in Reply to Dr. John Davy. 251 
from suggesting one which would have seriously disparaged 
it. 
But the whole amount of the charge (if charge it can be 
called) which I had brought against Sir H. Davy, consisted 
in attributing to him some degree of fickleness or caprice in the 
abandonment of a preconceived opinion, apparently without 
sufficient reason. 
How far the motive suggested for this change of opinion 
may be consistent with the character of the individual himself, 
(which is now a matter of history, and not a fit subject for in- 
discriminate panegyric,) will best be appreciated by those who 
were most in his intimacy. 
For my own part, as a warm admirer of his genius, though 
gathering my impression of his sentiments and disposition 
from public report; without any recollections from personal 
acquaintance to correct the impressions thus received, but 
with every disposition to extenuate the foibles of so great a 
philosopher ; I shall sincerely rejoice, if the book now pub- 
lished by his brother, a small part alone of which I have as yet 
perused, should succeed in its proposed object of elevating the 
personal reputation of the individual, and thus convince the 
world that my interpretation of his conduct in this trivial par- 
ticular has been erroneous. 
Still, however, Dr. Davy must excuse me, if, from all that 
has yet appeared, I persist in regarding his brother’s change 
of opinion in this instance a matter rather of taste than of 
judgement. 
In the memoir on volcanos referred to, Sir Humphry di- 
stinctly admits that his previous theory is fully competent to 
explain all the phznomena*, although he concludes by 
assigning a preference to the other explanation as recommend- 
ed by greater simplicity ; a sentence which, as his biographer 
Dr. Paris justly observes (Life, p. 247), must be admitted to 
be rather equivocal. In his Consolations of a Philosopher he 
is somewhat more explicit, yet even there the only reason he 
assigns for preferring the theory of central heat is vagueenough, 
being, as he thinks, ‘more agreeable to the analogies of things.” 
Having, therefore, looked in vain in either of these records 
of his sentiments for any attempt to show in what way “ this 
* “ Assuming the hypothesis of the existence of such alloys of the metals 
of the earths as may burn into lava in the interior, the whole phenomena 
may be easily explained from the action of the water of the sea and air on 
these metals; nor is there any fact, or any of the circumstances which I 
have mentioned in the preceding part of this paper, which cannot be easily 
explained, according to that hypothesis.””—Memoir on the Phenomena of 
Volcanos, by Sir H. Davy, Phil. Trans. 1828. [or Phil. Mag. and Annals, 
N.S. vol. iy. p. 85—94. Eprr.] 
