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The Philippine Journal of Science 



excelsior. The perforations are such as 

 to facilitate aggregation of moisture par- 

 ticles, and the water that collects on the 

 plates trickles into the excelsior. The ap- 

 paratus is incased in a chamber, which 

 has a removable cover and a water-sealed 

 drain for discharging the water that is 

 separated from the gas. After this treat- 

 ment the gas is passed through a small 

 gas holder. The diameter of the gas 

 holder is greater than the supply pipe, 

 and the pressure and velocity of the 

 gas are considerably reduced in passing 

 through it. This variation in pressure 

 and velocity causes a further deposition 

 of water, which from time to time is 

 blown off through a drain cock in the 

 bottom of the holder. Finally the gas 

 is passed through the last separator, 

 consisting of six baffles, constructed in 

 such a way as to reverse the direction 

 of the flow of the gas six times and 

 practically to eliminate any moisture or 

 tar that is still carried in the gas. This 

 is the final purification, and the gas is 

 delivered into the mixing chamber of the 

 gas engine. The gas holder distributes 

 the effect of the engine suction so as to 

 produce a steady supply of gas to the 

 engine. 



Gas engine. — The action of the 4-stroke cycle 

 engine driven by the gas is as follows: 



1. Suction or first stroke, which begins as 

 soon as the piston leaves its position nearest the 

 cylinder head and which ends when it reaches 

 its position nearest the crank. During this in- 

 terval the suction valve is open, while the ex- 

 haust valve is closed. 



2. Compression or second stroke, which begins 

 as soon as the piston leaves its position nearest 

 the crank and which ends when it reaches its 



position nearest the cylinder head. During this interval both the suction 

 and exhaust valves are closed. 



3. Working or third stroke, which begins when the explosive fuel is 

 fired and as soon as the piston again leaves its position nearest the cylinder 



Fig. 6. Scrubber. 



