THE BREATH OF LIFE 



chemical change in the sea-water. The eyes of cer- 

 tain fish embryos may be fused into a single cyclo- 

 pean eye by adding magnesium chloride to the 

 water in which they live. Loeb says, "It is a priori 

 obvious that an unlimited number of pathological 

 variations might be produced by a variation in the 

 concentration and constitution of the sea water, and 

 experience confirms this statement." It has been 

 found that when frog's eggs are turned upside down 

 and compressed between two glass plates for a num- 

 ber of hours, some of the eggs give rise to twins. 

 Professor Morgan found that if he destroyed half 

 of a frog's egg after the first segmentation, the re- 

 maining half gave rise to half an embryo, but that 

 if he put the half -egg upside down, and compressed 

 it between two glass plates, he got a perfect embryo 

 frog of half the normal size. Such things show how 

 plastic and adaptive life is. Dr. Carrel's experi- 

 ments with living animal tissue immersed in a 

 proper mother-liquid illustrate how the vital proc- 

 ess cell-multiplication may be induced to go 

 on and on, blindly, aimlessly, for an almost indefi- 

 nite time. The cells multiply, but they do not organ- 

 ize themselves into a constructive community and 

 build an organ or any purposeful part. They may 

 be likened to a lot of blind masons piling up brick 

 and mortar without any architect to direct their 

 work or furnish them a plan. A living body of the 

 higher type is not merely an association of cells; it is 

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