6 i 
of the Acid of Borax. 
The degree of heat in the sand was from 180° to 240*, by 
which the fluid evaporated very slowly. During this operation, 
there ascended, or rather crept up the sides of the retort, a con- 
siderable quantity of salt, in very loose flowers, rising pretty 
high above the fluid, increasing by degrees, and chiefly occupy- 
ing that half of the retort which received a greater degree of 
heat than the other ; but never the opposite or colder half. In 
four days, the fire being extinguished towards the evening of 
the last, the fluid had evaporated, so as to leave the salt appa- 
rently dry. After cooling for some time, the bladder upon the 
phial was moistened by water, and the vessels were separated ; 
the sealing-wax also having been removed, and the stopper taken 
out, the distilled fluid was poured back, through a glass fun- 
nel, upon the salt, without disturbing the lute. 
Exp. vi. As soon as the fluid was added, the salt at the 
bottom began by degrees to dissolve : that on the sides of the 
retort did the same, after it was heated, but soon began to 
form again : the solution appeared of a yellowish hue. In 
general, however, the whole experiment took the same course 
as in Exp. v. and the smell, both of the salt and the fluid, 
seemed to be unchanged. The only difference was, that the 
former did not appear like salt, (the crystallization on the sides 
excepted, ) and in single detached crystals, but something like 
a white, uniform, spongy, and, as it were, earthy mass. The 
fluid was now again taken from the phial, as in Exp. v. and 
poured back upon the salt. 
Exp. vii. yin. and ix. During the third distillation, bright 
small part of the salt (and a larger as the cold increased) precipitated, which was 
dissolved again, by a fresh application of heat. But, with the degree of heat I em- 
ployed, no more than one part of salt would dissolve in six parts of the acid. 
