xc 
General Results or the Makeestoun Observations. 
1 
Table 82. — Diurnal Variation of the Relative Humidity of the Air, for each Astronomical Season 
and for the Year, deduced from the Observations of the Years 1843-6. 
aiak. 
Nov. 
Feb. 
May. 
Aug. 
Mak. 
Nov. 
Feb. 
May. 
Aue. 
Mean 
Dec. 
March. 
June. 
Sept. 
Year. 
Jlean 
Dec. 
March. 
June. 
Sept. 
Year. 
Time. 
.Jan. 
April. 
July. 
Oct. 
Time. 
Jan. 

April. 

July. 

Oct. 

h. III. 
J Z 1 u 

1 n fi 1 ^ 
-r u • u i «> 
+ 
0-061 
+ 
0^103 
+ 0 
062 
h. 
0 
m. 
10 
— 0-035 
— 0-090 
— 0^109 
, 
— 0. 1 OR 
yj' i yjo 

u-uoo 
1 Q in 
_i_ n 1 J 
+ 
•065 
+ 
• 105 
+ 
065 
1 
10 
— -043 
— • 1 07 
— .118 
— -uy / 
1/1 in 
_L. n 1 0 
+ 
•069 
+ 
•105 
4- .079 
"T •U / ^ 
I 
T 
2 
10 
— .044 
•V/ Jirt 
— -110 
— .119 
— • 1 -J U 
— -uyy 
15 10 
+ -014 
+ 
•065 
+ 
•109 
+ ^078 
+ 
066 
3 
10 
- ^027 
- -106 
- -112 
- ^120 
- ^091 
16 10 
+ -017 
+ 
•064 
+ 
•101 
+ ^075 
+ 
064 
4 
10 
- ^009 
- ^090 
- -102 
- ^096 
- ^074 
17 10 
+ -018 
+ 
•066 
+ 
•087 
+ ^072 
+ 
061 
5 
10 
+ •OOl 
- -052 
- ^079 
- ^058 
- ^047 
18 10 j 
-)- -022 
+ 
•058 
+ 
•062 
+ ^064 
+ 
051 
6 
10 
+ •OOS 
- -027 
- •OSl 
- ^016 
- -023 
19 10 
+ -019 
+ 
•050 
+ 
•023 
+ -052 
+ 
•036 
7 
10 
+ •OOS 
+ -009 
- -012 
+ -018 
+ -004 
20 10 
+ -021 
+ 
•027 
•017 
+ •oig 
+ 
012 
8 
10 
+ ^007 
+ -028 
+ •OSl 
+ -038 
+ -026 
21 10 
+ -007 
•010 
•054 
- ^019 
019 
9 
10 
+ •oog 
+ -037 
+ ^059 
+ -051 
+ -039 
22 10 i 
- -005 
•054 
•077 
- ^057 
048 
10 
10 
+ -007 
+ •OSS 
+ '078 
+ -060 
+ ^049 
23 10 
- -027 
•073 
•103 
- ^085 
072 
11 
10 
+ -004 
+ ^060 
+ •OSS 
+ -057 
+ -052 
188. Diurnal Variation of the Relative Humidity. — The following are the approximate epochs of maxima 
and minima, as obtained from Table 82. 
Winter, Nov., Dec, Jan., Maximum 7^ a.m. Minimum 1^ SO™ p.m. 
Spring, March, April, May, 2>^ a.m l^^ 50^ p.m. 
Summer, June, July, Aug., S'* a.m l^^ 20m p.^. 
Autumn, Sept., Oct., Nov., 3li a.m 2^ 10°^ p.m. 
Year, 3'^ a.m 40™ p.m. 
The diurnal variation of relative humidity is nearly the inverse of that of the temperature of the air. 
The mean relative humidity occurs at 8'^ 33"" a.m., and at Y'^ 1™ p.m., theintei-val being lO'^ 28^. 
The range of the diurnal variation is least in winter, = 0-066 ; it is greatest in summer, = 0*227 ; the 
values of the range for spring being 0-179, and for autumn being 0-208. 
Atmospheric Pressure. 
189. The Mean Pressure of the Atmosphere at Makerstoun, 213 feet above the mean level of the sea, as 
deduced from the observations in the 8 years 1842-9, =29-615 inches of mercury at 32^ Fahrenheit, measured 
on brass at 62° Fahrenheit ; with a probable error of 0-009 inch, each year's mean recei\'ino- an equal weisrht. 
The mean pressure for any future year = 29-615 inches, with a probable error of 0-026 inch.* 
Table 83. — Monthly Means of the Atmospheric Pressure at Makerstoun, for the Years 1841-9. 
Month. 
1841. 
1842. 
1843. 
1844. 
1845. 
1846. 
1847. 
184S. 
1849. 
1 Mean of 
Heitrht of 
j 213 feet. 
8 Years. 
Mean 
Level 
of Sea. 
in. 
in. 
in. 
ill. 
1 in. 
in. 
Jan. 
29-584 
29^357 
29-'693 
29^512 
29^392 
29-604 
29-722 
29-508 
29-547 
29-7S6 
Feb. 
•611 
•499 
•321 
•704 
•617 
•625 
•194 
•819 
•549 
•7SS 
March 
-485 
•662 
•529 
•741 
•406 
•775 
•354 
•755 
•588 
■826 
April 
•946 
•487 
-805 
•642 
•535 
•455 
•595 
•450 
•614 
•S50 
May 
•626 
•620 
-980 
•703 
•648 
•599 
•770 
•796 
•718 
•951 
June 
•764 
•619 
•627 
■597 
•706 
•672 
•475 
•735 
•649 
•879 
July 
•665 
•635 
•625 
•622 
•556 
•794 
•619 
•583 
•637 
•865 
Aug. 
29-567 
•723 
•656 
•489 
•578 
•691 
•751 
•526 
•658 
•634 
•863 
Sept. 
•483 
•652 
•935 
•817 
•645 
•732 
•605 
•717 
■792 
•737 
•970 
Oct. 
-372 
•682 
•401 
•397 
•602 
•312 
•646 
•551 
•606 
•525 
-7oS 
Nov. 
•453 
•448 
•471 
•563 
•323 
•655 
•643 
•601 
•530 
•529 
•765 
Dec. 
•649 
•962 
•892 
•369 
•599 
•490 
•542 
723 
•653 
•892 
Mean 
•653 
•609 
•645 
•586 
•571 
•638 
•555 
•663 
•615 
•846 
* All the observations i\i-o roduooil to the m, mi of the lliut and crown yluss burouietor of the Koval Sociotv of London. In com- 
paring those results with others reduced to the llint-glnss baronietor only, a correction of -f- 0 003 in. should be applied. See Intro- 
duction 1844, page Iv. 
