That idea he had carried into execution before the bed was delivered at the embassy; and it consisted in having a hollow receptacle bored into each of the legs of the bedstead.
Now stop a moment and consider just what this meant.
Remember that each of the legs of the bed held a caster; that the caster had to be affixed to a plug which would fit into the bottom of the hole, before it could do its duty. Remember that the foot-end of that bedstead was so heavy that three ordinary men could not have lifted it from the floor after it was in place, to remove the caster, and to get at the receptacles which they concealed.
Well, that was the condition.
The holes were bored into the legs of the bedstead, before the bedstead was delivered; the casters were arranged so they could be removed. After that, the ambassador simply kept an automobile jack in one of the closets of his room—and so you see, he was able to jack up the bed at any time he so desired, remove the caster, and to get at his tin cylinders.
And here the ambassador had been cute again.
Although there was a receptacle in each one of the legs of the bedstead, he made use of only one of them; but that one was bored to twice the length of the tin cylinder, and, instead of hiding the two cylinders he wished to conceal inside two of the hollows, he put them both in the same one; one above the other, affixing the top one in its place by sticking it there with a piece of wax, so that it would cling, but yet could be easily dislodged.
That fact had saved one of the cylinders when the other had been stolen.
Doubtless it had not occurred to the thief that both cylinders were in the same cavity, and probably they had searched all four of them; but it remained that one of them had not been taken.
The problem was, how had any person been able to discover the hiding place?