t 49 8 ] 
D. 
D'Alembert. See Rotatory Motion. 
Darwin , Dr. Erafmus. See Artificial Spring. 
Deal Rods , table cf the expanfion of, with obfervations, p. 437 * •^■ re i*P ro P er 
very accurate meafurement, p. 438. 
De la Lande. See Wires. 
De Luc, Mr. See Specific Gravities. 
Double Stars. Catalogue of, by William Herfchel, Efq. p. 46. Method of pointing 
out thofe ftars in this collection which are not in Mr. Flamllead’s Catalogue, p. 4 1 . 
and of applying it, ibid. Precaution to be obferved where other ftars are very near 
thofe to be pointed out, p. 42. The obferver ftrould be furnifhed with Flamftead’s 
Coeleftial Atlas, which mull have the ftars marked from the author’s Catalogue, p. 43. 
Precaution in relation to examining the ciofeft of the double ftars, ibid. All the 
obfervat ons in this Catalogue are fuppofed to be made vvith a power of 460, unlefs 
marked otherwife, p. 45. Method of taking the meafures of the diftances, ibid. 
Sets Micrometer. Catalogue of double ftars, p. 47. Firftclals, ibid. — p. 65. Second 
clafs, p. 65 — 78. Third clafs, p. 78 — 90. Fourth clafs, p. 91 — 105. Fifth clafs, 
p. 103 — xi8. Sixth clafs, p. 118—126. Additional errata to the Catalogue of 
Double Stars in vol. LXXII. p. 126. See Variable Star. 
E. 
See Caribbee 1 <*. 
Eagle -fione. See Router. 
Earthquakes ■ 
1 , mete . 
Eclipfes. See AJironomicai ^ vations. 
Equatorial Micrometer, Mr. Sn.^aton’s recommended, p. 348. 
Euler, M. Leonhard. See Rotatory Motion. 
■ M. John ..ilbert. See Ditto. 
Expanfibility , observation on that of glafs, with Mr. Cumming’s pyrometer, p. 43 1 ^ 
See Deal Rods. 
F 
tergu/on. See trillion. 
Fixed Air and Water appear to confift of the fame ingredients, p. 296. See Air. 
For dye e , George, M. D. See Weight. 
jfriftion, on the Motion of Bodies affefted by, by the Rev. Samuel Vince, A. M. of 
Cambridge, p. 165. This branch of natural philofophy, nothwithftanding its im- 
portance 
