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chimney. The Alchemists used the Athanor for digestions, &c. 

 but wherever a high heat was required, tliey employed the Blast 

 furnace, till Glauber added a long tube to the vent-hole of Ge- 

 ber's furnace. In his treatise on Philosophical furnaces, (a very 

 curious work which contains many inventions which have of 

 late years been rediscovered, as Woolfe's apparatus, the (a) AVater- 

 lute,' the use of steam to heat a larger mass of fluid, &c.) he gives 

 an interesting account of his contrivance. After expatiating on 

 the vexation wliich the unfortunate alchemist continually suffered 

 in his experiments with the Blast furnace, where he was exposed • 

 to poisonous fumes and the mortification of seeing his hopes dis. 

 appointed by the failure of his crucibles, he tells us that he 

 determined iu a fury to resign chemistry, he sold his bellows 

 and was disposing of the remainder of his apparatus by throw- 

 ino- it out of the windows, when he found in a broken crucible 

 some grains of silver which he could not sell without fusing 

 them into a mass. After some meditation he contrived a fur- 

 nace which was so convenient that it tempted him to resume 

 his favorite pursuit. Glauber's furnace was gradually modified 

 by succeeding Chemists, Cramer and Boerhaave have described 

 various forms of them, but they were not able to excite very 

 strong heats, as the former directs Assays of Iron ore, and 

 some of Copper to be made with the assistance of bellows open- 

 ing into the ash-pit. Pott was the first who conceived the pos- 



(a) Glauber used lead, as his apparatus was red hot, and some of his experiments with 

 it are very curious, in one, when attemi.ting to extract a spirit from gold (for all his 

 chemistry was occupied wiUi the discovery of remedies,) he threw into it successive 

 portions of aurum fulminans, and observed the production of water by its explo- 

 iion. 



