, Royal Society. 153 
In this paper he gives an account of the structure and chemical com- 
position of 330 calculi, which had either been purposely divided or 
accidentally broken in their extraction. The results are arranged in 
tables, exhibiting, in the order of their superposition from the centre, 
the consecutive deposits of which each calculus is composed. It ap- 
pears from these tables, that not less than two-thirds of all urinary 
calculi consist of the lithates, or have those substances for their nu- 
clei: whence Dr. Yelloly inferred the probability that a large pro- 
portion of them owe their existence to the previous formation of such 
a nucleus, and was led to suspect that carbonate of lime, although 
rarely found in a separate form in calculi, is not an unfrequent con- 
comitant of phosphate of lime. With the assistance of Dr. Prout 
and Mr. Faraday, he ascertained the presence of carbonate of lime in 
some of the specimens which were not previously supposed to contain 
it; a result which was confirmed by the analysis of several calculi 
from the collection of the Hunterian Museum, and also from the 
Museum of Guy’s Hospital. 
He presented to the Society, two years afterwards, a sequel to this 
paper, recording, in a tabular form, the analysis of 335 additional 
specimens, which had, in the interval, been divided*. The most re- 
markable fact noticed in this memoir, is the presence of silex in a 
few specimens. Dr. Yelloly finds reason to believe that the ave- 
rage number of calculous disorders occurring in Scotland has been 
much underrated ; that, on the other hand, the proneness to these com- 
plaints is very small in Ireland; and tliat, on the whole, 2 much 
larger proportion of calculous cases occurs in towns than in the 
country. 
For some years before his death, Dr. Yelloly had relinquished 
practice, and resided at Woodton Hall, near Bungay ; his attention 
being chiefly turned to agricultural pursuits. From thence he re- 
moved, about two years ago, to Cavendish Hall, in the neighbour- 
hood of Clare, in Suffolk ; where, in February last, his valuable life 
was suddenly terminated by an attack of apoplexy, while taking an 
airing in his carriage. 
Lizurenant WELLSsTEAD, of the Indian Navy, was a distin- 
guished traveller in the East. He was the author of a notice on the 
ruins of Berenice, of a journey into the interior of Oman, and of a 
journey to the ruins of Nahab el Hajar, published in the 'Transac- 
tions of the Royal Geographical Society. He died in the month of 
October last. He received a severe injury on the head while in 
India, which was the remote cause of his early and lamented 
death. 
Mr. Hennext, the chemical operator at Apothecaries’ Hall, lost 
his life by an extraordinary accident ; he was mixing a large quan- 
tity of fulminating mercury for the service of the army in India, and 
being desirous that it should be of an uniform colour, the whole was 
placed in a Jarge evaporating dish ; as he was stirring it, an explosion 
of the whole took place, which was attended with his complete de- 
struction, many parts of the body being thrown to a considerable di- 
* Phil. Trans, for 1831, p.415. 
