THE NEW EARTH 



themselves in two, each divided half in turn 

 subdividing itself; and so they go on and on 

 increasing at a marvelous progression. They 

 are so infinitely small that it is impossible to 

 conceive the rapidity of their increase when 

 they are in the act of multiplying themselves. 

 One of them, according to a bacteriologist who 

 had studied it closely, would, if left to itself, 

 produce seventeen million descendants in 

 twenty-four hours. Another scientist calcu- 

 lates that another particularly rapid multiplier 

 could produce, if it had plenty of food to eat 

 in the meantime, four thousand, seven hundred 

 and seventy-two billion progeny in a single 

 day. In three days' time the reproduction, if 

 unobstructed, would be so great that the mass 

 would weigh seven thousand, five hundred 

 tons. 



Some of the bacteria are round, some ellip- 

 tical, some thread-like or spiral, some branch- 

 ing, some rod-like. Each one has a central life 

 point, which the word cell describes as well as 

 any other. When they divide themselves, each 

 half is given a complete life of its own with all 

 the powers and functions of the old. They 

 differ from the plants which we see growing 



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