Royal Imtllidlm. 1S3 



and a recapitulation of the prominent events of the period. When 

 alchemy was at its acme, during the fifteenth and sixteenth cen- 

 turies, many useful members of society were entrapped by its 

 golden prospects. Among them was that admirable artist, Maz- 

 zuoli of Parma, better known under the name of Parmegiano: 

 sickness and beggary were the reward of him and his associates. 



The zeal and activity in scientific pursuits, which has since 

 marked its progress in Europe, I^ecame manifest early in the se- 

 venteenth century, and the causes which Mr. Brande unfolded, 

 contributed to the splendour which it began to acquire, about 

 the end of that im.portant aera, in the general history of the world. 



Mr, Brande's second lecture embraced an account of the state 

 of chemistry at the opening of the eighteenth century, in which 

 the theories of combustion invented bv Beccher, Stahl, Rev, 

 and Mayow, were principally dwelt upon, and experimentally 

 illustrated. The system of Beccher, as enlarged and embellished 

 by his pupil Stahl, supposes inflammable bodies to contain a pe- 

 culiar volatile principle called phlogiston; flame is produced bv 

 tlic escape of this principle. Rey in 1630, and Mayow in 

 167-1, objected to the conclusions upon which the phiogistic 

 system was reared ; for bodies in general, they observed, became 

 heavier by combustion. Tin, lead, and other metals, burn when 

 heated to redness; and the residuum, or result of combustion, is 

 heavier than the metal they set out with. Combustion, there- 

 fore, said they, consists not in the separation of phlogiston, 

 but in the fixation of air, and substances refuse to burn when air 

 is excluded, 



Mr, Brande illustrated these positions by many of the original 

 and curious experiments detailed in Mayow's treatise on the ni- 

 tro-uric spirit. In speaking of Rey's publication, the Professor 

 observed that its present scarcity was enigmatical, it having been 

 reprinted at Paris in 1777; but it contained many doctrines to 

 which the new French tbcorists have laid claim, as he should 

 prove in detailing the history of the antiphlogistic theory, v.'hen 

 the neglected merits of Rey and Mayow would again call for at- 

 tention. 



Having paid a just tribute of praise to the labours of Hales 

 and Boerhaave, the founders of pneumatic chemistry, Mr. Brande 

 gave an account of the invention of the thermometer, an instru- 

 ment which tended materially to the progress of that difficult 

 anf\ refined branch of chemistry, relating to the nature and pro- 

 perties of heat. Santorio was 'the first who constructed the ait 

 thermometer, which was much improved by Van Helmont. The 

 Florentine Academicians used smaller tube's filled with spirits of 

 wine; the iustniment was perfected by the dexterous ingenuity 

 of Falirenhcitj a i)uuluiipt merchant of Dantzie. 



TIi« 



