the Trigonometrical Station on Rumbles Moor, Yorkshire. 135 
moreover, the advantage of noting the thermometer at the base 
as well as at the summit of the mountain where the observations 
are made, and of rudely determining their difference of altitude 
by the barometer. 
(Height of Eye, 44 feet.) 
At Rumbles Moor, April 30th, 
h m. Therm, 
14 30 observatory depr... 53 37 34 
15 20 ae ae 53 25 53! 
15 40 + 56 53 10 535 
16 30 ays ats Ba! a 51 
1770 ae wee Be 'S 504 
17 30 Se ave 52 54 49 
1s 0 2% ee 52 35 47 
18 30 BA 3% yas 45 
At Rumbles Moor, June \9th. 
13 20 observatory depr. 53 14 48t 
14 30 a ge 53 13 4gt 
17 20 ee ie 58.13. 492 
18 40 a su 53. 4 474 
The mean of the observations in 1821 was 53.0, 
At the Observatory, March 30, 1821. Rumbles Moor 
elevated. 
Hour. Barometer. Wind. Angle of Elevation. Therm. Therm. at 
eich../ m0. eet) Moor. 
10 29°52 S.W. 42 6 44 39 
10 30 ee oe 42 5 43 4] 
1.0 an es 42 4 46 40 
11 30 2 ee 42 4 47 413 
12 0 29°33 42 3 48 41 
12 30 °° “0 42 3 47 39 
13. 0 oe ee 42 1 47 43 
13 30 os oe 42 2 49 Al 
14 0 29°32 oe 42 2 50 4 
15 .0 ee oe 42 4 50 43 
15 30 oe ee 42 4 49 41t 
16 0 os oe 42 1] 49 Al 
17 0 ee oe 42 9 49 41 
17 30 ee Seiad 42 10 48 , 39 
18 0 29:26 S.W. ee 46 36 
The mean of the extremes is about 42’ 6” and the mean dif- 
ference of the temperature of the stations 7°, that of the Moor 
being the lowest. The temperature of the vapour by Daniell’s 
hygrometer was 8° minus that of the atmosphere, , . be 
L 
