282 
Abstracts of the Makeestgun Obseevations, 1843. 
The monthly means exceed the means of the highest and lowest readings in each month excepting May, 
the mean of the twelve monthly maxima and minima heing 0-118 in. less than the mean for the year. 
The monthly means exceed the means of the highest and lowest daily means in each month with the ex- 
ceptions of May and November ; the mean of the twelve monthly maxima and minima of daily means being 
0-069 in. less than the mean for the year.* 
TABLE XX.— Daily, Weekly, and Monthly Means of the Pressure of the Dry Air in 1843. 
Civil 
Day. 
J 
Jan. 
Feb. 
March. 
April. 
May. 
June. 
July. 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
in. 
1 
[ ] 
29-035 
29-468 
28-704 
29-920 
29-009 
29-184 
29-102 
29-576 
[29-353] 
29-322 
29-712 
2 
29-747 
28-910 
29-714 
[28-968] 
29-814 
28-700 
[29-159] 
28-854 
29-549 
29-400 
29-409 
29-640 
3 
29-710 
28-748 
29-849 
29-097 
29-436 
28-911 
29-067 
28-716 
[29-637] 
29-443 
29-126 
[29-577] 
4 
29-263 
29-296 
29-951 
28-906 
29-113 
[29-094] 
29-315 
28-773 
29-756 
29-371 
29-032 
29-624 
5 
29-440 
[29-359] 
[29-824] 
29-129 
29-045 
29-429 
28-987 
29-080 
29-808 
29-298 
[29-140] 
29-277 
6 
29-502 , 
29-678 
29-685 
29-049 
29-025 
29-392 
28-983 
[29-132] 
29-565 
28-787 
29-144 
29-583 
7 
29-072 
29-785 
29-781 
28-783 
[29-286] 
29-127 
29-195 
29-403 
29-676 
28-697 
28-982 
29-368 
8 
[28-917] 
29-738 
29-962 
28-904 
29-328 
28-515 
29-300 
29-340 
29-638 
[28-964] 
29-148 
29-607 
9 
28-763 
29-792 
29-914 
[29-224] 
29-478 
28-504 
[29-347] 
29-482 
29-543 
29-062 
29-411 
29-689 
10 
28-266 
29-800 
29-596 
29-528 
29-727 
29-107 
29-480 
29-565 
[29-574] 
29-262 
29-078 
[29-650] 
11 
28-458 
29-830 
29-589 
29-612 
29-711 
[29-175] 
29-648 
29-567 
29-319 
28-680 
29-557 
29-656 
12 
28-528 
[29-593] 
[29-413] 
29-465 
29-495 
29-687 
29-477 
29-569 
29-618 
28-858 
[29-543] 
29-820 
1 o 
97.890 
9Q.01 9 
29-141 
29-644 
29-410 
29-646 
29-1 12 
29-716 
29-757 
14 
28-233 
29-416 
28-995 
29-185 
[29-320] 
29-596 
29-412 
29-492 
29-403 
29-360 
29-883 
29-657 
15 
[28-847] 
29-117 
29-373 
29-463 
29-101 
29-621 
29-341 
29-372 
29-309 
[29-223] 
29-612 
29-562 
16 
29-261 
28-972 
29-497 
[29-423] 
29-103 
29-583 
[29-303] 
29-357 
29-363 
29-201 
29-588 
29-S37 
17 
29-548 
29-277 
29-236 
29-487 
29-369 
29-557 
29-440 
29-349 
[29-429] 
29-164 
29-111 
[29-754] 
18 
29-692 
29-443 
29-368 
29-511 
29-602 
[29-544] 
29-105 
29-374 
29-390 
29-644 
28-858 
29-902 
19 
29-875 
[29-174] 
[29-198] 
29-362 
29-639 
29-536 
29-109 
29-150 
29-702 
29-928 
[28-983] 
29-S74 
20 
29-776 
29-160 
29-301 
29-248 
29-489 
29-588 
28-975 
[29-136] 
29-406 
29-518 
28-S48 
29-694 
21 
29-556 
29-107 
28-925 
29-241 
[29-417] 
29-377 
29-023 
29-268 
29-532 
29-331 
2S-771 
29-776 
22 
29-475] 
29-082 
28-859 
29-233 
29-251 
29-490 
28-965 
28-747 
29-882 
[29-319] 
28-724 
29-476 
23 
29-292 
29-167 
28-947 
[29-230] 
29-277 
29-492 
[29-226] 
28-931 
29-943 
29-214 
28-970 
29-611 
24 
29-084 
29-328 
29-333 
29-537 
29-243 
29-514 
29-485 
29-167 
[29-703] 
29-002 
29-157 
[29-720; 
25 
29-265 
29-374 
29-637 
29-031 
28-989 
[29-419] 
29-559 
29-137 
29-818 
28-921 
29-209 
29-S05 
26 
29-353 
[29-203] 
[29-463] 
29-091 
28-884 
29-420 
29-350 
29-236 
29-671 
29-078 
[29-201]' 29-S0S 
27 
29-030 
28-846^ 
29-618 
29-345 
28-813 
29-331 
29-368 
[29-270] 
29-372 
29-095 
28-776 
29-S42 
28 
29-036 
29-034 
29-600 
29126 
[29-149] 
24-269 
29-293 
29-107 
29-405 
28-322 
29-348 
29-S99 
29 
[29-081] 
29-646 
29-304 
29-469 
29-227 
28-838 
29-357 
29-417 
[2S-990] 
29-747 
29-7S7 
30 
29-001 
29-212 
[29-491] 
29-499 
29-172 
[29-109] 
29-611 
29-082 
29-058 
29-626 
29-511 
31 
29030 
28-764 
29-238 
29-199 
29-566 
29-063 
[29-463] 
J Mean 
29-138 
29-314 
29-438 
29-235 
29-341 
29-300 
29-250 
29-247 
29-553 
29-149 
29-237 
29-683 
This Table has been formed by subtracting Table IX. from Table XV. 
Annual Variation of the Pressure of Dry Air. — The pressure of the dry air is least in January, being 
29-138 in. ; it increases from thence till March, then diminishes in April ; after a slight increase in May it 
diminishes till August, the pressure being nearly the same in that month as in April ; it then increases con- 
siderably in September, and diminishes to a greater extent in October and November ; the greatest pressure 
occurs in December, being 29-683 in. The range of the monthly means is therefore 0-545 in. If the pressure 
in December be kept out of view, the annual variation for 1843 indicates maxima in the equinoctial months, 
and minima near the solstices. The following are the means for the three different groups, namely. 
* I have pointed out elsewhere (Transactions of Sections. Report of Brit. Assoc. 1845. p. 15), that the means of the nionthlv 
maxima and minima are probably always less than the mean pressure in certain latitudes (including 50° and ti0 c north), but that in 
other latitudes the reverse is the case. The explanation of this fact will probably be found in the prevalence and excessive pressures 
of particular winds. 
