t J 4 r ] 
elapfed from the time, when a brifk effervefcence, 
accompanied with weak nitrous fumes, arofe, until 
the liquor became a confident mafs, and fparks of 
fire ifiued from the coils of tin ; which having 
attrafled part of the folution above the common 
level, brought it into the condition in which it is 
readily dried, heated, and fired. 
A like quantity of the fame folution, kept in a 
ftrong boiling heat, does not acquire fuch con- 
fidence in a ten-fold fpace of time. 
The hafty exhalation, therefore, is not caufed: 
by the heat alone ; neither does it feem to require 
any great furface. What elfe it is owing to, I 
commit for a while to the examination of the cu- 
rious. 
Orchard- Street, Portman- ty tj* p 
Square,. Dec. 23, 177 
Received 
