Vinegar is cooling, opening, excites the appetite, assists digestion, is good for hot stomachs, resists putrefaction, and therefore very good against pestilential diseases. Too much use of it injures the nerves, emaciates some constitutions, is hurtful to the breast, and makes people look old and withered, with pale lips.

The best vinegar is that which is made of the best wines. Lemon-juice and verjuice have much the same qualities and effects as vinegar.

The commonest vinegar is least adulterated.

This is an acid liquor, prepared by a second fermentation from various liquors, such as wine, cider, perry, beer, mead, skimmed milk, etc. But the most common method of making it, in England, is from malt, and the process is as follows: - infuse a quantity of malt in hot water for an hour and a half, then pour it into a cooler. As soon as the infusion is sufficiently cold, put. it into deep tuns, add yeast to it, and leave it to ferment for four or five days; after which put the liquor into barrels, in a room heated with stoves,so that a moderate warmth may be kept up for six weeks, and the fermentation continue regularly. By the end of that time the whole will be completely soured, and must now be changed into other barrels; lay a tile on the bung-holes to keep out the wet, but not so (dose as to prevent a free circulation of air, and then place them in the open air for four or five months, according as the weather is warm or otherwise; during the whole of this period, the fermentation proceeds, and at the end, the vinegar is nearly done. The next operation is this: the vinegar is poured into large vessels, called rapetuns, to which these ate false bottoms cov-ered with rape, that is, the refuse of raisins, or other fruit, from which wine has been made; fill one of these tuns entirely with the vinegar, and another about three-fourths full, and every day take a portion of the liquor out of the fullest barrel, and put it into the other, until, the vinegar is in a fit state to be drawn oft"; when it must be closely barrelled.

Vinegar may also be made in much smaller quantities for domestic purposes; the materials of various kinds, with the addition of sugar; raisins, currants, and ripe gooseberries, however, are the principal; sometimes it is made from brown sugar, and water alone. T'he proportions are the same as those necessary for strong wine; make the barrel about three-fourths full, add a toast covered with yeast, put in the bung very loosely, and place the barrel where it will be exposed to the sun, or, if it be winter, near the fire. The fermentation should be moderate and constant till the vinegar is complete; then draw it off clear, give it a boil, and when quite cold, strain and bottle it.

Vinegar is obtained from wine, by mixing with the latter its own flowers, or ferment, and its tartar reduced to powder, and put into a vinegar or any other cask; if the latter, it must be placed in a warm situation, full of the steam from vinegar; in either case the liquor should be stirred frequently; the second fermentation will speedily commence; it will become heated, and turn acid by degrees, and in a short time the vinegar will be produced.

It is commonly supposed that wine which has become acid, will produce excellent vinegar; this, however, is a mistaken idea, for the stronger and better the quality of the wine, the stronger and better will be the vinegar.

The French have several methods of making vinegar, which are subjoined.

The vinegar makers of Orleans pour the wine, of which they intend to make their vinegar, into casks, at the bottoms of which are close gratings of lime twigs; these serve to clarify the wine, as the lees adhering to the twigs, leave the liquor perfectly clear. They then procure a number of casks, each containing a hundred gallons, either new or which have previously contained vinegar; these are set upright, and in the top of every one is bored a hole, two inches in diameter, these are kept constantly open: the last mentioned casks are called Mothers; pour into all of them twenty-five gallons of boiling vinegar; to this, in a week's time, add three gallons of wine, drawn from the first mentioned casks; continue to add the wine, at intervals of a week, until the Mothers are quite full; then leave them for a fortnight, and at the end of which period they generally draw off the vinegar, taking care always to leave the Mothers half full, at least, and then to fill them with wine as before. The. method of proving when the vinegar is fit for use, is, by plunging a stave into it; if on taking it out, a white line is perceptible on the end of it, the vinegar is quite ready. The place where the casks are kept should be very airy, and in the winter time, by means of stoves the temperature should be raised to eighteen degrees of Reaumur.

Paris vinegar varies from the above, and the process is very simple. A large quantity of wine lees is put into coarse sacks, and laid in tubs, which are placed one upon another to form a kind of press; by means of a screw, every drop of wine is gradually squeezed from the lees; this operation cannot be performed in less time than a week. The wine thus extracted is put into casks; in the headings a hole is made, as above, which holes are left constantly open; in summer time the casks so filled are placed in the sun, and, generally speaking, the vinegar is fit for use in a fortnight. In the winter, the fermentation will last double the time, and must be assisted by artificial warmth. It sometimes happens that the liquor heats to so great a degree that the hand cannot be borne in it; in this case, the progress of the fermentation must be checked by adding more wine, until it proceeds more regularly. When the vinegar is made, put it into casks, which have the beech twigs at the bottom, as above mentioned; let it remain a fortnight, by which time it will be sufficiently fermented to draw off into the casks for keeping it.

Another very simple method is also practiced in France; a few quarts are drawn from a barrel of excellent vinegar, and an equal quantity of very clear white wine is put into the barrel, close the bung lightly, and keep it in a place where the heat is moderate and regular. In a month's time draw off the same quantity as above, and pour in an equal portion of white wine. A barrel of good vinegar will thus afford a constant supply for a length of time without leaving the slightest deposit.

A cask which has not contained vinegar before, should have a quart of boiling hot vinegar poured into it, shaken till cold, and allowed to stand for some hours.