of success, the same means, ten days had been enough for Lupin.

What were those elements, those means, those chances? They were
reduced, when all was said, to a knowledge of the pamphlet published in
1815, a pamphlet which Lupin, no doubt, like Massiban, had found by
accident and thanks to which he had succeeded in discovering the
indispensable document in Marie Antoinette's book of hours.

Therefore, the pamphlet and the document were the only two fundamental
facts upon which Lupin had relied. With these he had built up the whole
edifice. He had had no extraneous aid. The study of the pamphlet and
the study of the document--full stop--that was all.

Well, could not Beautrelet confine himself to the same ground? What was
the use of an impossible struggle? What was the use of those vain
investigations, in which, even supposing that he avoided the pitfalls
that were multiplied under his feet, he was sure, in the end, to
achieve the poorest of results?

His decision was clear and immediate; and, in adopting it, he had the
happy instinct that he was on the right path. He began by leaving his
Janson-de-Sailly schoolfellow, without indulging in useless
recriminations, and, taking his portmanteau with him, went and
installed himself, after much hunting about, in a small hotel situated
in the very heart of Paris. This hotel he did not leave for days. At
most, he took his meals at the table d'hote. The rest of the time,
locked in his room, with the window-curtains close-drawn, he spent in
thinking.

"Ten days," Arsene Lupin had said.

Beautrelet, striving to forget all that he had done and to remember
only the elements of the pamphlet and the document, aspired eagerly to
keep within the limit of those ten days. However the tenth day passed
and the eleventh and the twelfth; but, on the thirteenth day, a gleam
lit up his brain and, very soon, with the bewildering rapidity of those
ideas which develop in us like miraculous plants, the truth emerged,
blossomed, gathered strength. On the evening of the thirteenth day, he
certainly did not know the answer to the problem, but he knew, to a
certainty, one of the methods which Lupin had, beyond a doubt, employed.

It was a very simple method, hinging on this one question: Is there a
link of any sort uniting all the more or less important historic events
with which the pamphlet connects the mystery of the Hollow Needle?

The great diversity of these events made the question diff