Numb. 4J r. 
PHILOSOPHICAL 
TRANSACTIONS. 
For the Month of j December, 1738. 
The C O N TENTS. 
L A Defcription of a Water-Level to he fix d to 
D a v i ss Quadrant , whereby an Obfervation may 
be taken at Sea, in thick and hazy Weather , with- 
out feeing the Horizon j by Charles Leigh* Gent . 
II. The Defcription and Ufe of an Apparatus added 
as an Improvement to Davis\r Quadrant , confuting 
of a Mercurial Level, for taking the Co-altitude of 
Sun or Star at Sea, without the ufual Ajfifiance of 
the fenfible Horizon , which frequently is ob feared* 
By the Same . 
III. A Letter from Mr. John Fergufon Surgeon, to 
William Che fd den, Efq ; Surgeon to Chelfea Col- 
lege, F. R. S. &c. containing an Account of the Ex- 
tirpation of part of the Spleen of a Man 
IV. A Letter from Benjamin Cooke, F, R. S. to Peter 
* Collinfon, F. R. S. concerning a Bali of Sulphur 
fuppofed to be generated in the Air . 
V. An Account of a Book intituled^ Obfervationes de 
Aere& MorbisEpidemicis>ab Anno 172.8, ad finetn 
Anni 1737, Plymuthi fadae, His accedit Opufcu- 
lum de Morbo Colico Damnonienfi. Audore Jo- 
anne Huxham, M. D. R. S. S. Drawn up by Tho. 
Stack, Af.fZXF.R.S, 
VL An 
