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(Plate I.) shew it; a is a mass of sand heaped up to the height of about four feet, on three sides of a ndnd, or baked earthen pot, which measures from one and a half to two feet in height, and fifteen to eighteen inches in breadth; it is fixed into the mass of sand, and rests upon three, and sometimes upon two, pieces of stick or bambu placed across the top of a receptacle, in which lies a small ghara or pitcher immediately below it, so as to receive the drops of salt-water as they fall down through an aperture cut in the bottom of the large mind or pan. Over and perpendicularly across the aperture is placed a thin bit of stick or bambu, sufli. cient to bear a small piece of coarse cloth, which is laid across the stick, depending down through the opening to the distance of about three inches, and directed to the little pitcher below; upon the stick is placed an irregular spherical fragment of tile, or earthen pot, broken angularly, so as to allow the water which disengages from the sand to flow beneath it, and pass along the piece of cloth that rests upon the stick to the receptacle below. In addition, a second piece of cloth is laid over the tile, so as to cover, it, and prevent any sand from escaping underneath the latter, and mixing with the filtered liquid; every thing being prepared, the filler throws into the mind a quantity of the saline collection, until the vessel is filled to within two or three inches of the top, when he fills up the remaining space with fresh water, taken from the river close by; the water in a short time percolates the sand,and falls into the pitcher by the means above-mentioned, and is found to consist of a brine, exceedingly salt in taste at first, but diminishing afterwards ac. cording to the quantity of water which is added from time to time, as the upper surface subsides. The liquid in the small pitcher is emptied into a third pan, in which it is conveyed to a chulah or clay fire-place, sometimes prepared at the spot, but more frequently at the manufacturers’ abode, where it is subjected to the action of the fire, and allowed to simmer under a slow heat, until the liquid has all evaporated, and the salt remains at the sides and bottom of the vessel. The colour of this salt is brownish ; it is of an excellent quality, and is much superior to the black
‘salt which is given to horses, and if it were refined, would, I doubt not,
be fit for the table; the flavor being very good when the salt is fresh. It is rather a curious circumstance that salt should be found mixed
with the sand of the Jumna,a river of which the water is sopureandfresh to the taste, (although it is considered by the natives as almost unfit to he drank in the hot and rainy seasons;)the quantities gathered are, however, under the present management of the poor, trifling, and but barely suflicient to give the laborer a sustenance, although he is allowed by the Raja in Bundelkhand a portion or plat of sand free to himself and family
for the season. The rates, quantities, &c. are asfollows:
Each of the three persons, (sometimes women are employed,) can gain their anna per day by making two and half seers of salt, which sell at the rate of one rupee per maund. They workeach from sun-rise till about noon, and not later, as they consider “ sufficient for the dayis the evil thereof ;" besides, after twelve o’clock, the sun becomes too powerful for them to work out of doors.
The locality of this salt preparation is on the Bundélkhand side of the river, about thirty-six miles by water, and twenty-four by land, above Culpee ,- is under the authority of the Budek Raja, and is situated opposite to the village of Marhapoor, nea Karimkhan (or Kurmookah Ghat), where the chief operations of removing the rocks which impeded the navigation of the J umna have ‘_been carried on for some time past.
The favorable season of the year for this salt operation is only in the hot dry months of April, May, and June, before the river rises ,- for on its subsidence, which takes place at the close of the rainy season, the sun must be allowed to gain some power before these people can attempt a renewal of the process, because the only sand from which the salt is disengaged is drawn forth and raised above the general surface of the bed by the direct influence of the sun’s heat, which is not sufliciently powerful in the cold season to produce such an effect. I am not aware whether the little hillocks of swollen-up sand subside again or not after the sun's departure below the horizon, but I should think that they do not. A number of sand mounds, fifty or more, raised here and there, some given up, and the rest in progress, were to be met with in June last ,- butI should scarcely think if the preparation of salt were carried on after this manner on a more extensive scale, that it would reimburse the specutor for any large sums of money that he might hazard in the manufacture of the article.
