250 Prof. Daubeny on Sir H. Davy’s Theory of Volcanos, 
After noticing his brother’s change of opinion with respect 
to the cause of volcanos, Dr. Davy proceeds as follows: 
‘It would hardly be supposed, that my brother’s motives 
for modifying his views respecting the nature of volcanic ac- 
tion, as above stated, and for giving up in part a brilliant 
hypothesis, could be misinterpreted, and referred to an un- 
worthy feeling ; yet this, to my surprise, has been done, and 
even by Dr. Charles Daubeny, Professor of Chemistry in the 
University of Oxford. This Gentleman, in defending the 
hypothesis. which he advocates, and which is precisely my 
brother’s early hypothesis, comparing Sir H. Davy’s early 
views with his later, says, ‘ The authority of Sir H. Davy may, 
I conceive, on this occasion, be fairly pleaded against himself, 
and the weight of his zpse dixit in the two latter years of his 
life be viewed as counterbalanced by the contrary judgement 
he had pronounced, apparently on the same evidence, at an 
earlier period; neither is it inconsistent with what we know 
of his character, to suppose that he should have acquired a 
distaste for the theory in question, when he found it seized 
upon and illustrated by an humble [humbler] class of in- 
quirers.’ ” 
* This I would remark is neither generous nor just, nor even 
reasonable criticism. It is not generous to assign to unworthy 
motives, a meritorious act; for so surely may be viewed the 
relinquishing such an hypothesis by the author of it, when he 
found it not sufficiently supported by facts. It is not just, be- 
cause not true, that he merely gave his zpse dixit against his 
early hypothesis ; in my brother’s observations on volcanos, as 
I have mentioned, he assigned his reasons for so doing, con- 
sisting chiefly in want of the positive evidence which he ex- 
pected to have met with in examining into the phenomena of 
active volcanos, provided the chemical theory were true. And 
least of all, is the criticism reasonable: it is almost absurd to 
suppose that my brother would relinquish his hypothesis be- 
cause approved of and advocated by others. Dr. Daubeny 
might as well have fancied that he would have changed his 
views respecting chlorine, and the metallic bases of the fixed 
alkalies, as soon as they were seized upon and illustrated by 
an humbler class of inquirers.” 
The asperity of the above remarks seems but little warrant- 
ed by the occasion which has called them forth. 
Had Dr. Davy been aware of the sentiments I have always 
expressed relative to his deceased brother, he would have 
acquitted me of any wish to depreciate his memory, and would 
have felt that even in the absence of any other mode of ac- 
counting for this change of opinion, I should have abstained 
