[ 443 3 
A N 
INDEX 
TO THE 
SEVENTY-EIGHTH VOLUME 
OF THE 
PHILOSOPHICAL TRANSACTIONS. 
A. 
/ACCOUNT of experiments made by Mr. John M‘ Nab, at Albany Fort, 
Hudfon’s Bay, relative to the freezing of nitrous and vitriolic acids, p. r66. 
Account of an experiment to determine the effedl of fait upon the expanfion of water 
by cold, p. 3 1 1. 
Acid, vitriolic , experiments on, p. 177. Its effect upon the freezing point of water, p. 
305. Nitrous add, its effedt on the freezing point of water, p. 306. EfFedt of the 
Muriatic acid in lowering the freezing point of water, p. 307. 
Acidity , obfervations and expeiiments on the principle of, p, 147, 313. 
Aerial Moijlure, devaporation of, p. 49. 
Air , frigorific, experiments oa the mechanical expanfion of, p. 43. Air, fufc.eptible of 
heat, p. 56. Fixed air contains about half its weight of water, p. 152. On the 
converfion of a mixture of dephlogiilicated and phlogifticated airs into nitrous acid by 
the eledtric fpark, p. 26 r. Nitrous air contains water, which contributes to the 
formation of fixed air, p.318. If phlogifticated and light inflammable air be pre- 
fented to each other at the inftant of their leparation from folid or liquid fubftances, 
and before their particles have receded from each other, they readily combine and 
Vol, LXXVIII. N n n generate 