_ -It appears, from the natives’ account, that four baskets filled with this saline collection weigh about two maundsof forty seers each (160 lbs.), or forty lbs. eachbasketful ,- also, that half aseer (one lb.) of salt was extracted from a maund weight, or eightylbs. of sand. Thata day’s work, consisting out of doors, of six hours, (passed in collecting, filling, and filtering tillnoon; and the rest of the day in the evaporating process,) enabled the manufacturer to prepare a sufiicient quantity of salt for him and each of his family to gain an anna a day clear, for the fire cost him but little, as he gathered or picked up the fuel, consisting of old sticks and gabar, or dried cowdung, and he purchases the earthen pots for a mere trifle, and they last a long time, excepting the one subjected to the action of the fire. This anna, equal to three half-pence, is found to be sufiicient for the il1diVidual’s
maintenance; but I suspect he gains something more, as he stated that to every labourer whom be employed in excess to his own family, he paid hire at the rate of an anna a day.
He sells the salt unrefined, at the cheap rate of one rupee per maund of forty seers, but this afterwards sells in the towns or cities whither it is conveyed, at a rate triple or quadruple (as I understand) its first price; it however previously undergoes a process of refinement. Half a seer of salt per diem is prepared from each of the mounds in which only one ghara is fixed, so that to enable a family of three persons each, to get their anna a day at the above rate of one rupee per maund, they must keep up fifteen sand mounds, with a mind in each.
I do not know what is the proportion of salt found in the superficial hard crust of the dry earth at Cawnpoor*, where I have seen people scraping the ground for it, to the depth of half an inch,or more; it would be worth while to ascertain, but I should think the proportion of salt there exceeded that found in the bed of the J umna, although it is probably not so good.
As the mind was only filled once a day with the sand, and as half a seer, equal to one lb., of salt was extracted fromit during that period, the proportion of the latter to the former will be easily found; for,
The ghara contained (by calculation).0.8836 decimal parts of a cubic foot of sand; considering the space that was filled with it to be a hemisphere, and the specific gravity of sand being 1520, the weight of that quantity will be eighty-four lbs. nearly ; therefore the proportional weight of salt extracted from thus much sand, will be one lb. of salt to eighty-three lbs. of sand, nearly. The native’s account agrees extraordinarily well with this calculation, for he said that half a seer of salt was extracted from a maund weight, or eighty lbs. of sand, as before noticed; thereby differing only three lbs. from this statement: his assertion therefore is to be relied upon as nearly correct.
VI.—On the Saline Nature of the Soil of Ghazipoor, and Manufacture qf Common Salt, as practised by the Natives qf the Villages of Tuttulapoor Ratouly, Sahory, Chilar, and Becompoor. By Mr. J . Stephenson,Supt. H. C. Saltpetre Factories in Behar.
The surrounding soil in the vicinity of the above villages in the district of Ghazipoor contains a large proportion of various kinds of saline matter, such as muriate, sulphate, and carbonate of soda, together with
nitrate of potass (saltpetre) and nitrate of lime.
Near the village of Ratouly, about four coss N. W. of the station, an opulent native is making a large new tank. Here the excavation already made afforded me a section of six feet deep. The first four feet from the surface is formed of mud and clay: below this, two feet of kankar contained a large proportion of saline matter, consisting of sulphate and muriate of soda. The efllorescence is in such abundance, on the sides and bottom of the excavation, that I gathered it in handfuls, to obtain an average sample. The bottom of the tank was covered with kankar in nodules and lumps recembling stalactites.
' See Journal vol. i. page 503.
