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and flowing westward, past Sylhet and Chuttuck, till it also suddenly adopts a southern turn to join the Brahmaputra and form the Megna. The Soorma valley, to the south of the Garo-Khasi-Jynteah Hills, is the high road to Cachar, and the stream affords good water carriage for the greater part of its length.
The Cbittagong rivers, including the Fenny, which separates it from Tipperah, fall into the east of the Bay of Bengal, but have no connection with the water system above described. The largest of them, the Kurnafoolee, on which Chittagong is situated, rises in the highlands to the north of the Blue Mountain, and gathers the contributions of the minor hill streams on either bank. Its course is south-westerly, as determined by the conformation of the hills, and changed perpetually by the protruding spurs.
On the western side of the Gangetic delta again the rivers have little or no connection with the main system of the country. The Damoodah, the Roopnarain, and the Cossye, may all be said to join the Hooghly between Calcutta and Saugor Island, but they are isolated rivers which have sprung from the plateau of Chota Nagpore, do not help to form the delta, and are independent entirely in character.
The Sooburnreeka, the Byturnee, and the Mahanuddy, have direction generally parallel to one another and a south-easterly course, the two former risiug in Chota Nagpore, the latter in the Central Provinces. The Mahanuddy is navigable for boats of a sort for 4(50 out of its 520 miles, and near Cuttack is about two miles in breadth in the rains.
Turning to the mountains and hills of the Lower Provinces,
in the small part of the Himalayan oan ID9' chain within the jurisdiction of the
Lieutenant-Governor, the elevations vary greatly, from Darjeeling 7,000 feet above the sea, on the south, to lofty Kinchinjinga, 28,000 feet high, on the north-west. Gneiss is the chief formation of the rock, while on the banks of the Runjeet river slate is found, and at the foot of the hills iron ore; moreover the presence of copper is ascertained.
The Rajmehal hills form the eastern projection of the Central Indian formation ending near the town of that name, round which the Ganges flows. They are the first connected high ground that strikes the eye of the traveller ascending the Ganges. South-west of these are broken, detached hills of considerable height, the largest of which is Parasnath, rising out of the surrounding country often in an almost perfect conical form to a height of about 4,400 feet. Many of these can be seen on the chord line between Haneegunge and Luckeeserai, and appear geographically as irregular links between the Rajmehal hills and the plateau of Chota Nagpore, which is hilly almost throughout, scantily populated, and covered with jungles over most of its surface. The extensive collieries at Raneegunge, on the confines of the Burdwan division and Chota Nagpore, furnish at present an unlimited supply of coal, which is of a moderately fair description. These regions where coal seams are abundant may generally be said to be from 1,000 to 2,000 feet above the sea. To the south of Chota Nagpore again, on the west side of Orissa, are the Orissa Tributary Mehals, a hilly country containing a considerable population. There are forests of sal on the hills, which run parallel to the line of coast from north-east to south-west, to near the south-west extremity of the province, the Chilka lake, on the banks of which, as along the sea shore of Cuttack, much salt is manufactured.
The mountainous tract to the east of Bengal has some summits with an elevation of I1,000 or 12,000 feet, and our settled hill districts rise to 6,000 feet. They abound in coal and iron ore intermixed with limestone of excellent quality. The eastern boundary of Bengal, at the extreme north-eastern corner of Assam, is formed by a spur from the Himalayas, and from this point the hilly range is never entirely broken to the south of Chittagong. First to the north-east are the hill regions of the Singphoo and Abor tribes, then the Naga hill districts to the south of the Assam valley, continued by the Munipore, Cachar, and Tipperah hill to the Chittagong Hill Tracts: meanwhile the GaroKhasi-Jynteah range strikes out parallel to the Himalayas up to the bend of the Brahmaputra; a considerable area of this high country is as yet insufficiently explored. The inhabitants are for the most part primitive in their habits, and belong to aboriginal races, of IndoChinese type. The jungles are intensely thick. Of the more remote parts of these hills little is known except from the reports of survey parties and such personal narratives as are depicted in Captain Lewin's "Chittagong Hill Tracts."
