184 WHAT IS LIFE ? 



In these deposits there are layers of limestone of such 

 an extraordinary structure, as to make many eminent 

 geologists believe that they were formed by a simple 

 organism, consisting of what is termed protoplasm, pro- 

 bably masses of simple living molecules, each having 

 an independent motion, but these molecules in living 

 protoplasm are so minute as to be incapable of being 

 seen by the very highest magnifying power. The mass 

 of these objects secreted the carbonate of lime from 

 the water and thus formed its living-place, protruding 

 the living matter through minute holes in the shell 

 and thus obtaining its food. Such is one explanation 

 of the ancient mass called the Eozoon Canadeitse. It 

 is estimated that one band of this formation of lime- 

 stone in the Ottawa district reaches a thickness of 

 nearly thirty feet. This is believed by many able 

 geologists to be the first evidence of life on the surface 

 of the earth. Whether this is so or not, " it may be 

 admitted that no structure precisely similar to that 

 of some of the specimens of Eozoon has yet been 

 discovered in the mineral kingdom." 1 



It matters little if this be regarded as indications 

 of the first life, for there is sufficient evidence that life 

 existed in the pre-Cambrian strata. 2 This life was 

 probably of the lowest type. " The mere thickness 

 and variety of the pre-Cambrian formations, together 

 with their unconformabilities and other structural fea- 

 tures, suffice to prove that they represent an enormous 

 chronological interval. In North America, where, 

 so far as at present known, they are most extensively 



1 Idem, p. 695. Idem, p. 694. 



