The Sun.
London, England, 1848-11-02 00:00:00

THE MEAN TEMPERATURE OF THE DEW POINT AT

GREENWICH
For the month of April was 54 deg. 6 min., which is
3 deg. 0 min., 1 deg. 4 min., 0 deg. 2 min., 1 deg. 9 min.,
and 1 deg. 8 min. below those for the years 1841, 1842,
1845, 1846, and 1847 respectively; 1 deg. 7 min. and
0 deg. 1 min. above those for the years 1843 and 1844
respectively, or it is 0 deg. 9 min. above the average of
these seven years.
For the month of August was 52 deg. 8 min., which
is 2 deg. 2 min., 6 deg. 1 min., 5 deg. 0 min., 4 deg. 7
min., and 3 deg. 3 min. below those for the years 1841,
1842, 1843, 1846, and 1847 respectively, 0 deg. 5 min.
and 0 deg. 2 min. above those for the years 1844 and
1845, or it is 2 deg. 9 min. below tho average for these
seven years.
For the month of September was 50 deg. 9 min.,
which is 2 deg. 8 min., 2 deg. 6 min., 4 deg. 0 min. 2
deg. 3 min., and 4 deg. 0 min, below those for the years
1841, 1842, 1843, 1844, and 1846 respectively, 1 deg. 2
min. above those of the years 1845-and 1847, or it is 1
deg. 9 min. below the average of these seven years.
The mean value for the quarter was 52 deg. 8 min.,
which is 1 deg. 3 min. below the average for the corres-
ponding period of the preceding seven years.
The mean weight of water in a cubic foot of air for the
quarter was 4.5 grains, which: is, 0.2 less than. the
average for the seven preceding years.
The additional weight of water required to saturate a
cubic foot of air was 1.1 grain. The average value for
the seven preceding years was 1.0 grain.
The mean degree of humidity of the atmosphere for

July was 0.726:f0r August was 0.797, and for' Septem•
ber was 0.795. The avet ages for the seven preceding
years were 0.780, 0.804, and 0.842 respectively. The
value for the quarter was 0.785, which is 0.024 less than
he average for these years.
The mean elastic force of vapour for the quarter was
0.411 inch, which is 0.026 less than the average for
these years.
The mean reading of the barometer at Greenwich for
July was 29.836 inches, for August was 29.732 inches,
and for September was 29,832 inches; these values are
0.041 inch above, 0,065 inch below, and. 0,021 inch
above, respectively, the averages for the seven preceding
years. The mean value for the quarter was 27.797
inches, which is of the same value as the average for the
seven preceding years.
The average weight of -a cubic foot of air under the
average temperature, humidity, and pressure, was 527
grains; the average for the seven preceding years was
526 grains.
The rain fallen at Greenwich in July was 2.1 inches,
in August was 4.6 inches, and in September was 2.4
inches. The average amount for the seven preceding
years was 2.3 inches in July, 2.7 inches in August, and
2.2 inches in September. The amount fallen in the
quarter was 9.1 inches, which is 1.9 inches greater than
the average for the seven preceding years. The average
fall of rain during this quarter, as derived from the ob-
servations since the year 1815, is seven inches. In the
year 1824 the fall of rain in the quarter ending Sep-
tember 30 was 9 inches; in 1828 it was 12.5 inches; in
1829 it was 11 inches; and in 1839 it was 10. b
inches. The total amount of rain fallen this year till
Sept. 30, was 24 3 inches, in 1841 it was 21.2 inches, in
1842 it was 14.2 inches, in 1843 it was 17.5 inches, in
1844 it was 16.2 inches, i❑ 1845 it was 16.6 inches, in
1816 it was 17.5 inch, s, and in 1847 it was 11.6 inches;
so that the fall of rain this year exceeds that in 1841 by
2.7 inches, in 1842 by 9.7 inchea, in 1843 by 6.4 inches,
in 1844 by 7.7 inches, in 1845 by 7.3 inches, in 1846 by
6.4 inches, and in 1847 by 12.3 inches. The excess of
the fall of rain this year over the average for the seven
preceding years is 7.5 inches.
In the years 1824 and 1828 the depth of rain fallen to
the end of September exceeded 23 inches; and in the
years 1829 and 1839 the amount collected exceeded 20
inches. So large a fa'l as 24.3 inches within the first
nine mouths of the year has probably not been exceeded
within this century.
The temperature of the water of the Thames was 63
deg. 0 min. by day, and 62 deg. by night. The water,
on an average, was 3 deg. 9 min. warmer than the air.
The horizontal movement of the air was about 130
miles daily; during the period of time between July 19
and July 27, it amounted to 233 miles per day; from
July 31 to August 6, its average daily value was 240
miles, and on August 21 it exceeded 300 miles.
The highest and lowest readings of the thermometer
in air at the height of four feet above the ground, and
protected as much as pozsible from the effects of radiation
and rain, were 85 deg. 3 min. and 32 deg. 8 min.
The average daily ranges of the readings of the ther-
mometer in the atr, at the height of four feet were 22
deg. 5 miu. in July, 18 deg. 5 min. in August, and 20
deg. 9 min. in September. The average ranges for these
months, from the observations of the seven preceding
years, were 17 deg. 2 min., 17 deg. 1 min., and 16 deg.
2 thin. respectively.

