PROFICUOUS

What is the most proficuous simple machine of them all?
The contenders are six so certainly five of them will fall
A wheel and axle is a good candidate both large and small
And so does a lever remain ready for my beckon call
Or a wedge like a long shiny nail driven into a wall
Or an inclined plane as a handicap ramp entering a mall
Or the pulley where with one finger you can lift a 20 ton ball
Or the versatile screw holding the boards on a livestock stall?

My vote is for the inclined plane as the most proficuous of all
Without the inclined plane all of the others wouldn’t exist at all
A lever is a hinged inclined plane one side to rise the other to fall
A wedge is simply a moving inclined plane and that’s all
A wheel and axle is merely a lever with fulcrum as axle, that’s all
A pulley is a series of wheels and axles working in harmony, that’s all
And a screw is a wedge or inclined plane around a central core, that’s all

So the winner is as plain to me as the nose on your face
The inclined plane is the champion and certainly deserves first place.

(Adj. – useful or profitable)