without ado round the house to the front gate on the road. He had put
his left hand under his coat to press it against his aching shoulder,
and his right hung palpably helpless. This rendered it impossible for
him to shake hands with his guest in parting.

"You're sure there's nothing I can do," said Theron, lingering on the
outer side of the gate. "I used to rub my father's shoulders and back;
I'd gladly--"

"Oh, not for worlds!" groaned the doctor. His anguish was so impressive
that Theron, as he walked down the road, quite missed the fact that
there had been no invitation to come again.

Dr. Ledsmar stood for a minute or two, his gaze meditatively following
the retreating figure. Then he went in, opening the front door with
his right hand, and carrying himself once more as if there were no such
thing as rheumatism in the world. He wandered on through the hall into
the laboratory, and stopped in front of the row of little tanks full of
water.

Some deliberation was involved in whatever his purpose might be, for he
looked from one tank to another with a pondering, dilatory gaze. At last
he plunged his hand into the opaque fluid and drew forth a long, slim,
yellowish-green lizard, with a coiling, sinuous tail and a pointed, evil
head. The reptile squirmed and doubled itself backward around his wrist,
darting out and in with dizzy swiftness its tiny forked tongue.

The doctor held the thing up to the light, and, scrutinizing it through
his spectacles, nodded his head in sedate approval. A grim smile curled
in his beard.