HEAT UPON LIVING MATTER. 163 
experiments on the Origin of Life question we wish 
to know the effects of great heat upon organisms 
accustomed to ordinary atmospheric and aquatic 
temperatures. On the other hand, it should be 
pointed out that organisms have been found living 
in hot springs at temperatures very considerably 
above those I have just been quoting ; although the 
very highest of the temperatures, under the influence 
of which living things have been reported as existing 
in thermal springs, is still a few degrees below the 
boiling point of water. The various observations 
made upon this subject have been collected and 
criticised with much care by Professor Jeffries 
Wyman,* to whose paper I would refer the reader. 
The most remarkable instances—that is, the highest 
temperatures cited which are at all trustworthy—in 
which Conferve, or allied organisms, have been met 
with, are thus summarized by Professor. Wyman. 
“The statements we have quoted,” he says, “ give 
satisfactory proof that different kinds of plants may 
live in water of various temperatures, as high as 
168° F. as observed by Dr. Hooker in Sorujkund ; 
174° as observed by Captain Strachey in Thibet ; 
185° as observed by Humboldt in La Trinchéra ; 
199°:as. observed by Dr. Brewer in California; and 
208° as observed by Descloizeaux in Iceland.” 
* ¢¢ American Journal of Science and Arts,” vol. xliv., Sep. 1867. 
M 2 
