Fig. 119.   German Plan of Continuous Apparatus   i

Fig. 119. - German Plan of Continuous Apparatus - i.

As will be readily seen, one ends in the inside of purifier in an extra perforated cylinder a, the other one in a perforated tube b, and the interior of purifier contains three perforated chambers a a a, which cause the carbonic acid gas to rise in minute division.

In the gasometer the tube q that leads the gas over from purifiers ends above the surface of the liquid, thus not utilizing this water for purification of the gas. Frequently both the tube leading the gas in and the other leading it out to the pump enter on top of the bell at a suitable coupling. In this case part of both tubes are of good rubber so the tubes may follow the movements of the gasometer-bell. It is claimed that when the gas tubes enter from beneath, very frequently some water in gaseous or other form is carried up into the bell, there condensed, and falling into the tube, collects there, and especially in winter time freezing, clogging or bursting of the tubes may occur. This disadvantage can be overcome by passing both tubes through top of the bell.

There is no objection to the latter arrangement, however, where none or not many purifiers are used and the tank water in gasometer is looked upon as washing-liquid; the tube should end from beneath, and when securely fastened, the liquid frequently renewed and the necessary care being taken, there will be no trouble. A practical improvement on gasometers would be an attachment to indicate the contents of the bell.

Fig. 120.   Purifying Cylinder

Fig. 120. - Purifying Cylinder.

Fig. 121.   Another Purifying Cylinder

Fig. 121. - Another Purifying Cylinder.

The pump with ball-valves is described with the French apparatus. The same kind is used in connection with German carbonating machines. The valves of those pumps gradually wear out and get loose. A practical pump in use is illustrated on the next page.

A is the cylinder of brass. B, the piston with leather collar, led vertically by rod C and cover D. F is the suction-valve which rests on valve e e, that is renewed when worn out. On raising the piston B, the valve F is lifted, but by the gravity of its own weight and spring g, falls quickly back as soon as the stroke ceases and then rests on e e horizontally. The pressure-valve H is kept closed by spiral spring K, and opens on the downward stroke of the piston by the pressure of the compressed gas overcoming the resistance of spring K, the compressed gas escaping through pipe l and spring k closing the valve again as soon as the downward stroke of piston B is interrupted. Suction-pipe S S leads either gas or water, or both together, into the pump and in any quantities according to the adjustment of the cock illustrated here. The motive power of the pump is either steam or hand.

Double pumps are attached to large sets of apparatus, generally with horizontal double cylinders, the pistons of which alternately draw on one side and compress on the other. Pump-cylinders, solely drawing gas, are surrounded by a water-tank of the same height. The strong compression of the gas in connection with the warmth produced by friction, causes a remarkable heating of the pump and needs cooling. The water has to be frequently renewed by a cold supply. Pumps moved by hand need it not so frequently as when steam-power is used. The pump is one of the most important parts of the apparatus and should be carefully treated.

Fig. 122.   Sectional View of German Pump

Fig. 122. - Sectional View of German Pump.

Fig. 123.   Indicator Cock

Fig. 123. - Indicator Cock.

The condenser and agitator are constructed on the already described principles, also pressure-gauge and safety-valve.

A mixer for salt solutions as already described is frequently adjusted on top of the condenser, or a coupling arranged to screw the mixer on when needed.

Oberdoerffer & Zinkeisen of Hamburg construct an apparatus after the English plan as represented in the following illustration.

The principles of construction are similar to those already described 15 under the English plan to which we refer. The generator is adjusted with an acid bottle on top with regulating valve.

The apparatus, with large cylindrical condenser, arranged either for continuous or semi-continuous use, is much more preferred in Germany than the apparatus with the globular condenser. Where large quantities of mineral waters are made, the cylindrical condenser for semi-continuous action is exclusively in use.

Fig. 124.   German Plan of Continuous Apparatus   II

Fig. 124. - German Plan of Continuous Apparatus - II.

Fig. 125.   German Plan of Continuous Apparatus   III

Fig. 125. - German Plan of Continuous Apparatus - III.

This apparatus (Fig. 125) is constructed quite differently from the others. The generator rests vertically on an iron support. To the large iron frame are secured two cylinders f. The first and smaller one serves for purifying the gas, and is for this purpose divided in several compartments. The larger cylinder is for impregnation. The whole construction is explained by the illustration. The fountains are either of iron and enameled inside, or of copper and well tinned.

Fountains of glass are a decided novelty. We have known of glass-lined fountains, but the illustration in Fig. 126 represents a stationary fountain, the principal body of which is entirely made of glass. This apparatus as well as the last-described one is patented by N. Gressler in Halle a. S., Germany.

The glass fountains are made of very stout glass, in the same shape and size as the iron or copper fountains. The two metallic heads are securely bolted together and either enameled or tin-lined inside. The agitator, of iron, is either enameled or also tin-lined.

They permit a pressure of 4 atmospheres (60 pounds), and are especially adapted for mineral waters or other sparkling beverages where no higher pressure is required. Glass fountains for up to 12 atmospheres pressure (190 pounds), however, are made also; but this kind is surrounded by a strong copper cylinder, and so constructed that between the copper and glass cylinder is a free space which serves for cooling purposes. When charging the apparatus a special arrangement provides that the pressure within this glass fountain and outside, between the latter and the copper cylinder, is equal. Water- and pressure-gauges are attached.