[ 497 ] 
occurred in the fourth, fifth, fixth, and feventh experiments, accounted for, p. 317 — 
321. Recapitulation of the refults of Mr. Hutchins’s expeiiment?, p. 321. Re- 
marks on the contraction of quickfilver in freezing, p. 322 — 324. On the cold o 
the freezing mixtures, p. 324 — 328. 
uickjtlvery Hiftory of the Congelation of, by Charles Blagden, M. D. p. 329. That 
it freezes in a degree of cold not exceeding that which fometimes occurs in the north- 
ern parts of Europe, and frequently in the more rigorous climates of Afia and America, 
proved by Mr. Hutchins, ibid, and ought to be ranked among the perfect metals, p. 
329. Thofe metals arranged according to their fpecific gravity, p. 330. hi. Braun, 
profeflor of philofophy at Peterfburg, firft proved thatquickfdver could be made folid 
by a diminution of its heat, ibid, which he difeovered by experiments made for 
a different purpofe, fuggefted by Dr. John Ernelt Zeiker, p. 33 1 * Refult of thoie 
experiments, p. 331, 332. Of which M. Braun prefented an account to the Peterf- 
burg Academy, publifhed foon afterwards under the title of “ De admirando frigori 
artificiali difrertatio,” p. 333. The miftakes which he retains in his “ Supplementa 
de Congelatione Mercurii,” publiflied five years afterwards, p. 334. Notwithllanding 
which, the greateft part of our prefent knowledge of the lubjeCt is to be Sound in his 
writings, p. 33^. Tranflation of the account of M. Blumenbach’s experiment, p. 
236 — ’338. Difference between M. Bkimenbach’s and Profeflor Brauns folid quiek- 
filver, accounted for, p. 339. Mr. Hutchins renders quickfilver malleable at Hudfon’s 
Bay, p. 341. Dr. Lambert Bicker’s attempt to congeal quickfilver at Rotterdam, ibid. 
And Dr. Anthony Fothergill’s at Northampton, p. 34 2, Mr. Cavendifh and Dr. Blacks 
method of afeertaining the freezing point, the fame, but their apparatus different, p. 
34£. Appearances in Mr. Braun’s experiments accounted for, p. 346. Appearances in 
Mr. Hutchins’s ninth experiment accounted for, p. 347. Remarks on his thermometers, 
ibid. p. 348. See Snow. Experiments made at Hudfon’s Bay with two thermometers, 
to difeover what degree of cold the freezing mixture produced, p. 352. Obfervatmns 
thereon, p. 353. Extraft of a letter from Dr. Mat. Guthrie, concerning his experiments 
made at Peterfburgh for the congelation of quickfilver, p. 354* The confequences T 
duced by him therefrom, erroneous, and why, p. 355. Error in his method for tettiing 
the point of mercurial congelation, how to be obviated, p. 358. Mr. Cavendifh, by 
diluting the nitrous acid to a proper degree, at Hampfiead, rendered the cold of his 
frigorific mixture nearly as great as that of Mr. Hutchins’s at Hudfon’s Bay, p- 359. 
285 388. That quickfilver has frequently become folid by natural cold, demon- 
Iftrated, p. 360—36 3. Dr. Gmelin’s obfervations on the congelation of mercury in 
Siberia, with remarks, p. 361.-371* M - Maupertuis’s in Lapland, and M. Gau- 
tier’s at Quebec, p. 372. Mr. Andrew Hellant’s in Lapland, p. 373—3:8* The 
Abbe Chappe d’ Auterochc’s in Siberia, 378. M. Erick Laxmann’s in ditto, ibid. 
M. Pallas’s in ditto, p. 379—384* M- GeorgiV in ditto, p. 3 * 4 * The quv.kii.ver 
retained its fluidity at Prince of Wales’s Fort, Hudfon’s Bay, ibid. Let-cr from M. 
Von Elterlein giving an account of his freezing quickfilver by natural cold, p* 389* 
T t 25 LCtter 
