488

MANUFACTURES.

Manufac- wor ]{ S are a l so employed in the same manufacture inhues. p) ur ) lam anc j Northumberland. The process of formingthis salt in 1678 is described by D. Colwell, Esq., invol. xii. of the Philosophical Transactions , and it is ex-traordinary to find amongst the numerous changes whichthe Arts and the Manufactures of England have under-gone in this series of years, how little difference thereis in this one in particular. It is unnecessary to tran-scribe Mr. Colwell’s account, but by referring to it thereader will find how little it differs from the following,communicated to Dr. Aikin, as descriptive of the modernprocess.

The usual mode of manufacturing copperas on theRivers Tyne and Wear, is by exposing iron pyrites, (therecalled brasses,) which are found in the collieries, to theinfluence of the atmosphere. For this purpose, a situa-tion is chosen, inclining towards the river, of a naturalstrong clay. After the soil is taken off, gutters are cutin different directions, and wells of about five or six feetdeep and two or three in diameter are sunk where thegutters terminate. Upon this surface the brasses arelaid to the thickness of four or five feet. The vitrioliza-tion shows itself in a white efflorescence, which is washedoff by the rain into the gutters, and conveyed by pipesfrom the wells to a reservoir, from which there is a pipeof communication to the boiler. This is a leaden vesselgenerally about seven feet deep, twelve or fourteen long,and six or seven wide. Here the liquor is evaporatedfor six days, during which time as much of old ironis added to it as it will dissolve. It is then run into acrystallizing vessel, and remains there for five weeks,at the end of which time the mother-liquor is run intoa reservoir, and pumped back into the boiler, the crys-tals being removed, which after being drained arepacked in hogsheads for sale. A single boiling froma boiler of the above dimensions yields from five toeight tons of copperas, according to the strength of theliquor.

In 1830, an account was published in the Repertoryof Arts, vol. liv., describing the principles of a French patent for the manufacture of this salt, but we are notaware that any works founded upon it have been adoptedin this Country.

Vinegar Works.

Manufac- (631.) Vinegary / as,doubtless, asits nameimports, first

ture of made from wine, and is always so made in wine Coun-vinegar. tries. It is there prepared by adding wine lees to wine,

which excites a new fermentation that is kept up till thewhole is changed to vinegar; but in this Country vine-gar is generally made from malt, the usual process beingas follows.

A mash of malt and hot water is made, which, afterinfusion for an hour and a half, is conveyed into coolersa few inches deep, and thence, when sufficiently cooled,into large and deep fermenting tuns, in which it is mixedwith yeast, and kept in fermentation for four or five days.The liquor (which is now a strong ale without hops) isthen distributed into smaller barrels, set close togetherin a stoved chamber, and a moderate heat is kept up forabout six weeks, during which the fermentation goeson equally aud uniformly till the whole is soured. Thisis then emptied into common barrels, which are set inrows (often of many hundreds) in a field in the openair, the bunghole being just covered with a tile to keepoff the wet, but to allow a free admission of air. Here

the liquor remains for four or five months, according tothe heat of the weather, a gentle fermentation beingkept up till it becomes perfect vinegar. This is finishedin the following way. Large tuns are employed with afalse bottom, on which is put a quantity of the refuse ofraisins or other fruit left by the makers of raisin andother home-made wines, technically called rape. Theserape tuns are worked by pairs ; one of them is quitefilled with the vinegar from the barrels, aud the other isonly three-quarters full, so that the fet mentation is ex-cited more easily in the latter than in the former, andevery day a portion of the vinegar is laded from one tothe other till the whole is completely finished and fitfor sale.

Vinegar, as well as fruit wines, is often made insmall quantities for domestic uses, and the process is byno means difficult. The materials maybe either brownsugar and water alone, or sugar with raisins, currants,and especially ripe gooseberries. These should bemixed in the proportions which would give a strongwine put into a small barrel, which it should fill about three-fourths, and the bunghole should be very loosely stopped.Some yeast, or what is better, a toast sopped in yeastshould be put in, and the barrel set in the sun in sum-mer, or a little way from a fire in winter, and the fer-mentation will soon begin. This should be kept upconstant but very moderate, till the taste and smell indi-cate that the vinegar is complete. It should then bepoured off clear and bottled carefully, and it will keepmuch better if it is boiled for a minute, cooled and

Mechanic 8 !

Processes-

strained before bottling.

The following is the quantity of British vinegar madeand paying duty from 1820 to 1831 :

Number of

Amount of

Years.

Gallons.

Duty.

1820

2,497,468

£40,586

1821

2,754,004

43,802

1822

2,004,639

45,638

1823

2,406,563

47,124

1824

2,360,426

46,341

1825

2,340,812

45,518

1826

3,028,891

25,136

1827

2,967,864

24,746

1828

2,682,867

24,475

1829

2,558,798

22,541

1830

2,159,858

17,862

1831

2,689,747

19,313

Whale Oil Works.

(632.) Amongst the various objects of British manulac-ture, and resting on British enterprise, the whale fisheriesare by no means unimportant. The fishery itself is a sub-ject of great interest, and is described with great perspi-cuity by Mr. Scoresby, in his Account of the ArcticRegions, published in 1S20. It is, however, not withinour limits to enter into a description of this first P r0 S5 s ^towards obtaining the oil. We must consider the fisas already caught and stowed in the whale ships, anthat these have returned to port with their blubber obe converted into oil fit for use. For the followingdescription of this process we are indebted to vol. **•of Mr. Scoresby’s Work above referred to. Descrip 4 . 11 ^

Description of the premises, apparatus, fyc. Un 0 f pre* 1 * ,margin of a wet-dock, canal, or other sheet of water, com. and apPmunicating with that wherein the whale-fishing ship 1S us.charges her cargo, are usually provided the necessary