aid, "I am in a great hurry. May I be conducted in a
police car? Might as well. I'll be working with you hand and glove
until Barter is captured."

Bentley rode behind a shrieking siren to the home of the Estabrooks
... while from a distance of two miles Caleb Barter watched every
move and chuckled grimly to himself.

CHAPTER III

_Hell's Laboratory_

The huge room was absolutely free of all sounds from anywhere save
within itself. The walls, the floors, the doors were of chrome steel.
The cages were iron-ribbed and ponderous.

The long table which ran down the strange room's center was covered
with retorts, test tubes, Bunsen burners--all of the stock-in-trade of
the scientist who spends most of his time at research work. The man
who bent over the table was well past middle age. His hair was
snow-white, but his cheeks were like rosy red apples. He literally
seemed to glow with health. He was like a strange flame. His hands
were slender, the fingers long and extraordinarily supple. His lips
were redder even than his cheeks, and made one, strangely enough,
think of vampires. His eyes were coal-black, fathomless, piercing.

On the bronze wall directly across the table from the swiftly laboring
man was a porcelain tablet set into the bronze, and in the midst of
the table were a score of little push-buttons. Above each was a red
light; and below, a green one.

Several inches below each green light was a little slot which
resembled a tiny keyhole, something like the keyhole in the average
handbag. There was a key in each hole, and from each key hung a length
of gleaming chain which shone like gold and might have been gold, or
at least, some gold-plated metal. On the dangling end of each chain
was another key which might have been the twin of the key in the hole
above.

In the space between the keyholes and the green lights there were the
letters and figures: A-1, B-2, C-3, D-4 ... and so on up to T-20.

Plainly it was the beginning of a complicated classification system
with any number of combinations possible.

- - -

Behind the working man the row of cages partially hid the brooding
horror of the place. There were twenty cages--and in each one was a
sulking, red-eyed anthropoid ape. Plainly the fact that the number of
apes coincided with the number of push-buttons, and with the number of
keys, to say nothing of the red lights and the green lights, was no
accident. The apes were sullenly