TRANSACTIONS OF SECTION G. 733 



uninterruptedly, or a cupola furnace is employed, and steam and air are forced in 

 continuously, but the latter process has the disadvantage of the resultant giisea 

 being associated with a great deal of nitrogen, so that after enrichment with hydro- 

 carbons the flame is ' tender,' it is easily blown out, and smokes on small provoca- 

 tion. 



The author stated that Fontana first proposed the manufacture of water- 

 gas in 1780, and he traced the history of the invention through its successive 

 stages of improvement to the present day ; he enumerated the large number of 

 patents, which amount in the aggregate to 100, that have been taken out since 

 1823; he summarised the merits and defects of each, and closed his sketch 

 by alluding to the battles fought in the United States between the coal-gas 

 and the water-gas interests, the question of the danger of the latter being the 

 main point at issue. The professional papers ranged themselves on opposite 

 sides, and courts of law had to decide between the conflicting evidence of experts. 

 The old Boston Gas Company succeeded in obtaining the passage of a law prohibit- 

 ing, in the State of Massachusetts, the manufacture and sale of gas containing 

 more than 10 per cent, of carbonic oxide, this rendered it impossible to manufac- 

 ture water-gas economically. Litigation of an energetic character went on for 

 years, and, indeed, is still raging, though 223 Boston doctors have signed their 

 names to a declaration ' that water-gas is no more dangerous to health and life than 

 coal-gas, and there is no just ground, so far as health and life are concerned, to 

 prohibit its manufacture.' This opinion has been endorsed by numerous chemists 

 of eminence, both in the United States and in Europe. 



In 1874 there was practically no water-gas made in the United States or in 

 Canada. It is estimated that at the present day, out of 1,150 gasworks, 300 are 

 on the water-gas system. 



With the quantity of gas produced the quality has improved greatly, so that 

 there is now probably no gas better adapted for distribution in extremely cold 

 climates than a water-gas made in a modern plant of certain construction, and 

 that, too, from ordinary furnace coal, gas coke, and crude oil. 



The author next proceeded to consider the theory of the process in detail, and 

 calculated the distribution of heat throughout the reactions, remarking that it is 

 only by the application of the water-gas system of manufacture that the whole of 

 the carbon used can be converted into gas. 



The following details are included in most of the plants constructed on the inter- 

 mittent system. An upright furnace of the cupola type is used both for combustion 

 and for gasification. This is called the ' generator,' or ' gasogene,' to supply whinh 

 Bteam is generated in an independent boiler, and the steam is sometimes super- 

 heated either by the fire of the regenerator, or by waste heat. 



In one class of apparatus the generator is provided with two outlets, one of 

 which is connected to the chimney, and the other to the wash-box, or hydraulic 

 seal, both outlets being controlled by valves. In another class the generator is 

 connected to a separate superheater, or fixing chamber, which is provided with the 

 two outlets, as described above. The fixing chamber is filled with refractory mate- 

 rial, and is intended to store up heat during the ' blows,' which heat is to be used 

 in the ' run ' for fixing or rendering permanent the hydrocarbon gases added to 

 the water-gas. In both cases the gas is condensed, scrubbed, purified, and mea- 

 sured in the same way as ordinary coal-gas. 



In the ' Tessie de Motay ' or ' Municipal ' process the products of combustion 

 and heat during the ' blows ' are lost up the chimney. 1 he water-gas goes to a 

 crude-gas holder, from which it is passed to the carburetters, which consist of a 

 number of shallow pans, containing naphtha, over the surface of which the gas 

 passes, the temperature being carefully regulated. The mechanical mixture of gas 

 and naphtha vapour is then fixed by being passed through retorts arranged in 

 benches and sometimes fitted with baflers. Means are provided for easily testing 

 the gas, which can be produced of a very even and beautiful quality. This process, 

 though wasteful, has met with marked success for several reasons, which were given. 



The ' WilkinBon ' process is similar to the one just described, the chief point of 

 difference being the admission of steam to the generator alternately, upwards and 