The Assam valley is almost a perfect flat, studded with clumps of plains little conical hills rising abruptly from
111the general level to the height of 200 to 700 feet, rich in rivers and in mineral treasures, coal of a fair class being found; the climate, too, is very favorable to the indigenous tea-plant, which grows luxuriantly. The greater part of Bengal and Behar are uninterrupted flats, subject to inundation, rich in black mould, some portions naturally more fertile than others,—the Dacca division being so fertile that it has been called "the granary of Bengal." Drawing a line southwards between Bancoorah and Burdwan, carrying it on past Midnapore and down towards Balasore, it will be noticed that to the west the ground partakes of the character of the Chota Nagpore plateau, granite being found overlaid with carboniferous sandstone, containing iron and coal in great abundance, and the climate in consequence being of a drier character.
There are no lakes of importance besides the Chilka, though there LakM are numerous jheels, or shallow sheets
of water, which expand or diminish owing to the season. The most remarkable are the Monda, Dulabari, and Chullum jheels in Rajshahye, the Aka in Jessore, and the great jheels in Backergunge.
Although Bengal is situated for the most part without the tropical
zone, its climate is characteristically
p 0' tropical. The mean temperature of
the whole year varies between 80° (in Orissa) and 74° (in parts of Assam), that of Calcutta being 79°.
la the animal range of their temperature, as well as in point of humidity and rainfall, the eastern and western portions of the province are strongly contrasted. In Cachar, nearly 200 miles from the sea, the mean temperature of June is 82°, that of January 64 6°, and the highest and lowest temperatures recorded during five years, viz. 99° and 43°, show an absolute range of 56° only. At Chittagong, on the sea coast, the recorded range does not exceed 49°. On the other hand Patna has a mean temperature of 87*2 in June and 60 7 in January, and in 1869 the highest and lowest temperatures registered were 116-3° on the 12th May, and 36-9° on the 3rd and 4th of January; the absolute range of this year was therefore 79-4°. It is probable that some parts of Behar—the neighbourhood of Gya, for instance— experience a range somewhat greater than that of Patna.
The highest temperature recorded in Calcutta during the last 18 years is 106°, which has been reached twice only, viz. ouce in 1867, and again in May of the present year (1873). The lowest temperature, 5im7, has been recorded also twice, viz. in January 1860 and 1864, and 52 8 has been observed twice, viz. in January 1857 and 1861. The extreme absolute range of the temperature of the capital is therefore a little over 53°, and the mean temperatures of December and May are 68*5 and 85 respectively. The annual rise and fall of temperature exhibits some other local variations. Thus in Orissa and the western part of the Gangetic delta December is the coldest month of the year; elsewhere the mean temperature of January is somewhat lower. This difference is due to the sea winds setting in on this part of the coast very early in the year, whereas in Behar their influence is not felt till much later in the season.
During the rains the temperature of the Hazareebaugh plateau, to the west of the delta, falls more rapidly than that of any other part of Bengal. Between May and October the fall at Hazareebaugh is rather more than 11°, while at Berhampore, under about the same latitude, it is only 44°, at Calcutta little more than 3°, and even at Patna it does not exceed b°. This peculiarity appears to be due principally to the cloudiness of the plateau in the daytime, whereby the sun's heat is rendered less intense, and to the greater radiation at night. This fact has an important bearing on the value of Hazareebaugh as a station for European troops, and as a sanatarium for invalids from the plains
The high humidity of the atmosphere in Bengal, and more especially in its eastern districts, has become proverbial; and if the term be used in reference to the quantity of vapour in the air as measured HumWitj kv its tension, the popular belief is
justified by observation. But if used in the more usual sense of relative humidity, that is, as referring to the percentage of vapour in the air in proportion to that which would saturate it, the average annual humidity of a large part of Bengal is sensibly lower than that of England. A comparative table is subjoined of the mean vapour tension aud relative humidity of London and Calcutta in each month of the year, and the mean of the whole year; the data for the former place being taken from an essay on the climate of London by the late Professor Daniell, those for the latter from the results of the hourly observations registered at the SurveyorGeneral's Office, Calcutta, and computed in the Meteorological Office of Bengal. The former are deduced from 17 years', the latter from 14 years' observations.
