INDEX. 27 



N'uoJa (Lewis) his method of preferving fubjcifls in fpirits, Vol. I. p. 244. 



N'ine-Liller, a bird, dci'ciibed, Vol. IV. p. 124. 



Nitre found and made, Vol. I. pre/, p. xii. — mixed with water produces 

 heat, and with fnow, intenfe cold, appemlix 33 — other properties of, 

 Vol. IV. p. 140. 



Nitric acid, its compofilion, obfervations and experiments on the producftion 

 of. Vol. TV. p . 472. 



Nitrogen ga<, what proportion in the atmofpherc. Vol. IV. p. 128 — obfer- 

 vations on it, p. 6, Sec. 418. 



Non-Jejcrir t iirunvdls, rerriains of, Vol. IV. p. 248, 259, 511. 



Normar.die (Dr. John De) his analyfis of the chalybeate waters of Briftol 

 (Pennf.j Vol. I. p. 303. 



Norrilon ohfcrvatory (Pennf.) tranfit of Venus in 1769 obferved at, Vol. I. 

 p. 8, 13 — its lat. fixed, 22, and Ion. 59, appendix p. 2 — account of 

 the terreftrial meafurement of difference of longitude between this ob- 

 fervatory and that of l-'hiladelphia, appendix p. 5. 



North- Ameiicn, difealcs common to, Vol. III. p. iii. See America. 



North-Carolina, defcribed, Vol. III. p. 47 — remains of a volcano in, p. 231. 



Nortb-rveJ] luinds, why lefs frequent, Vol. I. p. 275. 



North-nnejlern Territory, recapitulation of fine weatlicr there during a certain 

 period. Vol. IV. p. 347. See Mnjhingum, Cincinnati, Niagara. 



Notatir.n (a neiu) oi rnuHc, Vol. HI. p. 139. 



Noxious vapours, in fubterranean places, how eafily diffipated, Vol. III. p. 



324- 

 Numbfjh, or torporific eel, defcribed, Vol. II. p 1 70. 

 Nutation of the earth's axis, how to calculate it, Vol. IV. p. 51. 



o 



0. (B.) his defcription of a new machine for cutting files, Vol. I. p. 300. 

 Oats deftroy the wild garlic, enemy to wheat. Vol. I. p. 242. 



(American) their qualities, Vol. I. p. 192. 



ObjeSis of the Amer. Philof. Soc. Vol. I. pref. p. xv. 



Occuliation of Atdelaran by the moon obferved at Wafliington in 1793. Vol. 



IV. p. 48. 

 Ocean, its temperature at certain depths, Vol. III. p. 90 to 96. 

 Officers of the r\. P. S. Vol. I. p. xii — Vol. II. p. xxiii — Vol. III. p. xxviii. 



Vol. IV. p. xiv. 

 Ohio river, great bones found there, Vol. III. p. 219 — Vol. IV. p. 511 — 



ancient hii.roglyphics there, p. 195 — very denfe but not unwholelome 



fofc,s on the nvcr, p. 225 — thermometrical obfervations made tnere, p. 



3^0 — the dail rile and tall of its water, 340. 



falls of, lemarkable ior petrifaftions. Vol. III. p. 218. 



0/ ' how atfeded on a furface of w.iter, Vol. II. p. 310. 



— mixed with water, a remarkable phenomenon produced from. Vol III. 



p. 14 — explanations ot it attemp:ed, ib. 



— of cotion-fetd, its virtues, and how obtained, Vol. I. p. 135. See 01. 



BoniLac. 



4 D Oi/of 



