271 
METEOROLOGICAL REPORT. 
Sydney, Month of April, 1858. 
From observations taken at 9 a.m. and 9 p.m m each day. 
CO 
*o 
d 
Temperature of Air. 
Moisture. 
Cloud, 
Winds. 
Remarks 
on 
Weather, etc. 
-a 
CJ 
rt 
is 
o s 
ci 
e>K 
Mean of 
9 a.m. 
and 9 pm. 
Maximum. 
Minimum. 
6 
to 
a 
rt 
** 
1—4 
Dew point. 
Rain. 
Inches. 
a 
Vi 
'p! 
53 
C (1 
| Extent. , 
Form. 
General 
Direction 
1 
30044 
66-6 
79'6 
54-8 
24-8 
63-5 
•0 
116 
5 
St. 
NE. 
Mist. 
2 
29-952 
66‘3 
810 
53.3 
27’7 
621 
•0 
115 
0 
S«utk.NE. 
Very fine. 
3 
30-0S8 
67-9 
76-6 
56-3 
20-3 
61-5 
•0 
in 
6 
Cu. 
SE. 
| Fine, but cloudy. 
4S 
•122 
69'4 
75-2 
600 
152 
62-7 
•o 
101 
8 
Cu.-Cu.-St. 
SE. 
5 
■027 
68-0 
77-8 
645 
•21 
111 
6 
Cu.-Cu.-St. 
NE. 
Thundercloud to East. 
6 
29.945 
63-4 
69-8 
6i-6 
S-2 
57-4 
•09 
90 
7 
Cu. 
SE. 
7 
•890 
63-5 
74-0 
48-5 
25-5 
57-3 
.0 
103 
1 
Ci.-St. 
SSW.NE. 
1 Atmosphere drv and 
8 
•893 
60-9 
77-9 
47-2 
30-7 
48-4 
•0 
116 
0 
\t.s\y. 
f brilliantly clear. 
9 
30-160 
63-9 
702 
47'6 
22-6 
49-0 
•0 
103 
0 
S8E. 
Sudden shower. 
10 
•245 
60-4 
68-7 
53-6 
151 
51-0 
•09 
93 
6 
Cu.-Ci.-St. 
SE. 
ns 
■089 
67-0 
74-8 
4S-7 
25-1 
590 
•o 
105 
8 
Ci.-St. 
NE. 
I Fine, calm, & agree- 
12 
•103 
68-6 
73-8 
58*3 
155 
56-7 
•o 
99 
4 
Cu.-Ci.-St. 
SE. 
j able weather. 
13 
•233 
62*2 
67-2 
58-6 
8-6 
56-9 
•96 
S4 
9 
Ni. 
SE. 
Heavv thunder sliwrs.* 
14 
•318 
64-S 
69-8 
5G-4 
13-4 
51-1 
•38 
92 
5 
Cu.-Ni. 
ESE. 
1- Showery cumuli. 
15 
•298 
60-2 
71-9 
56-4 
155 
57-7 
■36 
106 
5 
Cu.-Ni. 
East. 
16 
•370 
64-6 
73-7 
49-3 
24-4 
57-5 
0 
105 
5 
Cn.-Ci. 
ESE. 
j Fresh winds 
17 
•473 
65-3 
71-2 
61-1 
101 
55 -3 
•o 
89 
5 
Cu.-Ci.-St. 
SE. 
J Irregular clouds. 
18S 
•438 
640 
70-3 
57-1 
13-2 
56-2 
•88 
89 
9 
Cu.-Ni. 
SE. 
19 
•374 
61-9 
68-S 
54-3 
14-5 
58.0 
•03 
80 
9 
Cu.-Ei. 
South. 
( muli. 
20 
•286 
61-7 
65*^ 
56-1 
9-3 
59-3 
♦49 
88 
10 
Cu.-Ni. 
East. 
| Low and very threat- 
21 
•218 
61-3 
04 5| 
oG'7 
7'8 
59-1 
•59 
71 
10 
Cu.-Ni. 
NE. 
J ening clouds. 
22 
•178 
57*6 
70-8 
48-6 
22-2 
55-4 
•o 
101 
3 
Cu.-Ci. 
NE. 
) Calm and fine 
23 
■143 
55'G 
71-5 
47-7 
238 
53-9 
•0 
107 
0 
Cu.-St. 
NE. 
f Heavv night dew's. 
