plant, the cells of which multiply with incredible rapidity, fermentation is set up, the chemical effect of which is to convert the sugar contained in the "wort," into carbonic acid and alcohol.

The brewer takes care, however, to stop the fermentation at a certain stage, so that a portion of the sugar may remain unconverted, and the chemical change is then completed in the cask or bottle, the carbonic acid being held in solution until the beer is drawn or otherwise exposed to atmospheric action. This gives to good beer its brisk sparkling appearance and puts a head upon it: in no case is the effect so conspicuous as in the bottled German beer and English and Scotch pale ales, which continue to effervesce and sparkle like champagne, long after the liquid is poured into a tumbler.

Passing now from the theory to the practice of brewing, I propose to conduct my readers through some portions of the magnificent establishment of Messrs. Allsopp and Sons, of Burton-on-Trent, where all that science and skill can accomplish has been done to perfect the process. Let us commence with the malting; and the reader must imagine himself in a large chamber (one of several devoted to this purpose), one end of which is partitioned off for the steeping process. This side of the room, which forms an elongated trough, is divided into squares, and partly floored with a number of perforated tiles, which serve to drain off the water; and when the barley is sufficiently steeped, it is turned out upon the chamber floor, close to the trough. Here it is kept within certain limits, by means of a removable partition consisting of boards, which can be fixed between the columns that run across the chamber parallel to the steeping-trough, or removed at pleasure; and the barley is then said to be in the "couch," where it is gauged by the Excise. After gauging, the partitions are removed and the steeped barley is spread evenly over the chamber floor to germinate: the germination having reached the proper stage (as already described), it is conveyed to the kiln to dry. But at Allsopps' the transfer of the barley from the germinating floor to the kiln is only the passage from one chamber to another immediately adjoining; and unless his attention is directed to the floor, the uninitiated visitor would observe nothing in this second chamber to denote its function. The floor is paved with perforated tiles, and in the kiln pit underneath, which is the same size as the upper chamber, there stand a series of open furnaces, or gigantic braziers, in which coke fires are lighted when the kiln is in use. Over the fires there is a contrivance called a disperser, by which the heat rising from these furnaces is equalized over the whole surface; and when the spectator looks up at this disperser, he perceives plainly the perforations in the tiles of the kiln floor above, and which allow the heat to penetrate to the malt. After kiln-drying, the barley, or as it is then called, malt, is subjected to one more process, namely, screening. This consists in allowing it to run over an ob

lique screen, and during its passage the malt dust and radicles are removed. These make an excellent food for cattle, varying in value from 51. to 77. per ton, according to the requirements of the season.

This completes the malting process; and now we pass on to the brewing, which commences with the grinding of the malt. By means of a "Jacob's ladder," it is conveyed to an upper story, and there allowed to fall into a hopper, which feeds a pair of smooth rollers, very similar to those used in an oil mill for rolling linseed. Being thus split, and partially ground, it is carried along the chamber floor by means of an Archimedian screw, and passed through a hole in the floor into a large hopper in the story below. This hopper is fixed above the "mash-tun," or "mash-tub," where the ground malt is mixed with water at a temperature of 170° to 180°, and undergoes the mashing process. The room in which we are now supposed to stand contains eight such tubs, each capable of treating fifty quarters of malt, and two of them are shown in Plate II., the one closed and the other open. I was, unfortunately, unable to obtain a sketch, which would fully illustrate the mashing process, but will endeavour to make it as clear as possible with the means at my command.* The mash-tun has a false bottom, composed of radiating sections, the object of this being to take them out to clean after each mashing. Then there revolve in the tub two kinds of apparatus, the one for mashing," the other for "sparging," to be explained presently. An upright spindle revolves in the centre of the tun; and rotating with it, is a strong horizontal wooden pole, having one end affixed to the central spindle, and the other end, to which a cog-wheel is attached, resting upon rack-work that runs completely round the inside of the tun. The arrangement will be better understood if the reader pictures to himself one of those "roundabouts," on which children ride at fairs, with the horizontal pole resting on rack-work, which is visible in the plate. Along the rotating horizontal pole there are placed several beaters, somewhat resembling the rakes upon a reaping machine, but armed with teeth on either side. I have sketched (Fig. 9)

66

FIG. 9.

one of these beaters with a portion of the horizontal pole, and by a suitable mechanism the beaters are made to revolve vertically in the

* All the page plates are copied from photographs kindly lent me by the Messrs. Allsopp.

mash, whilst the pole to which they are attached rotates horizontally, so that the whole contents of the tun are thoroughly beaten and mixed. This operation has really a very novel and interesting appearance to one who has never witnessed it before. As the observer stands looking into one of the openings in the mash-tun, nothing appears to be going on in the mash so long as the beaters are on the side opposite to him, but presently a slight undulation of the surface announces their approach. Slowly the pole, with its beaters, moves round towards the side where the spectator stands; the undulations become more marked, until at length the revolving arms make their appearance, breaking up the surface and creating a great commotion. After the round is completed, the apparatus is stopped, and the mash is left undisturbed for some time, the process being repeated at regular intervals. But there is another rotating apparatus of a very simple kind attached to the central spindle, and that resembles in appearance and action the horizontal discharge-pipe at the back of a watering cart. It is in fact a copper pipe, of a suitable shape, with holes drilled along its whole length, and may be seen on looking through one of the openings in the mash-tun (see Plate II.). After the strongest portion of the "wort " is obtained from the malt by the mashing process already described, it is dosed with a shower of hot water, poured upon it from this rotating pipe, which is called the "sparge," the operation being termed "sparging." At the bottom of each mash-tun there are four pipes through which the wort is drawn off, and these pipes lead into a main which conducts the liquid into the "underback," an intermediate vessel between the mashtun and the boiling copper, where, as the name indicates, the process of boiling with hops is carried on.

The boiler is an open copper cauldron or kettle, set in brick, and heated from beneath. It has a capacity of about seventy barrels; and when the requisite quantity of hops is deposited in it, the wort is admitted through a pipe connected with the "underback," into which the liquor has been run from the mash-tun, as already described. The feed-pipe bends over the opening of the copper, whilst at the bottom of the same vessel is another pipe, through which, when the boiling is complete (and the liquor is well stirred during the process), the boiled wort, or unfermented beer, is run off into the "hop-backs." These, again, are intermediate vessels, square wooden cisterns, with false bottoms, which act as a sieve, and the object of running the liquor into them is to free it from the spent hops with which it is accompanied, before cooling and fermentation.

A word concerning the spent hops. After the liquor has been allowed to drain from them in the hop-backs, they are placed in hydraulic presses to extract any wort that may still remain in them, and are then packed and sold as manure.

From the "hop-backs" the wort runs into the refrigerators,