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Popular Mechanics Co.

"The Boy Mechanic: Volume 1 700 Things for Boys to Do"

Fasten a weight to the other end of the line as
heavy as the motor or engine can lift and still run. It must weigh
enough to slow the power down a little, but not to stop it. Mark
the position of the weight and start the motor, at the same time
accurately measuring time in minutes and seconds it takes to lift
the weight from the lowest point to the highest. Next measure
accurately the distance in feet covered by the weight in its
ascent and obtain the correct weight in pounds of the weight.
Multiply the weight by the distance covered and divide the result
by the number of minutes or fraction of a minute obtained and
divide this last result by 33,000 and the quotient will be the
horsepower of the motor or engine.
Perhaps an illustration will make this solution much plainer.
Suppose the motor will lift a weight of 1 lb. and still revolve,
30 ft. in 10 seconds or 1/6 of a minute. Multiplying 1 by 30 we
get 30, which divided by 1/6 gives 180. This in turn divided by
33,000 equals in round numbers 1/200 part of a horsepower.
--Contributed by Harold H. Cutter.

** Illusion for Window Attraction [239]
Gold fish and canary birds, living together in what seems like one
receptacle, make an unusual show window attraction.


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