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oF ladies' fummer Viat9. Dr. Franklin's Experiments, Ob- 

 fervations, &c. 5th edit. p. 483, 5c feq. He obferves alfo, 

 ibid. p. 382, that a chimney painted black, when cxpofed 

 to the fun, will draw more ilrongly. We may add, that 

 black mould is a hotter foil for vegetables ; and garden- 

 walls, painted black, anfwer better for the ripening of wdll- 

 fruit, than thofe of lighter colours. 



Black, in matters of drefs, is the diflinguifhing habit 

 of churchmen and mourners. Some will have it, that the 

 common people among the Romans were clothed in black ; 

 whence the denomination given them of turhn pullata. 



Black, Josfph, m Bu/gmphy, a celebrated teacher of 

 chemiftry, was born at Bourdeaux, in France, in the year 

 1728. His father, who was a native of Belfall, in Ireland, 

 but of a Scotch family, carried on the wine trade at Bo'.ir- 

 deaux, and lived in intimacy with the famed baron Montcf- 

 quieu, who exprtfTcd his regret in ftrong terms on Mr. 

 Black's quitting Bourdeaux, when he retired from bufincfs, 

 as appears by feveral of his letters which are preferved by 

 the family. By his mother. Dr. Black was nearly related 

 to the wives of Dr. Adam Fergufon, and Mr. James Ruifcl, 

 profefforin natural philofophy at the univerfity of Edinburgh, 

 and owed probably much of his knowledge to the inflruc- 

 tion or information he obtained from them. In tbe year 

 1 740, his father fent him to Belfaft, that he might have the 

 education of a Britifh fubjeft ; and from his letters, he ap- 

 pears to have been fatisfied with the progrefs he made there. 

 In 1746, he went to Glafgovv, where he applied to the 

 ftudy of medicine, but particularly to chemiltry, into the 

 knowledge of which he was initiated by Dr. Cullen, who 

 then gave lectures there on that branch of fcicnce. Under 

 his direction he made fuch progrefs, that, in 1756, when 

 Dr. Cullen removed to Edinburgh, Black, who had previ- 

 oufly taken his degree of doi?ior, fucceeded him as profcflbr 

 in medicine, and leilurer in chemiftry. That he was quali- 

 fied to fill this office, he had (hewn by an ingenious effaj', 

 containing experiments to inveiligate the nature of magnefia, 

 quicklime, and fome other alkaline fubftanccs, recommended 

 as folvents of the Hone in the bladder. In the courle of 

 thefe experiments he demonftrated the exiftence of an aerial 

 fluid, which he called fixed air, the prefence of which gave 

 mildnefs, and its abfcnce caufticity, to alkalies and calcareous 

 earth ; a difcoveiy which laid the foundation of the improve- 

 ments fince made in our knowledge of gafes, or aerial bodies, 

 by Friellley, Cavendifli, Lavoifier, and other chemifts. The 

 elTay, containing the account of thefe experiments, was pub- 

 lilhed in the fecond volume of " Efi'aysphyficaLand literary," 

 in 1756. The following year he further enriched his favour- 

 ite fcitnce with his experiments on latent heat, which is 

 found to ex. 11 in all bodies ; explaining in a fatisfaftory 

 manner the connexion of heat and fluidity, by which he fo 

 eftablifhed his reputation, that on Dr. Cullen's being pro- 

 moted from the chemical to the medical chair at Edinburgh, 

 in 1765, he was unanimouiiy chofen to fucceed him as pro- 

 feffor in chemifti-y there. His tim.e was now dedicated, 

 and with increafed ardour, to imparting the knowledge he 

 had acquired to his numerous pupils ; and as he was per/eftly 

 mafter of the fubjefts on which he lectured, his dotlrines 

 were fo clearly explained, as to be eafily underftood by his 

 auditors, many of whom took complete copies of his lec- 

 tures. By this means the knowledge of the difcoveries he 

 had made, became widely difiuftd, and his claim to them 

 fecured to him, which might otherwife have been afiigned 

 to thofe who improved and extended them. Having thus 

 laid the ground-work for the improvement of the art, he 

 feems to have been contented, without attempting to pulh 

 liis difcoveries further. Satisfied with the attention paid 



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him by his pupils, and the gradual extenfion of his fame» 

 of which he received daily proofs, he took little notice of 

 what Prieftley, Lavoifier, and other philofophical ciieraills, 

 were doing, or only noticed them when they had neg. 