In July the readings of the thermometer on grass
were 29 deg. 5 min. on one night, between 32 deg. and
40 deg. on nine nights, between 40 deg. and 50 deg. on
twelve nights, and above 50 deg. on nine nights. In
August the lowest reading was 36 deg. ; and the readings
we re below 40 deg. on four nights, between 40 deg. and
50 deg. on eighteen nights, and above 50 deg. on nine
night,. In September, the readings were below 32 deg.
on nine nights, and the lowest was 23 deg. ; they were
between 32 deg. and 40 deg. on seven nights, between 40
deg. and 50 deg. on nine nights, and above 50 deg. on
four nights.
The observer, at Uckfield, says—" That there was a
severe white frost on the morning of August 10. with
ice on the brooks and low grounds."
The mean amount of cloud fur July was 6.6, for Au•
gust was 7.6, and for September was 5,6. The average
values for the seven preceding yea:s were 6 7, 6.3, and
6.0 respectively.
There were five exhibitions of the aurora borealis
during the quarter, which occurred on July 11, August
28, S. ptember 4,8, and 18.
Thunder storms at different parts of the country oc-
curred on July 14, 26, August 1,3, 4,5, 6,7, 8,9, 10,
11, 22, 23, 31, and September 5; and lightning, unac-
companied by thunder, was seen on July 24, August 23,
24, 25, September 22 and 25. The storms of July 14
were observed at Greenwich, Latimer Rectory, Car-
dinton, Saffron Walden, and Leicester. At Greenwich,
thunder clouds were observed first in the W. and N.W.
at Bh. 30w. P.M., and from this time till near midnight
the thunder followed the lightning at intervals varying
from 5 413 C. to 40 sec., and lightning was visible during the
whole of the night. At Latimer the storm is described
as awful, and of five hours' duration. On July 24 light-
ningstoarth
tmwsas seen at Saffron Walden; on July 2t; there was a
heard
dder storm at Leicester; on August 1, thunder was
ha4:id
I,aliegehnawn Greenwich during the afternoon ; on Aug. 3 and
Saffron Walden; on August 5, there were thunder
was strautekGbryeetnhweiefihg,
were thunder storms lightning.
ntoi
Leicester; S
loa ffnr oAonnu:VAuasultgdu6e `Malden,
at,
nLBd,e
7iactc there
Ls .eeir.,
ar the last-mentioned place a tree
no
oster
lightninganel at
was Exeter;
seen
nAAu
August
t9,10a
at t Greenwich,Stone;
on Abuu-t
Au-
gust 11, at Greenwich, between the hours of 6 P.m. and
8 P. sr., the storm began in the E and many of the flashes
of lightning
were vivid, and preceded' by the thunder two
V.* 41. i, 2. ..- •