g in this box."

"Yes," replied Zero, with the same slow weariness of manner, "I have set
several of them going."

"My God!" cried Somerset, bounding to his feet. "Machines?"

"Machines!" returned the plotter bitterly. "Machines indeed! I blush to
be their author. Alas!" he said, burying his face in his hands, "that I
should live to say it!"

"Madman!" cried Somerset, shaking him by the arm. "What am I to
understand? Have you, indeed, set these diabolical contrivances in
motion? and do we stay here to be blown up?"

"'Hoist with his own petard?'" returned the plotter musingly. "One more
quotation: strange! But indeed my brain is struck with numbness. Yes,
dear boy, I have, as you say, put my contrivances in motion. The one on
which you are sitting, I have timed for half an hour. Yon other----"

"Half an hour!" echoed Somerset, dancing with trepidation. "Merciful
heavens, in half an hour?"

"Dear fellow, why so much excitement?" inquired Zero. "My dynamite is
not more dangerous than toffy; had I an only child, I would give it him
to play with. You see this brick?" he continued, lifting a cake of the
infernal compound from the laboratory-table. "At a touch it should
explode, and that with such unconquerable energy as should bestrew the
square with ruins. Well, now, behold! I dash it on the floor."

Somerset sprang forward, and, with the strength of the very ecstasy of
terror, wrested the brick from his possession. "Heavens!" he cried,
wiping his brow; and then with more care than ever mother handled her
first-born withal, gingerly transported the explosive to the far end of
the apartment; the plotter, his arms once more fallen to his side,
dispiritedly watching him.

"It was entirely harmless," he sighed. "They describe it as burning like
tobacco."

"In the name of fortune," cried Somerset, "what have I done to you, or
what have you done to yourself, that you should persist in this insane
behaviour? If not for your own sake, then for mine, let us depart from
this doomed house, where I profess I have not the heart to leave you;
and then, if you will take my advice, and if your determination be
sincere, you will instantly quit this city, where no further occupation
can detain you."

"Such, dear fellow, was my own design," replied the plotter. "I have, as
you observe, no further business here; and once I have packed a little
bag, I shall ask you to share a frugal meal, to go with me as far as to
the station, an