1 N n E X. 2,7 



Sugar-maph tree lap, yields a fine fpirit, Vol. I. prtf. p. v. — anJ excellent 

 vinegar, p. 73. ^t^ Acer fecckar'mum, d^nd Maple. 



Sulphuric and muriatic acids, of the iblutlon of iron in. Vol. IV. p. 457. 



Sumach tree fuppofed to yield the gum copal — propofed as a dye — the leaves 

 mixed by Indians with their tobacco, Vol. I. pref. p. ix. 



Sun, caufe of Ws rays producing heat, Vol. I. appendix p. 34 — his paral- 

 lax important to be known, ib. p. 42 — how to determine it, ib. and 

 appendix 40 — the parallax deduced from a comparilbn of American ob- 

 fervatlons on the tranfit of Venus widi thofe of Europe, p. 54 — me- 

 tliod for afcertaining it firll conceived by Dr. Halley, ib. — an eafy 

 mode of deducing the true time of the fun palling die meridian per 

 clock, appendix p. 47 — his diftance from the planets, p. 62 — parallaxes, 

 ^5> I'ii 75' 111 78 — do. explained, 103 — mean diftance from tlic earth, 

 ib. — horary motion, 86 — diameter, 52, 79, 84, loi — eclipfed, 113. 



, obiervaticMis on the tranfit of Mercury over the, Vol. III. p. 150. 



, eclipfes of, Vol. II. p. 239, 250. 



Sun-Jloivsr oil, account of, Vol. I. p. 234 — effiiy oil exprefllng it, 235. 



Siipplemiiitum indicis florae Laricaftrienfis, Vol. IV. p. 235. 



Surimim (torpedo of) defcribed, Vol. II. p. 166, 170. 



S-Jiamp, definition of the word. Vol. IV. p. 440. 



Stvatara, defcription of a grotto there. Vol. II. p. 177. 



Sivedcu, fome account of its climate. Vol. III. p. 52 — proportion of 

 deaths in, 59. 



Swedes unfuccefsful in viewing the tranfit of Venus in 1769, Vol. I. appen- 

 dlx p. 3. 



S'weet /prints of Virginia, obfervations on. Vol. II. p. 197. 



Siulmm'mg anchor to keep a veifel from off a lee fhore, propofed and defcrib- 

 ed, Vol. 11. p. 311. 



Syllables, obfervations on. Vol. III. p. 299. 



T 



Tadpoles falling in a fhower of rain, the caufe of, explained. Vol. II. p. 117. 

 Tar and hog's-lard ufeful to preferve grape vines. Vol. I. p. 164. 

 Tatham ( Ccl. ll'm.) his obfervations on the country below tlie falls of James 



river (Vir.) Vol. IV. p. 444. 

 Teeth and bones (foffil) account of fome found in Virginia, Vol. IV. p. 439. 

 Telegraph, an elfay on one. Vol. IV p. 162. 

 Temperat'ire (prefuinahle) in comets. Vol. I. appendix p. 29. 



of irelund, Vol. IV. p. 244. 



Tennejfee river, petrifaftions there. Vol. III. p. 2 19 — curioufly marked rocks 



on a branch or, ib. 

 Tejl (infallible) for detefting the prefence of arfenic, Vol. II. p. 214. 

 Tetanus, on the caufe and cure of. Vol. II. p. 225 — predifpofed by relaxa- 



tion, 227 — not confined to the human fpccies, 230. 

 Theory of thunder and lightning. Vol. II. p. 74. 



of water-fpouts. Vol II. p. loi. 



of the earth, queries and conjeftures concerning a, by Dr. Franklin, 



Vol. III. p. 5. 

 of water-mills, &c. obfervations on, by W. Waring, Vol. III. p. 144 



— continued, 319. 

 of calculating the aberration of the ftars, the nutation of tlie earth's 



axis, and the femi-annual equation, Vol. IV. p. 32. 



4 E 2 Thermometer, 



