PETROLEUM, Earth-oil.
Neft, . . . Amu. Kesoao no abra, . .
Yai-nan, . . . Bumf. Minsk tanab, . . Maim Thi-yu, . . . . CHIN. ' Japoo, . . . SUMATRAN. Petrole, . . . PR. Man tylam, . . . TAM. Stein-ol, „ . . GEC. Matti tylum, . . .
Matti ka tel, . . HIND. 1Thoom) tylam, . . „ Petroleum, as its name indicates, is an oil-like exudation from rocks, which was employed in medicine in the earliest times, though little used now. It is very abundantly diffused, and in various other forms. It is nearly allied with bitumen on the one hand, and naphtha on the other, between which it occupies an intermediate place, the principal distinction being a difference of consistency and colour. Bitumen in its several varieties, known as mineral pitch, asphalte, pisas phaltum, etc., is solid or nearly so, and black or dark coloured ; naphtha is perfectly liquid, and light in colour. Petroleum, earth-oil, or rock oil, is viscid or oily, and greenish or reddish brown in colour.
At Kafir Kot, it exudes from brown bituminous sandstone, and is usually found floating on the surface of springs ; Ratta Hotar hills ; at Jabba, a hamlet of Kussan, west of Chakrata, and about 9 miles east of Kalabrigh ; at Dhadur, 3 miles west of Kabbakhi, in the Salt Range ; at Narsinghpur, in the Salt Range ; at Jabba, near Nurpur ; in the Algad ravine at Kafir Kot on the Indus, and in smaller quantities at some other places. It is a pro duct of the hills on the west side of the Indus, called Tuklo Itiesar, near Banu and Tank, pro curable in the bazar of Debra Ismail Khan. It is of a reddish colour. In Barbadoes and Trinidad, petroleum is found floating on springs of water ; in Britain, as at Colebrooke Dale, etc. ; in many parts of Europe ; at Baku, on the shores of the Caspian. Springs of it occur near Hit, on the Euphrates, and were noticed by Dr. Winchester in Boni. Geo. Trans. iii. p. 15.
Petroleum has been found at a place called Makoom, a few miles beyond Jeypore on the Dehing. Petroleum is very plentiful in Upper Burma. At Yevnan-gyoung there are about 150 wells being worked. The daily out-turn is esti mated at 15,000 viss. The total yield of these wells is 6,000,000 vise, or 9375 tons per annum.
The total quantity of earth-oil yielded by the wells of Upper Burma is 6,600,000 vise, or 10,312f tons per annum. There are many abandoned wells, and wells that produce very small quantities of oil. At Pagan there are about 50 wells ; they yield daily 1500 viss of oil, which the earth-oil contractors are allowed to purchase. The oil from these wells is obtained in a more liquid state, and more resembles naphtha. It is better suited for lighting purposes than the Yeynan gyoung oil.
The town of Yeynan-gyoung is the centre of a small district in which there are more than five hundred petroleum wells in full activity. The district consists of a sandy loam, resting upon alternate strata of sandstone and indurated clay ; under these is a layer. of pale blue argillaceons schist, of considerable thickness, impregnated with petroleum, and resting upon coal. The petroleum flows into the well when it is sunk a few feet into the schist, and when it begins to fail the well is deepened. It is remarkable that no water ever penetrates into these wells.
In Cheduba there are 22 wells ; in Ramree, 13 wells, each producing two maunds in the season, the aggregate being 70 maunds annually. The produce might be increased some 10 to 20 maunds by digging more wells. The petroleum is thick
and dark coloured. It is used for burning, also to pay boats' bottoms, and as a wood varnish. Two wells were said to yield a clear bright fluid.
It occurs at Akyab, Ley Doung, in the Padoung township of the Prome district ; at Thayat Myo, and at Khyouk h'pyoo, in Upper Burma ; at Pagan and Yeynan-gyoung ; is very abundant at Yeynan-gyoung, or Earth-oil creek ; very abund ant in Western China, and also in Sumatra, Sulu Islands, and Japan.
In the island of Cheduba, the method of col lecting it is simple. The earth is turned up to a depth of two feet, and a bank of soil, raised round a square of about 20 yards, is distributed so as to form it during the rains into a shallow pond of about the above depth. The surface of this pond is in a constant state of ebullition from the escape of gas, with which comes up the petroleum. It collects on the surface in three different forms. A green fluid oil first spreads itself over the spot where the gas is bubbling up. As it extends, its edges exhibit a brown curdled substance resem bling half-congealed dripping ; and amongst this, as it becomes thicker, is seen gathering in spots a dark-brown substance of the colour and con sistency of treacle. This latter is used to preserve wood, to saturate paper for umbrellas, and is sometimes burned ; but the fluid of a green colour is that mostly used to supply lamps. The curdled substance is used with the dark in the coarser purposes to which it is applied. This is the least valuable, and sells at five pots for a rupee ; the other two at three pots for 2 rupees. A bamboo is used to skim the surface of the ponds, and bring the substance to the bank ; it is scooped up with a cocoanut shell, and put into the pot. It floats so lightly on the water that this process is quickly and effectually performed. The break of the day is the time chosen for the opera tion, as, from the cooler temperature, it is then of harder consistence on the water, and more easily and cleanly skimmed. In the heat of the day it ,becomes so fluid as to make it difficult to collect without a large proportion of the water. In the months of March and April the pond gradually dries up, and the oil can then be no longer collected from out the soil. The pond is then dug, and the whole soil in it is as much disturbed as possible. On this operation depends the quantity to be yielded during the next season, and the deeper it is dug, the larger will be the produce. A sort of superstitious fear is attached to these ponds, and on no account would a native dip his foot in its water, though he will not hesitate to dig the soil when dry, nor to handle its produce, to which no sort of deleterious property is attri buted. The state of ebullition, without apparent heat, may occasion this feeling among them. The ponds are surrounded by a rough hedge of stout sticks, to preserve them from the intrusion of buffalo or deer. Insects were seen in them. No heat is perceptible at the surface, the thermometer where the greatest ebullition was going forward showing but 2° more than the atmosphere, viz. 74°. No doubt this mineral product might, with ease and little expense, be increased to a very large amount ; and the oil has yet perhaps to be better known and better appreciated than now, when its value will in all probability be much increased. Britain imports 59} million gallons.