the boiler furnished steam of 22 kilogrammes (5.5 lbs.) pressure per square centimeter (0.155 square inch) to an engine which kept all the machinery of the works moving. The apparatus requires but little attention. By regulating the supply of oil and steam the flame can be immediately augmented or decreased.

H. de Bay and Ch. de Rosette's sprinkler. De Bay and de Rosette of Paris propose (German patent No. 31,962) to introduce the oil by compressed air or steam into a retort which is heated by the fire itself. For this purpose the oil runs from the holder A, Fig. 211, together with compressed air admitted through the nozzle a, into the retort C. The gases produced pass through D into a holder E. A stronger current of com

pressed air enters the holder E through the pipe F and carries the gases through the filtering pipes m and n to be burned for heating the boiler as well as the retort C. This effect is claimed to become still more perfect by placing pipes G, Fig. 212, which contain barium, potassium permanganate or other substances readily yielding oxygen, in the firebox. A current of compressed air enters these pipes, becomes heated during its passage through them, absorbs the oxygen evolved, and passes into the fire-box through the pipe x. By the entrance of this current of air rich in oxygen, combustion is claimed to be

made more complete and the flame forced more towards the front portions of the grate, so that no combustible substances can reach the chimney. The grate is covered with one or more plates H, upon which is placed a layer of sulphate of line or barium to prevent cold air from penetrating through the bars of the grate.

F. Morth's Sprinkler. A mixture of hydrocarbons and superheated steam is introduced into the fire-box of a boiler by means of a net-work of pipes B, provided with holes m, Fig. 213, and a pipe C also provided with holes n, placed in the front part of the fire-box. For the purpose of regulating the supply of gas-mixture, a nozzle q, provided with screw threads, is placed on the end of the injector A, Fig. 214, at the mouth

of the chamber h and a nozzle q' of similar shape at the mouth of the chamber h'.

Körting's Tar Sprinkler. This sprinkler is constructed of

iron, and essentially consists of a pipe from the front end of which the tar issues in a thin layer to be atomized by a jet of steam striking it at an adequate angle. It is then mixed with atmospheric air and conducted to the combustion chamber.

FIG. 215.

The steam issues in a very peculiar manner, the effect being

that not a trace of tar can fall down. The supply of tar is regulated by the nozzle A, Fig. 215, the bore of which may be

larger or smaller according to requirement. By the pot T and the sieve S in it all impurities are retained, so that the nozzle A can clog up only under peculiar conditions. To be able to clean it in such case without taking the apparatus apart, it is only necessary to push back the case H and clean the nozzle A with a needle. In case the actual pulverizer F should become choked up, it can be immediately cleaned, while working, by means of the needle R, after removing the lid V.

The pulverizer Z is placed by means of a short nozzle in an

opening in the furnace wall. The jet of steam, as mentioned above, sucks with great energy the air for combustion through this air nozzle, thus essentially assisting the attainment of perfect combustion. Combustion is regulated by the steam-pipe D, and slides on the side of the pulverizer, which can be so

arranged that only sufficient air to effect combustion without smoke is admitted.

In gas-houses the tar holder is placed upon the retort furnace, Fig. 216, to keep the tar warm and thinly fluid.

Of great importance in tar-firing is a continuous supply of tar, so that combustion is not interrupted. It is therefore recommended to place a second holder S upon the furnace, and connect it also with the pulverizer. From each holder a separate conduit, about 1 inch in diameter, leads close up to the pulverizer, and each nozzle for regulating the supply is provided with a stop-cock, so that the tar may be taken from either of the conduits as desired. With the use of furnaces, in which the lowest retort lies in the centre of the furnace, the pulverizer should be placed as low down as possible, so that the very hot flame cannot act directly upon the lowest retort. With furnaces in which the retorts lie on both sides, and in two rows, and above them in the centre, a fifth or seventh retort, the pulverizer may be placed at the ordinary height of the firebox.

At the present time Körting's sprinkler is also used for oil firing.

Drory's Tar and Oil Sprinkler.-The object of H. J. Drory's apparatus for tar and oil is to effect as complete com

bustion as possible, without smoke, of the liquid fuel supplied at fixed intervals. The nozzle D, Fig. 217, sits in a circular iron frame with a straight upper surface, which is provided with two apparatuses A and B. The liquid fuel is brought into A, while B serves for supplying previously heated compressed air, or dry steam. The tar or oil is then