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December and January are, on the whole, the brightest months of the year, but November, February, and March, are almost equally serene. June, July, and August, are the months of greatest obscurity. In the former months the proportion of cloud is on an average from 10 to 15 per cent., in the latter months from 65 to 85 per cent.
The wind system of Bengal is so often referred to as a familiar
illustration of the monsoons, that it
The wind system of Bengal.—The mon- might Seem almost superfluous to re
800n8- describe a subject treated of in every
text book on meteorology. But it appears from recent investigations that, however well-known at sea, the character and origin of the monsoons on the land have been very generally misunderstood. The monsoons are not two undivided currents flowing to and from Central Asia during about equal periods of the year, but appear rather to consist at each period of at least two principal currents,—the one tending to or from Northern India, the other to or from the interior of China; and there are probably other minor currents originating or terminating at other centres. The Indian branch of the winter monsoon originates in the plains of the Punjab, the Grangetic valley, the uplands of Central India, and also in Upper Assam, and blows as a very gentle wind towards the two great Bays that wash the east and west coasts of the peninsula. During this season a southerly wind prevails steadily on the Himalaya at heights above 6,000 or 8,000 feet, descending lower on the western than on the central part of the range. This appears to be the upper return current of the winter monsoon, and corresponds to the antitrade of the trade-wind region. It descends on the plains of upper India, where the atmosphere is characteristically calm at this season, and brings the winter rains, on which the rubbee crops depend. It is less frequently felt in Lower Bengal, where the wind is variable from north and north-west; but to the eastward, in Cachar, southerly winds are very prevalent at the winter season. In Northern India the two branches of the northerly monsoon appear to diverge towards the opposite coasts, from a line characterized by a ridge of higher mean barometric pressure, which passes from the Punjab through Benares to Cuttack. This monsoon ceases on the coast line of Bengal in the month of February, when in the lower atmosphere sea winds set in. At first these are restricted to the immediate neighbourhood of the coast, but as the season advances and the heat of the interior plains rises under the influence of the returning sun, they penetrate further and further inland, and are drawn from greater distances at sea. In the interior of India the wind becomes more westerly and blows towards lower Bengal and Chota Nagpore, not as a steady current, but as day winds, which in April and May are highly heated by the parched and heated soil, and constitute the well-known hot winds of those months. Where these two currents meet, the thunderstorms well known as north-westers are generated. Like the thunderstorms of Europe and the dust-storms of the Punjab, they are due to convection currents, and in Bengal owe their prevailing movement from the west or north-west quarter to the strength of the land wind, which maintains its course in the upper atmosphere above the opposite
sea-wind, which is felt at the land surface. At this time the north-west wind continues to blow unsteadily in the south of the Bay, but calms are not unfrequent, and it is not till June that the southerly winds of the Bay become continuous with the south-east trades of the South Indian Ocean, and that the south-west monsoon, properly so called, sets in in India. This blows from both coasts, and the two branches meet along a line which about coincides with the southern margin of the Gangetic plain. Both tend towards the Punjab, the region of the greatest heat at this season, and becoming gradually drained of their vapour in their passage over the land, that which remains on their reaching the plains of that province suffices only to afford a scanty rainfall, inadequate to mitigate the temperature, and only rendering the heat more oppressive by increasing the relative humidity and diminishing the evaporative power of the air.
As an element of climate, apart from its secondary effects on the winds, and consequently on the humidity, rainfall, &c, the pressure of . . the atmosphere is, as far as is known
Atmospheric pressure. . ,* e i ■.•
at present, of subordinate importance. In Bengal, as in most tropical countries, its variation, except during the passage of cyclones, is small, scarcely amounting to an inch on the extremes of the year. The average pressure of the air in Calcutta, 18 feet above sea-level, is equal to that of a column of mercury at the freezing point, 29 793 inches in height, or to 14 61 tb on the square inch. It is highest in December, when the mean pressure similarly estimated amounts to 30 041 inches, and lowest in June and July, when it averages 29"551 inches.
