
CHAP EER EX 
THE LIMITS OF VITAL RESISTANCE TO HEAT: LATER 
OBSERVATIONS 
S° far we have been referring to the influence of 
heat upon living matter when it is suddenly 
applied to an altogether unaccustomed extent. This 
is the mode of operation with which we are specially 
concerned; since with a view to the interpretation of 
experiments on the origin of life question, we wish 
to know the effects of great heat suddenly applied 
upon organisms or their germs that have been 
accustomed to ordinary atmospheric and aquatic 
temperatures. 
On the other hand, it should be pointed out that 
Conferve and other low algoid organisms have been 
found living in hot springs at comparatively high 
temperatures ; although the very highest of the 
recorded temperatures of these hot 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.!' The highest tempera- 
tures cited which are at all trustworthy in which 
Conferve or allied organisms have been met with 
are thus summarised by him :—‘‘ The statements 
1 American Journal of Science and Arts, vol. xliv., Sept. 1867. 
53 