The quantity of vapour in the air of Calcutta, relatively to the dry air, is then, on the average of the year, about twice as great as in that of London; but the relative humidity of the former equals that of the latter only in the three first months of the rains, which are among the driest months of an European climate.
The absolute humidity of the atmosphere is greatest on the coast of Orissa and the Soonderbuns, and diminishes inland as the distance from the sea increases. In the cold weather and spring months this decrease is rapid everywhere except in Eastern Bengal. In Cachar, however, the quantity of moisture in the air is as great as on the coast of Chittagong, and even exceeds it, excepting between the months of February and May. During the hot weather months the proportion of vapour to dry air increases steadily and rapidly in all that part of Bengal in which the hot westerly winds are not a regular phenomenon of the season; that is to say, on the Gangetic delta, in Eastern Bengal, and on the maritime plain of Orissa; but on the high ground further west, and in Behar, as well as generally in the North-West Provinces, its increase is slower up to May or June, and it then rises rapidly almost to an equality with that of the maritime region. This is clearly traceable to the winds, since in the former region winds from the sea predominate throughout the hot season, mitigating its temperature indeed, but at the same time rendering the atmosphere damper, and producing, when the air is calm, that oppressive feeling of sultriness which is so trying to persons accustomed to the drier atmosphere of Beharand the NorthWest.
The districts of Eastern Bengal, including Cachar and Sylhet and the Himalayan Terai, are those of the heaviest rainfall. Their average annual fall almost everywhere amounts to 100 inches, and on the exposed hill flanks, and at their foot, even this large amount is greatly surpassed. Thus Sylhet has an annual average of 141 inches, Darjeeling 126
inches, the Rungbee cinchona planRa,nfaU- tation 175 inches, Buxa fort 280
inches (the average of three years), and Cherra Poonjee the enormous amount of 527 inches; this last is the highest average rainfall hitherto recorded in the world. The rainfall is also higher on the plains of the coast than on those lying more inland. Thus Saugor Point has an average of 87 inches, and Calcutta 66; False Point 74 inches, and Cuttack 52-5. The lowest rainfall in the provinces under the Bengal Government is that of the southern portion of Behar, including Monghyr, Gya, and Patna, where the annual fall does not much exceed 40 inches, and in the case of the last mentioned station is only 37 inches. North of the Ganges it increases gradually up to the Himalaya, and on the south up to the high ridge of forest-clad country which is drained by the Soane, the Damoodah, and their tributaries. In this tract, where the monsoon winds from the opposite coasts of India meet, the fall of the few stations that have hitherto furnished registers ranges between 50 and 60 inches. In Calcutta the highest rainfall on record is that of 1871, when it amounted to 93*31 inches; the lowest (if the register can be trusted) during the last 36 years is that in 1837 (the first year of the series), when the registered fall was as low as 43 61 inches. In subsequent years the lowest falls were those of 1838 (53 inches), 1853 (52-08 inches), and 1860 (52'61 inches). In the present year (1873) the rainfall up to the middle of November has only been 44 31 inches. The Cherra Poonjee register of 1861 records a fall of 805 inches, of which 366 inches fell in the month of July alone. It is said that 150 inches have been known to fall in six days. 12 inches of rain in one day is far from unusual at Cherra Poonjee. On the 13th June 1861 an equal quantity fell in Calcutta within 24 hours. At Mozufferpore in September 1871 19 inches of rain fell in 86 hours.
By far the greater part of the rainfall of Bengal falls between the months of June and October. Showers occur also in the hot weather months, and in the months of February and March hailstorms are not unfrequent. In the eastern districts rain occurs occasionally in the cold weather months, but is less common in the Delta and the country further westward, excepting in the North-West Provinces and the Punjab. In the eastern districts and in Assam rain is more abundant in all the earlier months of the year; in April the rain sets in heavily and reaches its maximum about June or July. Further to the west the rains usually set in in J une, and J uly and August are the months of the heaviest fall.
Except at the hill stations, and in the immediate neighbourhood of the hills, the average proportion of cloud-covered sky varies between one-third and one-half of the whole. At Darjeeling on an average the proportion of clouded sky to sunny sky is as 2 to 1. In Lower Bengal generally it is about 1 to 2, being however rather higher on the coast.