190 



EXPERIMENT STATION EECORD. 



The main features of tliis plant consist of a vaporizer surrounding the upper 

 portion of the generator, which can be removed for periodic cleaning when 

 using hard water : and of :i device for heating the air previous to its mixture 

 with the steam. The latter device consists of a spiral passageway located in 

 the outlet of the generator. The walls of the passage are highly heated by the 

 outtiowing gas, and the air in traversing the passage becomes correspondingly 

 hot, enabling it to carry along the requisite quantity of steam in suspension as 

 it enters the generator. A hand-operated fan is also provided to facilitate 

 starting. The gases are cleaned and cooled by being passed through an ordi- 

 nary coke scrubber, after which they pass directly to the engine. 



Test of producer gas engine plant at Toledo, Ohio (Gr^.s- E))[/iiie, 8 {1906). 

 No. 8, pp. 254-256). — Report of a test of gas engine and producer plant of 

 American design and manufacture. On test the fuel consumption was 0.84 lb. 

 of Pennsylvania pea anthracite coal per brake-horsepower hour, thus giving a 

 thermal efficiency of about 24 per cent. The same plant now in commercial 

 operation uses 1.14 lbs. of coal per brake-liorsepower per liour. The efficiency of 

 the producer alone was found to be about 9."] i)er cent. 



The use of alcohol as a fuel for gas engines, II. Diedericks {Intcrnut. Mar. 

 Engin.. 1906, pp. 263-270). — In this article the autlior gives a very complete 

 resume of the whole subject, his information being drawn largely from German 

 practice. He considers the fuel value and physical properties of alcohol, and 

 the details of the alcohol engine wherever they may be different from a gaso- 

 line or crude-oil engine. 



In the discussion of denaturizing agents for ethyl alcohol the following table 

 is given, showing the materials and their percentages as used in different coun- 

 tries : 



Denaturizinfi agents used in different eountries. 



With regard to benzol the author states that " from 10 to 40 per cent is some- 

 times employed, thus raising the heating value of the fuel and thus decreasing 

 the cost per heat unit." As to the rusting of the engine cylinder by the use of 

 alcohol, it is claimed that this may be obviated by greater care in securing a 

 proper mixture of air and alcohol and by using benzol as an additional safe- 

 guard. Several types of alcohol carbureters are illustrated and described, and 

 attention is called to the fact that a high degree of heating in the carbui-eter 

 is undesirable from the standpoint of capacity and because of danger of pre- 

 iguition. The best temperature for the carbureter is shown to be between 75 

 and 80° F. 



In discussing the efficiency and cost of operation of engines using different 

 explosive fuels, the author brings out certain facts not generally recognized. 



