^ 



Ohfcr Nations upon the art of\ ^r. toy 



pin's head, nibbed on fmootlipa^:>cr, would exKibk a luminous 



appearance in the dark. 



We'are forry, that the quantity brqilgbt was not /iifficient 

 to be fubje6led to proceffes for afcertairiing its component 



parts.*'' May they not be a calcareous earth, for the hafis/and 

 vitriolic acid, united with phlogifton, into a highly inflamma- 

 ble' fulphur? ' r •: , ". ' J -- J a 



. - K . 



Should the vitriolic acid b e ' pf dcur abl e from this fubftance 

 it might well pay the refparches of thofe, who fliall effed th 

 difcovery of its T)cd. " 



V 



""" Happy, if I can, by any means,>oT\clv\ce to the adv 

 ment of American fcience, 



w\ 



I am, with the greateil refpe^, Sir 





*t 



« ' 



Your mofl obedient humble fer\^ 



tL^'i^/, > . ^-^^ - * SOLOMON DROWN. 



i?^i;r ;s: WlU'iamu L, Z. Z). -^ ' ^ ^^- - . .i £ r 



I' - 





WlT * - - * ,,'.-—-- 







Vb/crvatlons upon We art ofextraElmg Marine Salt from fea wafer, 

 by evaporation, produced by the fun's heat ; 'whh a^ defcjlption of 



"- "T 



the works, and the ftveral procejfa ifcd in preparing Medmnal 

 Salts, and Magne/.a All>a. By JA^IES THACHER, MM- 



■1 r+-" 



■ Every effky having in view the advancement of our 

 manufaaories, and aicouragmg the efforts qfinauftrf^wm; it 



is prefumed, receive the approbation, of ertry. daft and de- 



, fcii^ition 



« 



\ 



