ou see, the pump would be arranged with cog-wheels
and all that sort of thing, and the power would be supplied by a
weight, which would be a cylinder of lead or iron, fastened to a rope
and run down inside your pipe. Just think of it! It would run down a
thousand feet, and where is there anything worked by weight that has
such a fall as that?"

I laughed. "That is all very well," said I. "But how about the power
required to wind that weight up again when it got to the bottom? I
should have to have an engine to do that."

"Oh, no," said he. "I have planned the thing better than that. You
see, the greater the weight the greater the power and the velocity.
Now, if you take a solid cylinder of lead about four inches in
diameter, so that it would slip easily down your pipe,--you might
grease it, for that matter,--and twenty feet in length, it would be an
enormous weight, and in slowly descending for about an hour a day--for
that would be long enough for your pumping--and going down a thousand
feet, it would run your engine for a year. Now, then, at the end of
the year you could not expect to haul that weight up again. You would
have a trigger arrangement which would detach it from the rope when it
got to the bottom. Then you would wind up your rope,--a man could do
that in a short time,--and you would attach another cylinder of lead,
and that would run your engine for another year, minus a few days,
because it would only go down nine hundred and eighty feet. The next
year you would put on another cylinder, and so on. I have not worked
out the figures exactly, but I think that in this way your engine would
run for thirty years before the pipe became entirely filled with
cylinders. That would be probably as long as you would care to have
water forced into the house."

"Yes"' said I, "I think that is likely."

He saw that his scheme did not strike me favorably. Suddenly a light
flashed across his face.

"I tell you what you can do with your pipe," he said, "just as it is.
You can set up a clock over it which would run for forty years without
winding."

I smiled, and he turned sadly away to his horse; but he had not ridden
ten yards before he came back and called to me over the wall.

"If the earth at the bottom of your pipe should ever yield to pressure
and give way, and if water or gas, or--anything, should be squirted out
of it, I beg you will let me know as soon as possible."

I promised to do so.