EXPERIMENTS on THE SWEET SPRINGS. 199 
the acidity of the water might not be owing to it; and 
alfo to determine the nature of the air, whether fixed or 
not. Having therefore caught a quantity of the air in a 
decanter, I communicated a part of it to an equal bulk of 
pure mountain water, and after agitating them for fome 
time, gave it to feveral to tafte; who agreed that it had 
the tafte of the fpring water. Upon a fecond trial this ex- 
periment did not fucceed, I had not an opportunity of 
trying the nature of the air by means of chalk-water, and 
was prevented from profecuting any farther enquiries into 
the nature of thefe celebrated waters by a fudden alarm, 
to which the frontiers were then continually expofed. 
Thefe waters have been falfely called /weet, for their 
tafte is evidently acidulous. The experiments alfo thew 
that they contain an acid. ‘Their tafte refembles exaCly 
that of waters artificially impregnated with fixed air, ex- 
tricated from chalk, by means of the vitriolic acid, and I 
conceive muft be nearly the fame with the true Pyrmont 
water. They have little or no fmell, do not form an in- 
cruftation, nor do they leave a depofit upon ftanding many 
hours. Upon bathing in the morning, the fkin has a 
foapy kind of feel. This was not obferved in the evening. 
There is near this {pring another, a very ftrong cha- 
lybeate. 
Iam, with great regard, yours, 
J. MADISON. 
N° XXIII 
A Letter from the Rev. JEREMY BELKNAP, on the 
preferving of Parfnips by drying. 
Dover, New-Hampfhire, March 5, 1784. 
SIR, 
Read Apr. MONG tthe number of efculent roots, the 
1 26, 1784. parfnip has two fingular good qualities. 
Cea One 