The storms prevalent in Bengal are of two classes: first, those of stormt the hot weather, already noticed, which
m are formed over the land, and are
of the nature of convection currents, like the summer Btorms of Europe; and second, those more extensive and destructive storm3 that originate over the Bay of Bengal, and are most frequent at the changes of the monsoons. These latter have received the distinctive name of cyclones, and the name is perhaps as good as any other, since in them a vorticose motion of the wind is a strongly marked character, and one of great practical importance; but it is by no means a character peculiar to these storms, since it may frequently be observed in a slight degree in the ordinary north-westers; and tornados, which are apparently nearly a severe form of the north-wester, differ from a typical cyclone only in their originating over the land, in their inferior size and shorter duration. The dust-storms of the Upper Provinces also have been shewn to consist of one principal and numerous minor vortices, exactly like the larger storms of oceanic origin. The pressure of the wind in tornados, and even in ordinary north-westers, is sometimes comparable with that of cyclones, and within a limited area the former are not less destructive. There is an important difference in the character of the surface wind in these two forms of land storms. In the north-wester the violent wind usually precedes the storm, blowing outwards, and being in fact a descending current brought down by the friction of the falling rain. The centripetal currents which feed the storm are not felt at the ground surface, though they may frequently be traced in the motions of the lower clouds. In the tornado, on the other hand, as in the true cyclone, the violent surface winds are centripetal and vorticose.
Cyclones begin in all cases over the Bay of Bengal, and the more
violent and extensive storms, which JC onea' alone reach the land, probably require
many days to form before they move forward from their place of origin. Some of the most destructive that have passed over Bengal have proceeded from the neighbourhood of the Andaman and Nicobar Islands. Their relative frequency in the different months of the year is shewn in the following table,which includes storms of all parts of the Bay, and those that have been felt on all parts of its coasts, Bengal included.
Of these seventy-three storms, twenty-three have been felt in Bengal or on its coasts, and all between the months of April and November, inclusive. Their course is usually north, across the Gangetic delta, north-west from the Orissa coast. The motion of the wind is in an involute spiral, revolving in a direction opposite to that of the hands of a clock, as in all cyclonic storms in the Northern Hemisphere. The greatest preasure of the wind in these storms is yet to be ascertained. The highest that has been registered in Calcutta by an Osier's anemometer is 50 lbs. to the square foot, but this was in a storm of no remarkable violence, and one which did but little injury in Calcutta. The centre of the storm at the time was passing some 15 miles to the east of the city, and the barometer stood at 28-712. In the far more severe storms of the 2nd November 1867 and the 5th October 1864 the anemometer was blown away, under a pressure of 36 tj5s. to the square foot, so that no register of their maximum force was obtained. There is a prevalent impression that cyclonic storms have been more frequent of late years than formerly, but the belief does not appear to rest on any sound basis of fact. Since the destructive storm of October 1864 the attention of the public has been attracted to the subject more steadily than in former years, and many a storm that would have escaped notice, or if reported in a newspaper paragraph would have been speedily forgotten, is now made the subject of general conversation for the time, and recorded with all procurable detail in the annual meteorological reports. To this cause probably may be attributed the popular belief in the greater frequency of storms in recent years.
CHIEF STAPLES, &C.
Rice is the principal food-grain throughout Bengal Proper, and
is largely cultivated and consumed Food-gbaiks. over the whole of the province.
^ The varieties of rice are infinite, but
the rice or paddy (dhan) is divided into two distinct main crops, locally known as the aoos and the the amun. The aoos rice is mostly raised upon the high level lands. It is sown with the first showers of the spring and gathered in July and September. The name of this rice (from Sanskrit *n*9, 'early') is derived from the rapidity with which it ripens. It requires more attention in cultivation than the amun, and is more liable to failure from the accidents of the seasons. It is not transplanted, but reaped from where it is sown.
The amun (pprfs, or 1 winter') rice is of two principal varieties— one sown broadcast, and the other transplanted. The transplanted amun ropa, or rooya dhan, as it is called, is the commonest variety of rice in Bengal. In the first instance it is sown on high land. Afterwards, when the rain renders it sufficiently moist, and the seedlings are about a foot high, they are gradually transplanted to marshy soil, as this becomes ready for them in about 10 inches of water. This land need not be of the lowest description, but it must be such as in the rains is covered with water. The rice grows in water, knee or thigh deep. It is sown in April, transplanted in August, and reaped in November, December, and January. In some parts of Eastern Bengal this rice is transplanted twice,—first, into high dry land, where it is well manured and weeded, and then, when about two feet high, to wet marshy soil.
