VI 
CONTENTS. 
XXXVin. An Account of further Difcoveries in Air. By 
the Rev. Jofeph Prieftley, LL.D. F. R. S. in Letters to 
Sir John Pringle, Bart. P. R. S. and the Rev. Dr. 
Price, F. R. S. p. 384 
XXXIX. An Account of the Gymnotus Ele(ftricus. By 
John Hunter, F. R. S. P* 395 
XL. Some Obfervations upon Myrrh, made in Abyflinia, 
in the Tear 1771, and fent to William Hunter, M. D. 
with Specimens^ in February, 1775. James Bruce, 
Efq. p. 408 
XLI. An Account of a curious Gianfs Caufeway^ or Group 
of angular Columns, newly difcovered in the Euganean 
Hills, near Padua, in Italy. In a Letter from John 
Strange, Ffq. F. R. S. to Sir John Pringle, Bart. P.R.S. 
p. 41 8 
XLII. Obfervations on the Difference between the Duration 
of Human Life in Towns ajtd in Country Parijhes and 
Tillages I By the Rev. Pvichard Price, D. D. F.R. S. 
Communicated by Dr. Horfley» p. 424 
XLIII. Experiments on Animals and Vegetables, with re- 
fpcSl to the Power of producing Heat. By John Hun- 
ter, F. R. S. p. 446 
XLI V. A Comparifon of the Heat of London and Edin- 
burgh. By John Roebuck, M. D. F. R. S. in a Letter 
to William Heberden, M. D. F. R. S. p. 459 
XLV. Experiments in an heated Room. By Matthew 
Dobfon, M. D. In a Letter to John Fothergill, M. D. 
F. R. S, p. 463 
XLVI. Cal- 
