PRESSURE OF AQUEOUS VAPOUR. 
271 
TABLE X.—Pressure of Aqueous Vapour, considered in relation to the Moon’s Age and Declination. 
Mean 
Pressure. 
No. of 
Daily 
Means. 
Mean 
Pressure. 
After 
Moon 
farthest 
North. 
D: 
No. of 
Daily 
Means. 
Mean 
Pressure. 
After 
Moon 
farthest 
North. 
Day. 
Mean 
Pressure. 
14 
ONIAMMBwWMOrH OF 
This Table has been formed from Table IX. in the manner already indicated, Table II. of the Abstracts 
of the Magnetical Observations, excepting that no means for the Sundays were employed. 
Pressure of Aqueous Vapour with reference to the Moon’s Age.—From the above, and the following means 
of groups, there seems to be a maximum of pressure about three days after the time of full moon, and a mini- 
mum about three days after the time of new moon. 
im. in. 
12 days till 18 eye, Full Moon, 0-296 a days till 3 Ene New Moon, 0-284 
NS pasar 22 OPS eee Ont cs 7 0-281 
1 ese 26 0-295 4 sande 1d gett 0-289 
DBA tariecs 29 0-292 cS) apBe 14... 0:290 
Pressure of Aqueous Vapour with reference to the Moon's Declination.—The means in the above Table 
seem very irregular, The projected quantities shew four maximum peaks, which occur at intervals of seven 
days, namely, on the 2d, 9th, 16th, and 28d days after the Moon has its greatest north declination ; but these 
may be at once traced to the less number of observations from which the means are deduced for these days, 
and this due to the want of means for the Boneei The means of groups are as follow :— 
Ee days till ~~ Moon farthest North, 0- 279 11 days till 17 a Moon farthest South, 0- 302 
Bish oe 0:273 ake Gat 20 0-298 
: ate te “A 0:279 TBMVe hy... 24 0-299 
ths aR. 13 0-298 21 bie. aS: 27 0°295 
These means shew the minimum about three days after the Moon has its greatest north declination, and 
the maximum about three days after it has its greatest south declination. 
Extreme Daily Mean Pressures of Aqueous Vapour and the Ranges. 
Jan. Feb. March. April. May. June, July. Aug. Sept. Oct. Nov. Dec. 
in. in. in. in. in. in. in. in. in. in. in. in. 
Greatest, 0-342 0-259 0-304 0-322 0-359 0-365 0-489 0-541 0-529 0-417 0-311 0-331 
Least, 0-154 0-107 0-157 0-150 0-217 0-253 0-308 0-320 0-229 0-167 0-174 0-191 
Range, 0-188 0-152 0-147 0-172 0-142 0-112 0-181 0-221 0-300 0-250 0-137 0-140 
The greatest daily mean in the year is that for August 17, being 0°541 in. 
Mb e eas tine tey: adnan vases Seber nipyeaedetaoleabieye February 18, beng. : 07107 ... 
The greatest range of the daily means in any month is that for September, being 0°300 ... 
Mihewlensiy Rass a3 nds’. Bits ttrcceh atone Gas abdwe oh MAM aatoamimebnatelaniaoes 8 June, being 0-112) 5. 
E 0-434 ... 
The range of the daily means for the whole year 1843, is 
