276 THE EVOLUTION OF LIFE 
I am disposed to think that the A solution bears 
high temperatures worse than the AA solution. I 
have heated very few of the former to 130° C.,, 
but many specimens of the latter, and in none of 
them have I found a great crowd of large inorganic 
particles such as are shown in Fig. 37. In some of 
the solutions, indeed, the flakes of silica have scarcely 
shown any such particles—many of them in these 
cases presenting only a uniformly fine granular tex- 
ture, such as may be dimly seen in Figs. 25 and 
28. 
It seems clear, therefore, that just as solutions 
of organic matter are degraded by high tempera- 
tures, so are saline solutions liable to be altered 
in very different ways; till at last there comes 
a limit to the possibility of obtaining results which 
appear freely enough at lower temperatures. Certain 
it is, that in none of these saline solutions containing 
silica have I, as yet, been able to find living organ- 
isms in tubes that had been heated to temperatures 
above 130 C. It may be, of course, that longer 
periods of exposure to light might lead to different 
results. 
I have, however, had some remarkable results 
with sea-water heated to 135°’ C., and even to 
‘““A liquid does not possess constant and unchangeable properties at 
the same temperature and pressure. All liquids in nature form allo- 
tropic modifications, such as have been known in the case of sulphur, 
phosphorus, iron, etc. Such an allotropic modification is formed in 
larger quantity, the more quickly the fluid ts cooled.” Some of my 
tubes after heating, when taken from the bath, have been left to cool 
slowly, though others have been purposely cooled more quickly, before 
cleaning and labelling them. No record, however, was kept of such 
slight differences in treatment. 
