213.--TURKS AND RUSSIANS.

The main point is to discover the smallest possible number of Russians

that there could have been. As the enemy opened fire from all

directions, it is clearly necessary to find what is the smallest number

of heads that could form sixteen lines with three heads in every line.

Note that I say sixteen, and not thirty-two, because every line taken by

a bullet may be also taken by another bullet fired in exactly the

opposite direction. Now, as few as eleven points, or heads, may be

arranged to form the required sixteen lines of three, but the discovery

of this arrangement is a hard nut. The diagram at the foot of this page

will show exactly how the thing is to be done.

[Illustration]

If, therefore, eleven Russians were in the positions shown by the stars,

and the thirty-two Turks in the positions indicated by the black dots,

it will be seen, by the lines shown, that each Turk may fire exactly

over the heads of three Russians. But as each bullet kills a man, it is

essential that every Turk shall shoot one of his comrades and be shot by

him in turn; otherwise we should have to provide extra Russians to be

shot, which would be destructive of the correct solution of our problem.

As the firing was simultaneous, this point presents no difficulties. The

answer we thus see is that there were at least eleven Russians amongst

whom there was no casualty, and that all the thirty-two Turks were shot

by one another. It was not stated whether the Russians fired any shots,

but it will be evident that even if they did their firing could not have

been effective: for if one of their bullets killed a Turk, then we have

immediately to provide another man for one of the Turkish bullets to

kill; and as the Turks were known to be thirty-two in number, this would

necessitate our introducing another Russian soldier and, of course,

destroying the solution. I repeat that the difficulty of the puzzle

consists in finding how to arrange eleven points so that they shall form

sixteen lines of three. I am told that the possibility of doing this was

first discovered by the Rev. Mr. Wilkinson some twenty years ago.

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