136 ANDREAS KURTZ 



borax." Kurtz does not appear to have had 

 anything to do with the purifying of "tincal." 

 He manufactured borax from boracic acid 

 and soda,the process invented by Payen and 

 Cartier in 1818, and we believe we are 

 perfectly correct in saying he was the first in 

 this country to make, by this process, the 

 exquisite article which he introduced. Before 

 his day, the borax of commerce was very 

 inferior stuff. 



In his "Laboratory Book" there are very 

 numerous observations, fully and carefully 

 recorded, on his experiments in the manufac- 

 ture of borax. 



It is headed : "Borax Operation," and the 

 date is March i, 1832. 



First there are tests of boracic acid and 

 borax, then notices of soda : "the caustic soda 

 of Mr. E. P. Thompson is 40 sp. gr. 



" Muspratt's alkali contient 70 dry carbonate 

 of soda, 12 muriate and 18 sulphate." 



"The pearlash of Lutwych, 5 of it precipi- 

 tated by 1 5 of tartaric acid produces 1 1 */ of 

 supertartarate of potassa. 



Then comes the account of mixings. 



"When boracic acid is saturated with 

 caustic soda, all crystals of borate of soda are 

 soft and of a form like 'Tincal'" 



