This machine (Fig. 77) is of massive construction, suited to the very largest factories and the hardest work, and also of beautiful finish. The water is carbonated in a strong copper or gun-metal condenser, well tinned inside, which is made in two or three parts, with uniting gun-metal flanges secured by bolts. The agitator spindle passes through a stuffing-box at each end of the condenser, and the ends of the spindle are supported by suitable iron brackets, so as to relieve the stuffing boxes from pressure. Two complete pumps on the Bramah principle, each provided with regulating cocks for gas and water, are fixed in the frame, both of which are connected with the condenser.

The illustration, Fig. 78, shows a machine which is especially recommended where steam power is used. The design of the working parts is similar to the Bramah machine, but the condenser is of extra size, holding about 4 1/2 gallons, fitted with water-gauge; and the pump is 2 1/2 inches in diameter. The frame is of a design corresponding with the other larger machines, combining greatly increased strength and steadiness, with easy access to the pump, etc., and the whole is mounted on a strong cast-iron bed-plate, thus being suited for the heaviest work. The machine is fitted with fast-and loose driving pulleys, and will produce from 500 to 700 dozen a day of first-class soda water. The workmanship of these machines is of the very best quality.

"For many large factories," say the manufacturers, "among which we may especially mention a number of those of the Aerated Bread 13

Fig. 76.   Carbonating Machine with Two Cylinders

Fig. 76. - Carbonating Machine with Two Cylinders.

Fig. 77.   Horizontal Carbonating Cylinder with Double Pumps

Fig. 77. - Horizontal Carbonating Cylinder with Double Pumps.

Fig. 78.   Carbonating Machine with one Cylinder

Fig. 78. - Carbonating Machine with one Cylinder.

Company, London, we have made gas generators of wood. These are made of oak, very strongly hooped with copper and are very durable; as it is well known that when the sulphuric acid has charred the surface of wood its action does not penetrate further. The agitators are of gun metal on a strong copper centre bar, all strongly tinned, with gun-metal ends. The generator is fitted with all needful fittings as shown, and pulley for strap". (Fig. 79.) The trouble with wood generators in general is that they dry and warp on the upper part, and thus are subject to leakage, and so waste gas.

This machine (Fig. 80) is adapted for large factories, where steam power is used. The crank-shafts are of forged iron or of steel, turned out of the solid forgings; the pumps are of improved make, the framework throughout is massive, and the whole is mounted on a strong cast-iron bed-plate. The workmanship is a high-class engine work.

All these pumps are suited to work up to 200 pressure. The amount of carbonated water produced by these pumps differs according to the practice of various factories, but from observations it is stated they may be given as below:

Inch Pumps.

Doz. a day.

Pair of 2 1/2 . .

1000 to 1500

" 3 . .

2000 " 3000

" 3 1/2 . .

3000 " 3500

The driving gear can be arranged for disconnecting, so that each pump can be worked separately as a single machine, if desired. The manufacturers of these pumps are Hay-ward Tyler & Co., and Dows, Clark & Co., London.

Fig. 79.   Wooden Generator

Fig. 79. - Wooden Generator.

Fig. 80.   Double Pumps in Frames

Fig. 80. - Double Pumps in Frames.

There exists a demand in many factories for a class of pumps somewhat lighter and less highly finished than those shown in the sketch given, and yet of good materials and workmanship; the manufacturers have brought out a series of pumps in frames at very moderate prices. They are not mounted on bed-plate, but have strong, wrought-iron crank, fly-wheel, driving-pulleys, etc., and solution tank, and are well fitted throughout.

This whiting mixer will be found a very great advantage in all large factories where steam power is used. It ensures a more regular supply of gas, saves whiting, acid and labor, and will repay its cost in a very short time. The whiting and water are put in in measured quantities, and the mixer reduces the whole to an even paste of the proper consistency for the acid to act to the best advantage. Much loss of time and money is caused in some factories by accidents to the internal parts of the generators from hard lumps of whiting or insufficiency of water. All this is obviated by the use of this improvement.

Fig. 81.  Whiting Mixer

Fig. 81.- Whiting Mixer.

Fig. 82.   Gas Washer or Purifier

Fig. 82. - Gas Washer or Purifier.

Fig. 83.   Secttonal view of Fig. 82

Fig. 83. - Secttonal view of Fig. 82.

These gas washers or purifying apparatus are constructed of strong oak, well hooped, and provided with two or more perforated diaphragms. The fittings are of gun-metal, turned where necessary.

In the interior of the vessel are a succession of diaphragms pierced with small holes, and between the diaphragms are layers of suitable material, between which the gas can pass freely, but only in a succession of minute bubbles. Small pieces of marble are perhaps the best for this purpose, as, if any sulphuric acid is passing over into the gas, it is at once intercepted, and carbonic acid only sent forward. The vessel is filled with water within two or three inches of the top. A brass plug is provided at the side to show how high to fill the vessel. The gas enters the water at the bottom of the vessel, the pipe used for this purpose being made of glass, and in its upward course is broken up into a constaut succession of the most minute bubbles, so that no part of it can escape being washed. When it arrives at the surface of the water it passes off through a pipe of pure tin to the gas holder. The materials used are such as to insure the most perfect security possible from all contamination. The whole is so arranged that it can be readily taken to pieces for examination or cleaning, and easily set to work again without skilled labor. These gaswashers are adapted for the continuous plan only where no high pressure is exerted by the gas.

Fig. 84.   Gas Indicator and Washes

Fig. 84. - Gas Indicator and Washes.

Fig. 85.   Tinned Copper Supersaturator

Fig. 85. - Tinned Copper Supersaturator.