140 THE DESTRUCTIVE INFLUENCE OF 
of the degree of heat which proves fatal to various 
living things, by making it the subject of direct 
investigation. Others who have since defended 
similar views (including Pasteur in France, and 
Huxley and Sanderson in this country) have not 
made the thermal death-point of living matter a 
special subject of investigation, and have more or 
less distinctly confounded the issues of this question 
with that of the cognate though really distinct pro- 
blem, as to whether certain infusions could them- 
selves prove mother liquids and give independent 
birth to living matter. Dire confusion has thus been 
produced. A problem of a very simple nature has 
been made to appear very complex, whilst those who 
are able clearly to understand the real nature of the 
question at issue are left to marvel why the followers 
of Spallanzani have never ventured frankly to deal 
with the question of the limits of ‘vital resistance’ 
to heat, as Pouchet termed it. Certainly they 
have displayed, to say the least, a strange slug- 
gishness in reference to this exceedingly important 
problem. 
But apart from the fact that no Panspermatist, or 
declared opponent of spontaneous -generation, since 
the time of Spallanzani has fully and directly experi- 
mented upon the subject, I am all the more induced 
to call the reader's attention to the Abbe’s treatment 
