[ 449 ] 
N. 
Native Iron, account of a mafs of, found in South-America, p. 3 7, 183. 
Nicholfon , William, on an inftrument which, by the turning of a winch, produces the 
two dates of electricity without friction or communication with the earth, p. 403. 
Nitre, fpirit of, fubjedt to aqueous and fpirituous congelation, p. 166. The effect of 
nitre in lowering the freezing point of water, p. 281, The ice of folutions of nitre 
very different from common ice, p. 283. Nitre and common fait, the etfedh of a 
compound folution of, in lowering the freezing point, p. 299. 
Nitrous acid, its effedt on the freezing point of water, p. 306. 
Numbers , On fome properties of the fum of the divifors of, p. 388. 
\ 
O. 
QlJ eruptions on motion in general, p. 23. On the heat of wells and fprings in the ifland 
of Jamaica, and on the temperature of the earth below the furface in different climates, 
p. 53. Obfervations made at Brighthelmftone, with a view to afcertain the tempera- 
ture of the fea as a bath, p. 64. On the manner in which glafs is charged with the 
ele&ric fluid, and difcharged, p. 121. Obfervations and experiments relating to the 
principle of acidity, the compofnion of water, and phlogifton, p. 14;, 313. Ob- 
fervations on the irritability of vegetables, p. 138. Obfervations on the natural hiftory 
of the cuckoo, p. 2 19. 
r. 
ParUtaria , obfervations on the, p. 162. 
ParnaJJia , obfervation on the, p. 163. 
Phlogifton , experiments and obfervations on, p. 147, jij* 
Planet, on the Georgian, and its fatellites, p. 364.. The light of the fatellites of this 
planet is, on account of their great diftance, uncommonly faint, p. 376. The fecond 
fatellite brighter than the fir ft, but the difference not confiderable, ibid. The fitua- 
tionsof the 01 bits of thefe fatellites do not materially differ, p. 378. They will be 
eclipfed about the years 1799 and 1818, ibid. Probably not lefs than thofe of 
Jupiter, ibid. 
Platina , duft of, mixed with gold, found in the kingdom of Santa Fede Bogota, p. 41^ 
188. 
Prieftly , Jofeph, LL.D. on the principle of acidity, the compofition of water, and 
phlogifton, p. 147, 313. 
> Problems , 
