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MANUFACTURES.

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premises for reducing the blubber into oil, consistingcommonly of the following articles.

A copper vessel or boiler, from three to six, or eventen or more tons capacity, of a circular form in the hori-zontal view, and elliptical in the perpendicular section,is fixed at the elevation of six to ten feet above the ground,provided with an approximate furnace, and covered witha tiled or slated shed. Some of these coppers have asudden depression in the bottom, into which the refuseof the blubber subsides when it is sufficiently boiled ;and at the elevation of a foot or eighteen inches abovethe bottom, (higher than the cavity usually occupied bythe refuse,) is a grating and conducting pipe, throughwhich, on turning a stop cock, the greater part of the oilin the copper is conveyed into an adjoining cooler.

On the same, or on a little lower level than that ofthe copper, is fixed a square or oblong back or cooler,built generally of wood, but sometimes of brick or stonelined with lead or cement, capable of containing fromten to twenty tons of oil or upwards. Adjoining to this isanother back, sometimes a third, and occasionally a fourthpr fifth, each placed a little lower than the one preceding■b so that the lowest shall stand with its base about two

°r three feet above the level of the ground. In somevery modern works, the coolers are all fixed at the sameelevation. Each of the backs is provided with one ormore stop-cocks on the most accessible side for conve-nience of drawing the oil off into casks.

Altogether above the level of the copper, and imme-diately adjoining it, on the side directed towards theriver or canal, an oblong wooden cistern, called thestarting back, is usually erected, for containing blubber,' v hich ought to be a vessel of equal or nearly equal ca-pacity to that of the copper. It is generally providedw *th a crane, which, with a winch, or other similar en-§me attached, is so contrived as to take casks, eitherrom the quay or from a lighter by the side of the quay,m>d convey them at once to the top of the starting back.Over this vessel is extended a kind of railing or gaun-

on which the casks rest, w'ithout being injured,

placed be-however, the fenks

tree

an d are easily movable.

The starting back being elevated two or three yardsab ove the level of the ground, occasionally admits of afink back or depository for the refuse of the blubberimmediately beneath it; which fenk back is sometimesProvided with a claugh on the side next to the water forparting- the fenks into a barge or lighterow> In some extensive premises.ar e deposited in a large shallow cistern or pit sunk intothe earth, and made sufficiently large to contaiu thewhole refuse of one car<ro; where it remains undisturbedwntil the action of the sun extracts the remaining oil andbn "f ^ to the surface. , r t

1 he premises likewise comprise a shea for the cooper,* nd sometimes a cooper’s or master boiler’s dwelling-house; the inhabitant of which takes the charge of allthe blubber, oil, whalebone, and other articles deposited

around him.

jv}7 are houses for containing the oil after it is drawn

; ln to casks are also used, not only for preserving it

n sate custody) but for defending the cas ks from the

7 s of the sun, otherwise they are apt to pine andbecome leaky.

pari° met 'vf eS a ^' J, ‘P ln S back and apparatus for pre-closure Wba ' e ^ one are comprised within the same en-

( 63 3.) Process of boiling..

-The blubber, which

originally in the state of firm fat, is found on arrival in Mechanicala warm climate to be in a great measure resolved into Processes,oil. The casks containing the blubber are conveyed, by ^

the mechanical apparatus above-mentioned, to the top, "ji e! j s "of the starting back, into which their contents areemptied or started, through the bungholes.

When the copper is properly cleansed, the contentsof the starting back, on lifting a claugh at the extremity,oi turning a stop-cock, fall directly into the copper, oneedge of which is usually placed beneath.

In the premises of William Mellish, Esq., ShadwellDocks, London , which are the best adapted of auvwhich Mr. Scoresby had seen, the starting back, which isabout ten tons in capacity, has a false bottom full ofsmall holes, placed a few inches above the true bottom,by which the oil is drained off, and passes through agrating and conducting pipe into an adjoining- copper,and is boiled by itself, while the fenks collected by thegrating are, at the same time, boiled in another copperplaced equally convenient.

The copper is filled within two or three inches of thetop, a little space being requisite to admit ot the expan-sion of the oil when heated; and then a brisk fire isapplied in the furnace and continued until the oil beginsto boil. This effect usually takes place in less than twohours. Many of the fritters or fenks float on the surfaceof the oil before it is heated, but after it is boiled off, thewhole, or nearly so, subsides to the bottom. From thetime the copper begins to \arm until it is boiled off orceases to boil, the contents must be incessantly stirredby means of a pole, armed with a kind of broad bluntchisel, to prevent the fenks from adhering to the bottomor sides of the vessel. When once the Contents of thecopper boil, the fire in the furnace is immediately re-duced, and shortly afterwards altogether withdrawn.

Some persons allow the copper to boil an hour, othersduring two or three hours. The former practice is sup-posed to produce finer and paler oil, the latter a greaterquantity. The same copper is usually boiled twice inevery twenty-four hours, Sundays excepted. Supposingthe copper to be filled at four in the morning, it isgenerally brought to boil by half-past five, and boiledoff at half-past six or seven. It then stands to cool orsubside until about two o’clock in the afternoon, whenthe boiling process commences. One of the backsor coolers having been prepared for the reception of oil,by putting into it a quantity of water, for the doublepurpose of preventing the heat of the oil from warpingor rending the back, and for receiving any impuritieswhich it may happen to hold in suspension, a woodenspout, with a large square box-like head, which head isfilled with brushwood or broom that it may act as afilter, is then placed along from the copper head tothe cooler, so as to form a communication between thetwo. The oil in the copper being now separated fromthe fenks, water, and other impurities, all of which havesubsided to the bottom, is, in a great measure, run offthrough the pipe communicating with the cociler, andthe remainder is carefully lifted in copper or tin ladles,and poured upon the broom in the spout, from whenceit runs into the same cooler, at the pleasure of theboilers. Besides oil and fenks, the blubber of thewhale likewise affords a considerable quantity of wateryliquor, produced probably from the putrescence of theblood, on the surface of which some of the fenks, andall the greasy animal matter called foolje or footing,float, and upon the top of these the oil. Great care,

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