286 Tramhition o/' Rev's Essai/s. 



were lost, their weights would nevertheless greatly diminish, 

 not so much when examined by reason, as by the balance. 

 Such are the Indian metal called calaem*, and some kind of 

 saffron of Mars, as the chemists observe. 



Essay XXVIII. 

 If Lead increase in weight like Tin. 

 I should have made an end, but the Sieur Brun writes to me, 

 that having observed the increase of the tin, he made the same 

 experiment on lead, which he found lost an ounce in the pound ; 

 which plunged him further in doubt, expecting to have found 

 the same increase as in the tin, from the similarity of their 

 nature, and having been calcined by the same process. But 

 to the Sieur Brun's experiment, I oppose those of Cardan, Sca- 

 liger, and especially Ctesalpin, already brought forward, who 

 says that it is worthy of admiration, that common lead when 

 calcined, increases in weight eight or ten pounds per cent. 

 Shall I array these persons in the debate, each in support of 

 his own experiment? I am too peaceable — I reconcile them 

 thus. One kind of lead is purer than another, whether from its 

 coming from different mines, or from its having been melted 

 before. The above named found an increase with the purest; 

 the Sieur Brun a loss in the other. 



Conclusion. 

 Behold, now the truth, whose brilliancy dazzles your eyes, 

 which I have dragged from the deepest dungeons of obscurity, 

 whose approach has hitherto been inaccessible. It is she who 

 has made all the learned men sweat with vexation, who, de- 

 sirous of becoming acquainted with her, have been compelled to 

 leap over the difficulties that surrounded her. Cardan, Sca- 

 liger, Fuchsius, Csesalpin, Libavius have sought her curiously, 

 but never found her. Others may seek her in vain, if they 

 follow not the road which I have first cleared for them, and 

 made royal ; all the rest being only thorny paths, and inextri- 

 cable labyrinths that never lead to an end. The labour has 

 been mine — to the reader be the profit of it, to God only the 



glory. — END. 



* Zinc. 



