734 KEPOET— 1889. 



•downwards through the fuel, the object being to prevent that near the grate bars 

 from becoming too dead and so escaping conversion. 



The ' Jermanofski ' system is similar to the Wilkinson, but a fixing chamber 

 filled with limestone is added, and it is claimed that some benefit is derived from 

 the arrangement, though the author has not been able to determine what it is, 

 except that a certain amount of carburetting is done in it. 



In the ' Meeze ' process the water-gas is also made independently, but the car- 

 buretting is performed in clay retorts, fitted with an internal, central, perforated 

 iron pipe, through which the oil and gas enter, or, the author believes, that the oil 

 only is now admitted, and its vapour mixes afterwards with the gas in the 

 hydraulic main. 



The ' Lowe ' process is typical of the ' generator-superheater ' class, and its value 

 may be judgied fi-om the number of patents that have been grafted on it, mostly 

 with a view to evasion, but a recent judicial decision has thoroughly established the 

 rights of the original inventor. 



The ' Granger-Collins ' process originated directly in the Lowe, where the 

 generator and superheater, were connected by an iron pipe which acted ingeniously 

 as a cooler. Messrs. Granger and Go. shortened this connection and lined it with fire- 

 brick, but finally suppressed it altogether by making the superheater partly overlap 

 the generator, and thus secured direct communication without sacrificing the facilities 

 of stoking from above. The oil, also, was introduced by an injector or sprayer, so 

 that it met the water-gas coming over from the regenerator. Messrs. Granger and 

 Co. were the first, or among the first, builders of water-gas plant to appreciate the 

 necessity of making the superheater of ample size, and their installations have 

 achieved a deserved popularity. 



The ' Springer ' apparatus, constructed by the National Gas Light and Fuel 

 Company, of Chicago, encloses the generator and superheater in one shell, the two 

 chambers being separated by a firebrick arch, the fuel being introduced into the 

 lower by lateral furnace doors. The combined generator and superheater attains to a 

 very large size, more than 12 feet diameter by 50 feet high, with a producing 

 capacity of one million cubic feet per twenty-four hours. The steam in this plant 

 can also be passed up or down through the fuel, and the oil is introduced either at 

 the bottom or the top of the superheater, by means of a steam injector. 



The ' McKay-Critchlow ' apparatus is similar to the Springer, but is especially 

 designed for use with natural gas, which is introduced under the grate bars with 

 the steam. It becomes split up and carburets the manufactured gas. Natural gas 

 alone has feeble and irregular illuminating power, and is very flabby and unsteady. 

 The ' Flannery ' apparatus and the ' JFIanlon-Teadley ' do not differ essentially 

 from the types which have been described already, and it is doubtful whether the 

 alleged improvements have any substantial advantages. The last named has been 

 introduced into Philadelphia on a very large scale, and professes to supply gas at 

 the rate of 37 cents per thousand cubic feet. 



The ' Lowe ' process is now in the hands of the United Gas Improvement Com- 

 pany of Philadelphia, who are the largest manufacturers and owners of gas plant 

 in the States. The apparatus, as may be gathered from what has been already 

 said, has undergone many modifications at the hands of licensees ; especial atten- 

 tion has been directed to the manner of supplying the oil, which has increased in 

 importance since the serious rise in the price of naphtha has driven the gas-makers to 

 resort to crude oil. The United Gas Improvement Company now always heats the 

 oil before introducing it into the generator, and this is done by preference at the 

 expense of the waste heat in the gas passing from the superheater, but pre- 

 cautions have to be taken for preventing the formation of lamp-black inside the 

 pipes, or for removing it when formed, and with this view several varieties of 

 heaters are in use. The oil is pumped from a measuring tank through the heater 

 and introduced into the generator through four fire-cla}^ pipes which pass obliquely 

 through the arch forming its top, and are arranged to slide back during the time 

 that the ' blowing-up ' is in action. The author devoted a considerable space 

 to discussing the details of working, and pointed out very clearly what are the 

 conditions to be observed in order to ensure the most advantageous results. 



