68 
his collection was deposited in the Philosophical Society at York, 
then newly established. 
I now proceed to notice our deceased Foreign Members. 
Fran¢ois-Dominique de Reynaud, Comte de Montlosier, was born 
at Clermont in Auvergne, April the 16th, 1755, the year of the ce- 
lebrated earthquake of Lisbon. He was the youngest of twelve 
children of a family of the smaller nobility of that province, and was 
remarkable at an early age for the zeal with which he pursued va- 
rious branches of science and literature. 
Count Montlosier must ever be considered as one of the most 
striking writers in that great controversy respecting the origin of ba- 
saltic rocks, which occupied the attention of mineralogists during the 
latter half of the last century ; and to which, in so large a degree, the 
progress and present state of geology are to be ascribed. The theory 
of the extinct voleanos of Auvergne, the subject of his researches, 
was the speculation which gave the main impulse to scientific curi- 
osity on this point. It is true that he was not the originator of the 
opinions which he so ably expounded. Guettard, in 1751, had seen, 
vaguely and imperfectly, that which it now appears so impossible 
not to see, the evidences of igneous origin in the rocks of that di- 
strict: and the elder Desmarest, whose examination of them began 
in 1763, had made that classification of them, which is the basis, and 
indeed the main substance, of the views still entertained with regard 
to the structure of that most instructive region. His map of the 
district, published in 1774 (in the Transactions of the Academy of 
Paris for 1771, according to a bad habit of that body still prevail- 
ing), exhibits the distinction of modern currents of lava, ancient 
currents, and rocks fused in the places where they now are, which 
distinction supplies a key to the most extraordinary phenomena, 
while it reveals to us a history more wonderful still. But striking 
and persuasive as this view was, and fitted, apparently, to carry 
with it universal conviction, the theory which it implied, collected, 
as it seemed at the time, from one or two obscure spots in Europe, 
was for a while resisted and almost borne down by the opposite 
doctrine of the aqueous origin of basalt ; which came from the school 
of Freyberg, recommended by the power of a connected and com- 
prehensive system,—a power in science so mighty for good and for 
evil. Montlosier’s Essay on the Voleanos of Auvergne, which ap- 