 lected making thofe acknowledgments to him he knew to 

 be his due. Dr. Robifon, who had been his pupil, and 

 has lately publiflicd his lectures, with an account of his hfe. 

 attributes this apparent apathy to the ill ftate of his 

 health, which, for feveral years before his death, did not 

 permit that degree of application and ftudy, which the far- 

 ther extenfion of his difcoveries would have required. " The 

 flighteft cold," he fays (Preface to the Lectures, p. Ix.), 

 " the moft trifling approach to repletion, immediately af- 

 fefted his breafl:, occafioned feverilhnefs, and, if continued 

 two or three days, brought on a fpittiiig of blood. In this 

 fituation nothing rettored him but relaxation from thought, 

 and gentle exercife. The fedentary life, to which ftudy 

 confined liim, was maniftftly hurtful ; and he never allowed 

 himlelf to indulge in any intenfe thinking, or puzzhng re- 

 fearch, without finding thefe complaints fenfibly increafed." 

 Hence, though he had the honour of being elected one of 

 the foreign afi'ociates of the royal academy of fciences at 

 Paris, and member of the imperial academy at Peterftjurgh, 

 he fent no commur.ications to either of thofe learned focie- 

 ties. As he ranked high among the teachers of chemiftr)', 

 and his name and charafter were extended over Europe, his 

 pupils were numerous, and continued increafing for the 

 whole time he lectured, more than thirty years. In the 

 year 1774, he fei.t to the royal fociety in London, his ob- 

 fervations on the effect of boiling upon water, in difpofing 

 it to freeze ; and, in 1701, the Royal Society at Edinburgh 

 pubhftied his analyfis of the waters of fome hot fprings in 

 Iceland, in the third volume of their Tranfadions. In this 

 paper, which is drawn up with great accuracy, he treats of 

 the formation of the filicious ftone, which is depofited by 

 thefe fprings. Kis conftitution becoming more and more 

 feeble, from the frequent returns of his complaint, he was 

 firft obliged to make ufe of an affiftant in his leftures, 

 and at length, to give them up altogether ; the fmalleft. ex- 

 ertion bringing on a fit of hssmoptoe. " But he fecmed," 

 Dr. Robifon fays (Preface, p. 73.), " to have his complaint 

 almoft under command, fo that he never allowed it to pro- 

 ceed far, or to occafion any diftrcffing illnefs, and fo fpun his 

 thread of life to the laft fibre, guarding againft illnefs by re- 

 ftrifting himfelf to a moderate diet, and meeting his increafing 

 infirmities with a proportional increafe of attention and care." 

 On the 26th of November 1799, and in the 71ft year of his 

 age, he died fuddenly, without any previous warning. Be- 

 ing at table, with his ufual fare before him, fome bread, a 

 few prunes, with m.ilk and water for his drink, having the 

 cup in his hand, refting on his knees, he expired fuddenly 

 in that pofture, the cup remaining in his hand, and his 

 countenance fo compofed and placid, that his fervant at firll 

 imagined he was fallen afleep. He was of a chearful and 

 fociable difpofition, and, as his mind was well flared with. 

 knowledge, an entertaining companion. His company was 

 therefore much courted ; and, as his circumftances were af- 

 fluent, he dedicated as much of his time to the pleafures of 

 fociety, as was confiftent with his avocations. He was never 

 married ; he therefore left the principal part of his fortune, 

 which is faid to have been confiderable, among the chil- 

 dren of his brothers and fiftcrs. Gen. Biog. Diet. LeAures 

 of the Elements of Chemiftry. 



Black, in Heraldic Engravings, is cxprefled by crofs 

 lines, and in emblazoning, is termed for commonei-syi/^A-, for 

 peers diamoiuf, and for fovereigns and princes fisUirn. 



Black, iu the Manege, A hoiic of a deep, Ihining, 



and 



