



leading part in organic actions. According to Muld 

 the formula of albumen is lo (C40 Hg^ N^ O^^) 4-Sp' 

 That is to say, with the sulphur and phosphorus there 

 are united ten equivalents of a compound atom 



■con* 



taining forty atoms of carbon, thirty-one of hydrogen 

 five of nitrogen, and twelve of oxygen: the atom 

 being thus made up of nearly nine hundred ultimate 

 atoms,' 



i 



■ 



These complex nitrogenous compounds, to the pro- 

 perties of which we have just been alluding^ belong to 

 the class of bodies named colloids by Professor Graham. 

 They all have an extremely low diffusive power when 

 in solution^ and on this account they have been sepa- 

 rated from the crystalloids^ or kinds of matter which 

 tend to crystallize, and also undergo diffusion much 

 more rapidly. Gelatine may be taken as the type of 



'/ 



A most radical dis 



tinction is presumed to exist between crystalloids and 

 colloids, in regard to their intimate molecular con- 

 stitution. Professor Graham says ^ : — ^ Every physical 

 and chemical property is characteristically modified in 

 each class. They appear like different worlds of matter^ 

 and give occasion to a corresponding division of chemical 

 science. The distinction between these kinds of matter 

 is that subsisting between the material of a mineral, 

 and the material of an organized mass/ Referring to 

 the colloidal class of substances. Professor Graham also 



1 « 



Phil. Trans.' 1861, p. 220. 



> 



the bodies 



their hy^irates. 



are 



(listing 



are 



appear 



held in s 

 singularly 



es, and in all 1 

 tlie other banc 

 iri the chemica 

 ie required in si 



processes 



imal body are fc 



( M so all-import; 

 J stnictural and fi 

 't is most dcsirab 



ttrning their 



■f' Hen the 

 '"§ bodies. 



pro] 



y 



'icate i 



It 



tendenc 

 "^Pressio 



^^*. of the 



e 



actio 



n 



mor 



n 



and,- 



1 



est 



J^ind 



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