230 Natural History of Volcanos and Earthquakes. 
any; but he included in his writings, species from ail countries. 
His chief works on birds and on fishes—which are still valuable 
from the correctness of the plates—he did not live to finish, and 
they were edited and published by Ray. Of his character, a 
biographer thus speaks : 
“ And now, having mentioned the diligence of this great man, 
let me add that it was such, and his labors so incessant in studies, 
that he allowed himself little or no time for those recreations and 
diversions which men of his estate and degree are apt to spend 
too much of their time in; but he prosecuted his design with as 
great application as if he had been to get his bread thereby. All 
which I mention not only out of the great respect I bear to Mr. 
Willoughby’s memory, but for an example, as has been before 
recommended to persons of great estate and quality: that they 
may be excited to answer the ends for which God gives them 
estates, leisure, parts, and gifts, or a good genius, which was not 
to exercise themselves in vain and sinful follies ; but to be em- 
ployed for the glory and in the service of the infinite Creator, and 
in doing good offices in the world, especially such as tend to th 
credit and profit of their own families.” . 
(To be continued.) 
Arr. IL—On the Natural History of Volcanos and Earth- 
quakes,* by Dr. Gustav Biscuor, Professor of Chemistry 2 the 
: University of Bonn. Communicated by the Author. — - 
I. Are volcanic phenomena capable of a satisfactory explanation 
Jrom the increase of temperature towards the centre of the earth, 
or can chemical processes be admitted with greater probability 
to be the cause of volcanic action ? 
On inquiring into the cause of voleanic phenomena we must 
not forget, says Von Humboldt,t that the arrangement of volea 
nos sometimes in circular groups and sometimes in double lines, 
is the most decided proof that their action is not dependent om 
ee Os Eee er 
On the structure and action of volcanos in various parts of the earth, 9 oe 
Abhandlungen der Kénigl. Acad. d. Wissensch. zu Berlin, 1822 and 1823, P- 
and in Jameson's Phil. Jour. vol. v. p. 223 
