[ 426 j 
Account of the firft Observations made on the 
going of this Hygrometer. 
ftead June 10 , 54. My firft hygrometer was ready for 
1 77 3 * oblervation at the beginning of la ft Fe- 
bruary ( 1 772), in a rainy feafon, A few hours after 
it was taken out of melting ice it was already at 54 
degrees of its fcale. The next morning it was only 
at 50, but towards noon it rofe again to 54. I car- 
ried it down to my cellar, which being a confiderable 
depth under ground is commonly very damp. As l 
went down the flairs, I perceived that my hygro- 
meter continued falling, fothat when I hung it up in 
the cellar it was as low as 35. 
55. In the evening of the fame day it was at 284, 
and the next night at 214. It continued falling im- 
perceptibly during the reft of this month, throughout 
the whole of the next, and till the 1 9th of April. On 
that day it was at 3 2., and confequently very near ex- 
treme humidity : but in this interval it had very often 
rained, and fnowed, and even when the iky was clear 
over head, the ftreets had always remained wet, lo 
that it was evident from all the common appear- 
ances, that the humidity had gone on confiderably 
increafing in the cellar: 
56. i was impatient to fee the hygrometer rife 
again in the cellar itfelf, which I could not however 
expedl but w ith a north wind. At length, on the 
20th of April, though the rain ftill continued, the hy- 
grometer rofe half a degree. In the night of the 
20th to the 2 1 ft the wind came about to the north, 
and when I looked at my hygrometer in the morn- 
ing, I found it at 61. It continued rifing imper- 
ceptibly 