The amun sown broadcast and not transplanted varies in different localities, and has various names, but is generally known as boron, boona, or booya. Even this is occasionally transplanted, but not usually. It is sown in the beds of bheels and rivers, and as the waters rise the rice grows with them, and the stem at times attains the length of twelve or even twenty feet. Of all kinds of rice this is the most rapid in its growth, frequently shooting up twelve inches in twenty-four hours as the inundation rises. Some species of this dhan are capable of bearing submersion for seven or eight days, if the water which has risen suddenly be clear. If it be submerged in foul water, the plant dies in a day or two. This description of amun is sown and reaped at the same time as the transplanted species.
The aoos and amun rice are known as beali and sarud in Orissa, and as ahoo and sali in Assam. In Behar the early and late crops are known as bhadoi and aghani.
Besides these there is another principal kind of rice, the boro or spring crop of dhan, raised on churs and in low bheel lands and the edges of jheels, where the water is intercepted and the plant uprooted from nurseries stuck deep into the mud during the cold weather. The crop is reaped in April, May, and June, and its success depends much on irrigation.
The above are the principal descriptions of rice grown in Bengal, but there are innumerable minor varieties familiar to the peasantry, and many of which are peculiar to particular localities.
Eastern and Central Bengal and Orissa are the principal rice-producing tracts. The aoos crop, which produces a coarse rice, is usually consumed locally; the winter and spring rice is exported. From the whole of the Chittagong division, and, broadly speaking, from the Dacca division, there is a large export of rice. Although a great deal of rice is exported from the Dacca district, the greater part is brought from Tipperah, Sylhet, and Mymensingh. Furreedpore does not feed itself entirely, and receives large exports from the above districts and Backergunge. The Backergunge outturn of rice is probably larger and better than that of any other district in Bengal. From the Soonderbuns of Backergunge, Jessore, and the 24-Pergunnahs, there is a very large supply. In the Rajshahye division also the cultivation far exceeds the requirements of the people, and rice is largely exported. Dinagepore is the principal rice-producing tract in the division. From the Maldah and Dinagepore districts the export up-country registered at Sahibgunge amounted last year to 1,500,000 maunds, from the Rajshahye district 320,000 maunds, and from the Moorshedabad district about the same amount. From the Dacca division the up-country export registered at the same place was more than 400,000 maunds. The Bogra rice export is estimated at 600,000 maunds j Rungpore is not yet an exporting district, though there is a surplus cultivation ; the proposed Northern Bengal Railway will doubtless remedy this. While Moorshedabad exports largely from the west of the district, it receives large imports into the east from the districts on the other side of the Ganges. In the Burdwan division there is a surplus cultivation of rice in Midnapore and Beerbhoom, and a large export. The export from Midnapore is estimated at 1,700,000 maunds annually. From the Bhaugulpore division the cultivation of rice is not much more than is required for local consumption. The produce is inferior. Occasionally exports are consigned to Behar and the NorthWestern Provinces. In the Purneah district there is, however, a Burplus, and rice finds its way in quantities to Darjeeling, and also into both the Calcutta and up-country markets.
In Orissa there is a large rice cultivation, and the exports are considerable.
The principal inland imports of rice grown in the interior are into Calcutta for export by sea, and into the Behar provinces. Large quantities are also sent into Assam. Bancoorah, Hooghly, and Nuddea, are the principal Bengal importing districts.
The amount of rice exported from Calcutta annually exceeds 10,000,000 maunds. There is a considerable sea export also from Chittagong.
In Behar also rice is a main staple of food, though where the „ . . . „ , soil is high and dry one of the two daily
meals is usually made of wheat, maize, peas, or inferior grain of some sort. Maize and barley are perhaps cheaper than rice, but rice is the favorite food, and those who can afford it take it twice a day; those who cannot, once; but only the very poorest, if even those, eat no rice. It may be roughly stated that in Behar ordinary cultivators eat their meals half rice and the other half in cereals, millet, or pulses.
Murwa and kodo are both cheaper than rice, and are much eaten Murwa — Kodo the lower classes. Kodo is a millet,
the size of a canary seed; each plant has a longish ear, longer and thicker than an ear of corn, and containing about an egg-cup full of grain; it is eaten boiled like rice, or sometimes in chupatties. Murwa is a very cognate grain to kodo, but