Much has been said of the qualities of different kinds of water for the purposes of brewing, and writers in general have recommended soft water as preferable to hard. The latter is said to be less inclined to fermen tation, and therefore the beer will have less spirit than if made of soft ; but, it is more easy to brew transpa rent liquor from hard water, and it is not so liable to turn sour. Soft water, procured from rivers, often imbibes a great proportion of vegetable extract, and is then so liable to fermentation as frequently to become sour. As we see a general change in the system of the London brewers, from using soft river water, to hard spring water, it is presumptive proof, that the very purity and transparency of the water is of greater consequence than its hardness or softness; and the knowledge of this fact may induce brewers in other situations to place less de pendence upon the nature of their water, but to endea vour, by varying the management of their processes, to produce any kind of liquor from any water, (hard or soft,) provided it is clear, sweet, and free from mineral taints.
Brewing Utensils.
Ix describing the different utensils and vessels em ployed in a brewery, the mechanism used in the ope ration of mashing comes first to be considered. The mash tun is usually a large wooden tun, formed of ver tical staves bound by iron hoops, as shewn in Fig. 2, of Plate LXXVIII. It hasa false bottom placed a few in ches above the real bottom This is pierced with a great number of small holes, to admit the liquor, but retain the malt, which lies upon it as a floor. The li quor is brought by a pipe into the tun beneath the false bottom, and forces its way up through the goods (malt); and when it appears above them, the goods are stirred up, to expose every part of them to the action of the liquor. This was at one time performed by men, first using long rakes to level the heaps of malt, and after wards rowing the goods with large oars; but the great scale on which the breweries in London are now con ducted, renders this method inadmissible, from the num ber of men it would require. Mashing machines have therefore been generally adopted within the last 20 years, in all the great breweries. A number of different constructions are in use, and seem to answer their pur poses well ; but as the greatest number have been erect ed by Mr. Cooper, Old Street, London, we have pro cured a drawing of one of his construction. The mash tun and underback for this machine are wholly formed of cast iron, to avoid the continual and expensive re pairs, which wooden vessels of such large dimensions require. The machine in question was erected in 1809, at Messrs Barclay and Perkin's brewery, Southwark ; and the iron tun by Mr Jonathan Dickson, who has a patent for methods of forming various large brewing vessels in cast iron.
Piste LXXVIII. Fig. 1. is a plan of the mash tun, and Fig. 2, an elevation of it ; shewing also the under back beneath it ; one half of the mash tun being repre sented in section, to show the machine within it. AA, Fig. 2, is the level of the stage or floor in which the mash tun is placed. BBBB is the tun, formed of a num ber of pannels of cast iron plates screwed together.
The disposition of these in the bottom is shewn by the plans in Fig. I. The tun is supported upon 8 cast iron columns DI), which are united at the upper ends by an iron framing F., which confines them in a vertical posi tion, and connects them with a central column F. shewn by dotted lines in Fig. 2. at the upper end. This is cast hollow, to form the continuation of a pipe G, which brings the liquor into the tun from the copper. This pipe has also another branch II, conveying the liquor up into the tun, beneath the false bottom I, which is the only part of this machine made of wood. In the centre of the tun a vertical axis X is set up and turned round by wheelwork communicating with the upper end of it, as shewn in Fig. 3. Upon this axis are two bevelled wheels a and b, giving motion to the mashing engine. These wheels turn two horizontal axes L, M, extending from the centre to the circumference of the tun. The 'Omer has 4 wheels upon it, over which puss 4 endless chains, which also pass round wheels upon a horizontal axis N near the bottom of the tun. Upon the endless chain cross pieces of iron d are fixed ; and these have teeth in them, (as is shewn in the elevation, and on a larger scale in Fig. 5.) which, as the chains revolve by the action of the wheel b, raise up the malt from the bottom of the tun to the top of the mass of malt. That this stirring may be performed in all parts of the tun, the frame containing the axes L, M, N, has a progres sive motion round the tun, by the following means: On the kirb or upper edge of the tun, is a ring of teeth 00, shewn in the pian. These are engaged by an endless screw, which is mounted in a frame P, and shewn in perspective in Fig. 9. This screw has a rotatory mo tion, given it by a wheel Q on the extreme end of the axis Al, which turns pinions d, e, on the axes of the screw. The wheel has two rings of cogs k and 1 upon its face, one about Ids the size of the other Each en gages its pinion d and r on the spindac of the screw ; neither of which are fixed to this spindle, but, are at li berty to slip freely round it. Between the pinions, is a circular plate k fitted upon the axis with a filet, so that it must revolve with it. l'his pate has studs projecting from both sides, and the pinions have similar studs. Now when the plate k isilzust towards either of the pinions by means of a lever 1, it causes the axis and screw to revolve with the same velocity that the pinion has ; and as the pinions have different velocities, from being turned by two different rings of teeth, it follows, that by raising or depressing the end in of the lever /, the screw may be turned with either of these velocities at pleasure, and thus cause the machine to make the circuit of the tun in a greater or less time. The ex treme ends of the two axes L, N, are supported in an iron arm X, (see Fig. 4 ) fixed to the iron frame P of the screw, which runs upon the edge of the tun with four rollers. From this frame two rods ft 12, (Fig. 1.) extend to a frame shewn in fig. 3, which surrounds the central axis, and supports the central axis by a collar at its upper end, and the lower point of the axis is fitted into a socket made through the frame.