C 612 ] 
Metals . Attracted more Erongly by. acids than by fulphurs, p. 33. When combined 
with iulphur may be feparated by applying an acid, which will unite with the metal, 
and feparate the fulphur, ibid. Separated from the acid in its metallic form by 
means of another metal which attradls the acid more flrongly, ibid. How to treat 
metal which is in the ore in the form of a calx, p. 34. How to proceed with the 
greater ipars and other earthy matters mixed with. metals, ibid. How to adt when 
the earthy matter diffolves in the acid, p. 35. Examination of a principle which is 
of great ufe in inveffigating the elements of mixed metals, ibid. Metals in mineral 
waters combined with no other fubflance but the vitriolic acid, p. 37. Peculiar pro- 
perty of metallic falts, how tried, p. 38. The oil of metals defined, ibid. 
Meteor . An unufual, deferibed, p. 157. Two iniiances of the like kind, p. 159. 
Meteors . The air very full of them during an eruption of Vefuvius, p. 63. 
Meteorological regifler kept at Manchefler in 1774 and 1775, p. 348. 
Meteorology . A diary kept at Fort St. George, on the coafl of Coromandel, p. 246, 
Journal of the weather at Montreal in 1778 and 1779, p. 272. Journal kept at the 
houfe of the Royal Society in 1779, p* 280. 
Mills. Mode of eflimating the advantages of any particular kind of mills for prefling 
iligar-canes, p. 318. 
Mift. Mr. Cockin’s account of an appearance in a, p. 157. Two mentioned by Dr. 
Prieflley, p. 159. And one mentioned by Don Ulloa, p. 160. Explanation of that 
obferved by Mr. Cockin, ibid. 
Monjiers. Great variety of, p. 327. 
Moon. Agronomical obfervations relating to the mountains of the, p. 307. Difference 
betwixt Galileo and Hevelius about the heighth of the lunar mountains, p. 309. 
Method of finding the heighth of a lunar mountain from obfervations made when fhe 
is not in her quadrature, p. 312. Heighth of the lunar mountains generally much 
over-rated, p. 317. Thermometrical experiment to render the heat of the light of 
the, vifible, p. 383. 
Motion. The principles of progreffive and rotatory, inveiligated, p.348. 
N. . .. 
Nairne , Mr. His account of the effedts of eledlricity in fhortening witeS, p. 334. 
Needle. Variation of the, obferved at the Royal Society^ houfe in Jbly 1779, p. 303. 
Dip of the, obferved at the Society’s houfe in 1779*, p. 306. 
Nerves. Suppofed to be affedted by the poifon of Ticunas, p. 190. Experiments to 
determine whether it be fo, p. 191. 198..201, 202. General refledlions on diforders- 
commonly called nervous, p. 203. Not affedted by the water of the Lauro-Ceraftrs, 
P- 2I 7 * 
Nitre. The nitrous tefl applied to the examination offea air, p. 334. And of air at 
lanil, p. 359. _ , 
y . Ojjifieatien* 
