THE CANTERBURY PUZZLES
brim. The price was to be a certain amount per cistern, including
cost of labour. Now Mr. Solders is a thrifty man, so he naturally
desired to make the two cisterns of such dimensions that the smallest
possible quantity of metal should be required. This was the little
question that was so worrying him.
Can my ingenious readers find the dimensions of the most
economical cistern with a top, and also the exact proportions of such
a cistern without a top, each to hold 1,000 cubic feet of water? By
" economical " is meant the method that requires the smallest possible
quantity of metal. No margin need be allowed for what ladies
would call " turnings." I shall show how I helped Mr. Solders
out of his dilemma. He says : " That little wrinkle you gave
me would be useful to others in my trade."
98.—
The Nelson Column.
During a Nelson celebration I was
standing in Trafalgar Square with a
friend of puzzling proclivities. He
had for some time been gazing at
the column in an abstracted way,
and seemed quite unconscious of the
casual remarks that I addressed to
him.
" What are you dreaming about ? "
I said at last.
" Two feet " he murmured.
" Somebody's Trilbys ?" I in-
quired.
" Five times round "
" Two feet, five times round !
What on earth are you saying ? "
" Wait a minute," he said, begin-
ning to figure something out on the
back of an envelope. I now detected that he was in the throes
of producing a new problem of some sort, for I well knew his
methods of working at these things.
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