MEMORANDA. 153 
sults of changes undergone by a living being in the “ cycle 
of its existence,” and yet we do not, at least in some instances, 
perceive that the two are so intimately associated. 
Another point on which my reviewer takes me to task is 
my scepticism as to the existence of what I suppose he would 
term a “vital principle.” In this case I have been done a 
gross injustice. By the suppression of a portion of a sentence 
IT am made to assert that all the phenomena which living 
beings present can be explained by physical laws. The writer 
observes—“ Dr. Lawson’s objection to the statement that 
vital operations are not to be explained by reference to the 
known laws of force is certainly trivial and unnecessary.” 
Could anything be more unfair than this? In my preface to 
the work under notice I wrote—“‘ When he assumes that 
vital operations are not to be explained by a reference to the 
known laws of force, as it exerts itself through matter, and are 
only explicable on the supposition of a vital power, we must 
decidedly express our dissent.” 
Here, assuredly, is no advocacy of the view imputed to me 
in the notice, but simply an expression of disbelief, 7. e. of no 
belief whatsoever. I have always opposed the doctrine of a 
vital force as one of those medieval “ Will o’ the wisps” 
which, by leading men from real facts, induced them to satisfy 
their minds with mere terms, like phlogiston, phusis, catalysis, 
&e. But, on the other hand, I am not one of those who be- 
lieve that we are yet in acondition to explain life thoroughly. 
It is my opinion, however, expressed elsewhere,* that we are 
making rapid strides towards an elucidation of the mystery of 
life. Impartial readers must at once perceive that either my 
reviewer was bent upon my utter annihilation, and allowed his 
intelligence to be swayed by bias, or possibly fancied that the 
impetus of his strictures lent an air of criticism to his com- 
position. 
Feeling that assertions which, to a certain extent, impugn 
one’s character as a teacher of science, demand a distinct and 
unequivocal repudiation, and apologising for the length of 
this reply.—I am, &c., Henry Lawson, M.D., Co-Lecturer 
on Physiology and Histology im St. Mary’s Hospital Medical 
School. 
[Out of respect for Dr. Lawson as an editor we insert his 
letter. Having handed it to the gentleman who wrote the 
review, we give an extract from his reply ; and as the matter 
is not one tia at can further interest our readers, we must here 
close the controversy. 
* Vide ‘A Manual of Animal Physiology,’ p. 12. 
