explosives."

"But THESE aren't textbooks," said Lady Agatha, who had pulled out
three long, narrow volumes from the pile. "They're in manuscript, and
they look more like account books."

The first of them, in Loge's handwriting, contained a series of notes,
mostly unintelligible to Cleggett, dealing with experiments in two
sorts of manufacture: first, the preparation of counterfeit money;
second, the production of dynamite bombs.

The second of the manuscript books was in cipher. Cleggett might have
deciphered it without assistance, for he was skilled in these matters,
but the labor was not necessary. The book was for Loge's own eye. A
loose sheet of paper folded between the leaves gave the key.

The book showed that Loge had been employed as an expert operator, in
the pay of a certain radical organization, to pull off dynamiting jobs
in various parts of the country. This was his account book with the
organization. He had done his work and taken his pay as methodically
as a plumber might. And he had been paid well. Cleggett guessed that
Loge was not particularly interested in the work in its relationship to
the revolutionary cause; it was the money to be made in this way, and
not any particular sympathy with his employers, which attracted Loge,
so Cleggett divined. Cleggett was astonished at the number of jobs
which Loge had engineered. The book threw light on mysterious
explosions which had occurred throughout a period of five years.

But it was the third manuscript book which displayed the real Logan
Black.

This was also in cipher. Dr. Farnsworth and Cleggett had translated
but a few lines of it when they perceived that it was a diary. With a
vanity almost inconceivable to those who have not reflected upon the
criminal nature, Loge had written here the tale of his own life, for
his own reading. He had written it in loving detail. It was, in fact,
the book in which he looked when he wished to admire himself.

"It is odd," said Cleggett, "that so clever a man should write down his
own story in this way."

"This book," said Farnsworth, "would be a boon to a psychologist
interested in criminology. You say it is odd. But with a certain type
of criminal, it is almost usual. The human soul is full of strange
impulses. One of the strangest is towards just this sort of record.
Cunning, and the vanity which destroys cunning, often exist side by
side. The criminal of a certain type almost worships h