188 The Mechanistic Conception of Life 



IX 



The objection might be raised that the beneficial action of 

 the three salts could only be proved on marine animals or on 

 tissues of higher animals, which are said to be "adapted" to a 

 mixture of NaCl, KCl, and CaClj in definite proportions. 

 Experiments on fresh-water organisms, for which "adaptation" 

 to a mixture of NaCl, KCl, and CaCl^ in these definite propor- 

 tions cannot be claimed, show that this objection is not valid. 

 Ostwald worked with fresh-water crustaceans which he put into 

 mixtures of various salts. It was found that these animals 

 live longer in a mixture of NaCl + KCl H-CaClj than in a solu- 

 tion of NaCl, or NaCl+KCl, or NaCl+CaCl, of the same 

 osmotic pressure. 



Osterhout was able to show that the spores of a certain 

 variety of Vaucheria die in a pure 3/32 m solution of NaCl ia 

 10 to 20 muiutes, while they live in 100 c.c. 3/32 m NaCl-f-1 c.c. 

 3/32 CaClj 2 to 4 weeks, and in 100 c.c. 3/32 m NaCl+1 c.c. 

 3/32 m CaClj+2.2 c.c. 3/32 m KCl 6 to 8 weeks. The reac- 

 tion of the solution was strictly neutral and the NaCl the purest 

 obtainable. The results remained the same after the NaCl 

 had been recrystalUzed six times. Experiments with Spirogyra 

 gave a similar result. The solutions were all 3/32 m. In 

 NaCl the Spirogyra died in 18 hours; in NaCl+KCl in two 

 days; in NaCH-KCl-fCaCl^ they lived 65 days. Osterhout 

 caused wheat grains to develop La such solutions and measured 

 the total length of the roots formed. 



Total Length of 

 Nature ol the Solution Roots after 40 Days 



H3O 740 mm. 



100 c.c. 3/25 NaCl 59 mm. 



100 c.c. 3/25 NaCH-2.0 3/25 CaCl. 254 mm. 



100 c.c. 3/25 NaCl-l-2.0 3/25 CaCL+2.2 3/25 m KCl 324 mm. 



These cases, to which many other similar observations might 

 be added, prove that the life-preserviag effect of the combina- 

 tion of NaCl -|- KCl +CaCl2 in definite proportions is not due 



