?(    60    )
Among the jail populations-total average strength 17,021-there were
altogether 131 admissions and 41 deaths from cholera, giving a death-rate of
2·41 per mille of strength. Of the 49 jails in the province, 22 returned cholera
in 1871. The strength of the 22 affected jails is 10,170, the percentage of
admissions to strength 1·29, and of deaths to admissions 31. Of the 131
admissions there were 5 in January, 12 in February, 12 in March, 17 in April,
13 in May, 5 in June, 8 in July, 5 in August, 7 in September, 15 in October,
24 in November, and 8 in December.
Compared with the corresponding returns for the preceding year, the
figures for 1871 show a very marked decline in the prevalence of cholera
among the troops and jails of this province. This is in exact accordance with
the triennial cycle of cholera prevalence already alluded to in a previous
passage. The year 1871 is the third or " minimum of prevalence " year of the
sixth triennial period of the series we have given statistics for from 1854
to 1871, inclusive.
Meteorology.-The following brief sketch of the chief meteorological
characteristics of the year 1871 are from the admirable Report of Mr. H. F.
Blanford, Meteorological Reporter to the Government.
Atmospheric Pressure-Was above the average during January and
February at all stations except Darjeeling, and during March at all except
Darjeeling, Chittagong, and Monghyr. In April it remained lower at Hazari-
bagh, and to a less degree at Kattak, Calcutta, Dhaka, and Patna, but was
relatively higher than the average at Darjeeling, Chittagong, Monghyr, Jaisur,
and especially so at Berhampur. In May it was generally above the average,
and most so at Berhampur and Monghyr. In June it continued higher at
Berhampur, Monghyr, and Darjeeling, but fell everywhere else, and was
especially low at Kattak and Dhaka. During the south-western monsoon it was
above the mean at Chittagong, Dhaka, Jaisur, Monghyr, Darjiling, and
except during the month of July at Barhampur also. In October and
November the pressure was everywhere below the mean, and in December
also, except at Kattak and Patna.
Temperature of the Air.-In January  1871   the  mean temperature of
the  delta was a little below the average of the four years, the greatest depres-
sion being at Jaisur.    It was also below the same average at Kattak.    On the
other  hand,  on  both  coasts  of the  Bay  and in Bihar the temperature was
somewhat higher than the average.    In February the temperature was  above
the  mean everywhere.    The  greatest  success was at Barhampur, and at this
place, Dhaka, Hazaribagh, and Patna it exceeded  2°.    In March and April
the temperature again fell gradually below the average; first in the delta and
lower part of the Gangetic plain, and afterwards more generally, Patna, Hazari-
bagh, and the stations on the east side of the Bay being the last to remain
above the mean.    In May, owing doubtless to the early commencement of the
rains, the depression of temperature below the average was universal, amount-
ing to between 3° and 4°  at Kattak,  Jaisur, Hazaribagh,  Barhampur, and
Monghyr.    All the stations enumerated, except Patna, and temporarily one or
two other stations, continued to enjoy a temperature below the average up to
the end of the rains.    In October, however, the fall of temperature was less
than usual, and  November and December were warmer than usual at nearly
all the stations enumerated, especially at Kattak and  Patna.   Temperature of
the  solar  radiation as  compared  with the  preceding year,  for which alone
complete observations are available,  the  temperature  of solar radiation was
generally  greater in  January  and February 1871, and generally less in May,
in June, and more or less  throughout the  rains,   it was less at places lying
south of the latitude of Calcutta, and greater at places to the north.
Humidity.-The deviations of the humidity of each month of 1871 from
the average at different stations appear to have been very irregular. The
humidity was exceptionally high at Patna during the first five months of the
year, equal to it in July and August, and below the average during the last
four months. It was generally a little above the average in February, except
at Dhaka and stations on the coast line. In March this was the case only in
the delta and lower Gangetic plain. In April this excess increased, and in
May and June was very general. During the rains the difference became less,
and in October the humidity was generally at or a little below the average.