560 



Popular Science Monthly 



WAIL SEPARATING INTAKE 

 AND EXHAUST MANIFOLDS) 



The little trolley boat has sol\/:ed the problem 

 of preventing canal ice from accumulating 



Trolley Cars on the Water? Yes; 

 and in New York State 



IT seems reasonable to conclude that if the 

 electric trolley boat illustrated were in- 

 troduced into Am- 

 sterdam or Venice, it 

 would soon develop 

 into a practical and 

 popular "jitney boat." 



The craft shown is 

 by no means an ex- 

 periment, but was de- 

 signed to break up 

 ice jams and prevent 

 them from clogging the intake canal oi one 

 of the great power companies of Niagara 

 Falls. The ice problem has always worried 

 the water power enterprises at Niagara. 

 Large cakes enter the canal from the Great 

 Lakes. To prevent these from accumulating 

 near the power houses, where they would 

 immediately check the flow of water neces- 

 sary for operation, the boat is used. 



The hull of the boat greatly resembles 

 that of a submarine as it is made entirely of 

 steel. Although the craft is only eighteen 

 feet long, it carries a seventy-five horse- 

 power motor which gives it unusual power 

 to buck the huge ice cakes out of the way. 



Increasing the Power of Automobile 

 Engines with Mufflers 



GREATER power is secured from an 

 automobile engine if the exhaust gases 

 are completely rather than partially re- 

 moved from the cylinders just before each 

 power stroke. While this can be accom- 

 plished if the motor has but one cylinder it 

 is more difficult when two or more cylinders 

 are employed, for the reason that two or 

 more cylinders are connected through the 

 exhaust manifold. This is due to the over- 

 lapping periods during which the exhaust 

 valves are kept open. 



Under such conditions, the resistance or 

 back pressure caused by the gases forced to 

 pass through a muffler tends to make the 

 pressure of the beginning exhaust hold back 

 the gases in the cylinder from which the 

 exhaust is nearly completed. This decreases 

 the volume of new fuel gas and lessens the 

 power from its explosion. 



These conditions have been largely over- 

 come by the invention of an Indiana 

 engineer, in which a number of mufflers are 

 employed. In the case of the six-cylinder 

 motor shown in the accompanying sketches 

 two mufflers are used. Each is connected 

 with three cylinders so that successively 

 exhausting cylinders operate through dif- 

 ferent manifolds instead of the same one. 

 By this means, only one exhaust valve is 

 open at a time. 



INTAKE MANIfOLD' 



Each of the mufflers is connected with three 

 cylinders so that successively exhausting 

 cylinders discharge through separate manifolds 



