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British. Association for the Advancement of Science. 109 
readings were made every week, and corrected for the tempera- 
ture of the stem and scale, and the results were projected in the 
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form of curves. Among other valuable results, it is deduced ~ 
from the observations of 1838, that the oscillations of annual 
temperature would be virtually extinguished at a depth of 49 
’ feet in traf tufa, 62 feet in incoherent sand, or 91 feet in . 
sandstone. 
Mr. Snow Harris reported on the progress of the meteorol 
es * observations made by order of the Association at Pigmoth wth 
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the barometer and thermometer. The following general results_ 
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were mentioned. The mean height of the barometer at the Ply- ~ * 
~ .mouth dock-yard, 60 feet above sea level, at 60° F. was from aa ws 
latest results, 29.8967 in. It occurred in the mean .* 
gression four times in the day, viz. at 2h. 20m. and Sh. 10m. 
A. M.; and at 12h. 30m. and 6h. 15m. P. M., at which times the | 
Waves crossed the mean pressure line. The hours of greatest 
pressure were 10 A. M. and 9 P. M.—of least pressure, 5 A. M. 
and 3 P.M. With reference to the inflwence of the moon on the 
barometer, Mr. H. had reduced about 4000 of the observations, 
so as to show the pressure for the time of the moon’s southing, i 
and for each hour. before and after; but he could not discover — 
any differences which could be supposed to arise from ss 
influence. ~ 
Dr. Andrew Ure described a new Calaritheter, by hich the 
heat disengaged in combustion may be exactly measured, and he 
gave, also, some introductory remarks on the nature of different 
coals. In these researches, which are still in progress, the first. “ge 
determination sought is the proportion of volatile and fixed mat- ~~ 
ter afforded by any kind of fuel. This shows how far the coal . 
is a flaming or gas coal, and what quantity of coke it can pro- _ 
duce. The second point to be determined is the amount of sul-_ 
phur contained in the coals, a matter of great importance, as as Te- 
gards their domestic use, their employment by the iron master . 
and the manufacturer of gas. _Dr. Ure’s future researches are in- 
tended to embrace every variety of fuel, pet the results will 
doubtless be highly important. 
Prof. Stevelly corminailibatod bis method of filling a tatomeer 2 
without the aid of an air-pump ; and of obtaining an invariable 
level of the surface of the mercury in the cistern. He heated 
the mercury as hot as it could be used, and filled the tube in the 
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