Royal Society. i 4  g Joey 
size. Hence, it may not only be expected that the general out- 
line and the prominent physical circumstances shall be correctly 
delineated, but that the minuter points and peculiarities which 
are interesting to the topographer and the antiquarian shall be 
permanently marked and readily traced in these maps. 
LXXXI. Proceedings of Learned Socteties. 
ROYAL SOCIETY. 
May 2. Dr. Nixon communicated an account by Dr. Serres 
of a singular case of complete euphony cured by electricity. 
The subject was a young French officer, who at the battle of 
Dresden was in the act of giving the word of command, when a 
ball passed him, the effect of which on the air knocked him 
down, at the same time rendering him speechless, and for a day 
almost insensible. Two men near him were killed by the ball, 
which did not touch him. In the hospital at Dresden he par- 
tially recovered the use of his left side and hearing, which were 
impaired ; but all efforts to recover his voice were in vain, and 
he was discharged as an invalid. His hearing was still very 
confused, but his smell was preternaturally acute, and the 
smell of coffee was altogetlier intolerable to him. His tongue 
had contracted into a sinall protuberance in his mouth about 
the compass of an inch, and his left side continued benumbed, 
till he was prevailed on to’ be electrified by Mr. Tinman of 
Brussels. He had not been electrified above seven or eight times 
when his hearing was improved, and his tongue began to ex- 
pand. Mr. T. then passed shocks through his mouth and down to 
his stomach, when he hastily got up, and in a low voice returned 
thanks to the operator, and ran off to Amsterdam like a person 
deranged. He returned, however, in a few days perfectly cured 
in his voice, which is now better than it was before the accident ; 
but he still feels some pain in his left leg, and occasionally in 
foggy weather an oppression on the chest. But after eight 
months and twenty-five days he recovered his voice completely. 
Dr. Wollaston read a paper, containing his remarks on the 
glazier’s diamond, and an account of his experiments with that 
instrument. He discovered that the diamonds for cutting glass 
are all in a natural state, and not cut by the lapidaries; that the . 
natural angles of the stones are probably harder than the artifi- 
cial; that the surface of all cutting diamonds is curvilinear ; that 
the groove which they make (for it is not a scratch as com- 
monly supposed) on the surface of the glass is a tangent to the 
face of the diamond ; and that flint and other hard stones me 
Bb2 e 
