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XIII. On the late extraordinary depression of the Barometer. By 
Luke Howard, Esq. F. R. S. 
Read January 24, 1822. 
The quicksilver having fallen to a lower point in the baro- 
meter in the course of last month than any person, probably, 
remembers to have seen it at, in the neighbourhood of Lon- 
don, a short account of the circumstances may, perhaps, not 
be unacceptable to the Royal Society. 
On the evening of December 24, I found the barometer at 
28.20 in. the wind being moderate at S. E., with steady rain, 
the temp, without, at 8 p. m. 45 0 . Water boiled freely at 
210°. Finding the depression still to continue, I took a por- 
table barometer, on Sir H. Englefield's construction, and 
having ascertained its height to be, at 11 p. m., 27.96 in., I 
set it up in my chamber on the first floor. At 5 a. m. the 
25th, this instrument gave 27.83 in., and I have reason to 
think it did not go much lower : the rain had ceased early in 
the night, and it had become somewhat star-light, with a 
calm air, and hazy cirrostrati above : soon after five, how- 
ever, the wind rose again, bringing some rain, apparently 
from N. W., but there was no tempest that I had opportunity 
to observe, though it might have blown hard during the few 
hours I slept. The pencil of my clock barometer travelled 
precisely to two-tenths below the bottom of the scale, having 
made a continuous downward sweep of nearly an inch and 
four-tenths in 24 hours : it appears to have turned to rise 
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