The circumstance of so much saline matter being found here at the depth of four feet below the surface, resting upon and impregnating the stratum of kankar, naturally leads me to the supposition (taking all appearances into consideration) that a constant, but slow, decomposition is going on between the carbonate of lime, containedin the kankar, and the muriate of soda in contact with this singular stratum. Hence the formation and development of carbonate of soda, in the same manner as observed in the Natron lakes, and beds of Egypt. by the justly celebrated French chemist BERTHOLLET, though, from his description, the appearances in that country are more strongly developed, than I observed to be the case at the above place. The upper part of the kankar bed being undulated, it therefore frequently crops out at the surface, and of course the saline earth in proportion. This accounts for the efllorescence appearing in patches, as it were, especially when moisture is retained in the soil at all seasons, which is the case in the vicinity of jheels. However, as I wish to confine myself to facts alone, I leave this subject to be taken up by others better acquainted with geology than myself. There seems (as far as my observations extended) to be no want of materials for nature to operate upon ,- for in the space of a few miles I found the earth to contain sulphate, muriate, and carbonate of soda, with here and there the nitrates of potass and lime, distributed in patches through a large tract of country.
Near the above excavation for a tank, and close by the village of Ratouly, is established the largest salt factory that I had an opportunity of inspecting. I generally found them situated where the patches of muriate of soda predominated, and the following notice attempts to describe the operations of the manufacture as it came under my own observations during my visits to the factories for the purpose.
The manufacture of salt is commenced on the latter part of the month of February, and is carried forward till the commencement of the rainy season; for being upon the principle of solar evaporation, the operations can only be carried on during the dry hot months.
The first operation is to scrape the surface of the soil (in the same manner as saltpetre is scraped off and gathered in Tirhoot), and collected in heaps near the filters. The latter are the same in principle, though different in shape and size to those used for the manufacture of saltpetre, being an oblong square of fifteen feet by five, and not more than nine inches in depth. They are built with the stiff kankar clay, with the stalks of sugar-cane laid crosswise, to form the bottom of the filter, instead of bamboos and mats used to form the bottom of the saltpetre filters. A few which I saw had a layer ofjungle grass laid over the canes, which rendered the filtering process more effective.
About fifty maunds of the saline earth is operated upon, at each charge. This raw material being laid on the bottom of the filter, so as to form an uniform thickness of about five inches, and trodden down to the desired hardness by the feet of the operator. Water, from a well close by, is then poured upon the earth to the depth of three or four inches, and the whole suffered to remain tranquil for the space of several hours, during which time, the fluid finds its way through the earthy bed, and dissolving the salt in its passage, runs off in the form of a weak brine, by means of a spout into an earthen vessel used for a receiver.
The brine thus obtained is more or less charged with a colouring matter from decomposed vegetable matter and oxide of iron which the kankar soil contains. On a subsequent examination of the brine from several filters, I found the average to give a specific gravity of 1.095.
The brine obtained in the above manner next undergoes a subsequent process, as follows :—on the surface of the ground, near to the filters, eve..porating beds are constructed of about twenty feet square, and not more than four inches in depth. The bottom is formed of the nodules of kankar limestone, plastered over with a cement of the same materialI similar to the roof of a pucka built house. These pan-like squares are for the purpose of solar evaporation. A thin layer of cow-dung is spread over the surface of this evaporatory, and the ras (as the natives term the brine) is poured over, till the dung is saturated. The evaporation goes on, and when the mixture is sufliciently dry, the saturated dung is collected into a large heap, in order to be burned, or calcined, in the same way that kluira lon earth is burnt in Tirhoot, except that the cowdung serves instead of rice-straw for fuel.
The calcined saline mixture is then removed to a filter (formed of clay), of smaller dimensions than the one above, which I have attempted to describe, (being only about five feet long, three broad, and two deep,) when it is again subjected to the process of filtration. But in this second process, no more water is used than is necessary to dissolve the common salt (which is known to be more soluble than most other salts) contained in the calcined mixture; consequently a very strong solution of brine is obtained from this second operation. By the process of burning, the colouring matter is in some measure destroyed, so that the brine from this second operation is less coloured than that resulting from the