24 
•110 
61-1 
72-8 
48-0 
24'8 
59-2 
•03 
4 
Cu.-St.- 
NE. 
Thundercloud. 
25S 
•125 
62-0 
70-1 
48-3 
21-8 
53-8 
•0 
90 
3 
Cu. 
South. 
26 
■219 
59-7 
G9-0 
46-6 
224 
53-5 
•0 
2 
Cu. 
SW.SSE. 
j Detached clouds. 
27 
•186 
56-4 
73-3 
44-3 
29-0 
51-6 
•o 
108 
3 
Ci.-St. 
W.SW. 
) Calm and fine 
28 
•120 
59-3 
723 
46-3 
26-0 
543 
•0 
107 
1 
Ci. 
NNE. 
J Night dews. 
29 
•102 
60-0 
74-5 
533 
2l -9. 
54-2 
•03 
100 
5 
Cu.-Si.-Ni. 
SSE. 
30 
•315 
58-2 
61-3 
52-6 
8'7 
55-5 
■88 
71 
10 
Cu.-Ni. 
SE. 
Much rain. 
30-483 
70-9 
810 
36-7 
C5-1 
■96 
116 
10 
Hi 
gliest ) of s 
ingle readings. , 
29-882 
531 
... 
44 ; 3 
... 
45-4 
... 
71 
0 
Lowest J at 9 a.m. or 9 p.m,. 
30169 
62-6 
71-9 
52-8 
189 
56'6 
"5-02 
984 
5-0 
Means and sums 
April, 1858. 
1 
30165 | 
62-8 
73-6 
55-2 
18-4 
58-0 
536 
4-8 
Means and sums. April, 1856,1857. 
* April 13. These thundershowers occurred in a;very unusual manner, between midnight and 8 a.m. 
N.B.—The observations are not corrected for diurnal 
range The principal instruments have been compared 
at Greenwich, and the readings arc all reduced ac¬ 
cordingly. 
Pressure .—The barometer is 11 feet above the sea-level, 
The greatest range of pressure is *061 inches. 
The mean gaseous pressure of dry air is 29 - 7l0 
inches. The average weight of a cubic foot of atmos¬ 
pheric air is 533 grs. 
Temperature , — The mean of all self-registered 
maxima and minima is G2’4 degrees. The adopted 
mean temperature of the month is, therefore, 62.5 
degrees Fahrenheit, which is somewhat below 63*5. 
the corresponding mean of the two previous years. 
Moisture .—The dew-point is calculated from readings of 
Negretti’sand Zambra’s dry and wet bulb thermome¬ 
ters, by the use of Glaisher’s tables. 2nd Edn. 
The mean temperature of evaporation at 9 a.m. and 
9 p.m.,is 59'4 degrees. The mean elastic force of 
aqueous vapour is ‘459 inch. The average propor¬ 
tional humidity of the air is denoted by 83, per¬ 
fectly dry air being taken as 0, and saturated damp 
air as 100. 
Pain .—More or less rain fell on 13 days during the 
month. The total depth fallen is 5 02 inches. It is 
collected at one foot above the ground, and measured 
at 9 p.m. 
Sun’s heat is indicated for each day by the highest read¬ 
ing (self-registered) of a thermometer with a 
blackened bulb placed one inch above the surfaco of 
the ground. 
Cloud .—The extent of cloud is expressed by the tenths 
of the whole sky covered by it. 
The forms of clouds are denoted as follows, the num¬ 
ber of days on which each kind occurred being 
added in figures. 
Cu. Cumulus 19 Ci -Cu. Cirro-cumulus. ... 0 
Ci. Cirrus.4 Ci.-St. Cirro-stratus . 6 
St. Stratus...,,.1 Cu.-St. Cumulo-stratus ... 3 
Ni. Nimbus, ...9 
(N.B. The term Cirro-cumulus, I seldom, if ever, em¬ 
ploy, on account of the ambiguity and apparent unim¬ 
portance of what it generally denotes). 
Winds .—The winds may be thus summed up. 
9£ days. 
2 „ 
2 „ 
\rsw. 
2 
days. 
SE. 
SIT. 
4 
»> 
ESE 
ssw. 
4 
East 
South 
3 
NE 8 
SSE. 
14 
?» 
NNE 1 
W. S. JEVONS. 
Double Bay, near Sydney, N.S, W. 
