orking a bicycle by a lever--
well, after that principle. There would be a steel rod with cog-
wheels, and one man could work the lever as the lame cyclist does
without the labour of rowing." Venning waited nervously for the
criticism.

"At any rate the lever would be a relief after the paddles," said
Mr. Hume, gravely.

"But that is not all," continued the inventor, hastily. "I would rig
up a light American windmill amidships, which could work the screw
and get more speed with a following wind in conjunction with a sail
rigged up forward."

"Bravo, my boy!" said Mr. Hume, laughing. "How many revolutions of
the screw to the minute do you expect to get out of your windmill?"

"That depends on the power of the wind, sir. Do you think it is a
mad scheme?"

"It would impress the natives," said Compton, "and at any rate we
could start wheat-milling, you know, in case we came to the end of
our resources."

"There's no wheat in Central Africa, you duffer! Besides, sir, it's
mainly a question of gear. With a lever, cog-wheels, and a running
chain after the pattern of the cycle chain, one could----"

"And ball bearings," suggested Compton, slyly.

"Yes; and ball bearings--the friction would be reduced, and we could
get more power out of a screw and propeller than we could from four
paddles."

"You may be right," said Mr. Hume, thoughtfully.

"We don't want to take a large party, and I confess the water
transport has bothered me very much. The wind-mill, I am afraid, we
must leave to some other time, but the other part of your scheme is
worth placing before practical men, and I will give you a letter to
a friend of mine who had a boat built on the Thames."

Venning saw the friend the very next day; the friend gave him an
introduction to a member of a great firm of torpedo-boat builders on
the Thames, and this gentleman very kindly gave the matter five
minutes' attention.

"Your idea, eh?" said the great designer. "Explain what advantage
you expect to gain."

"Less labour in working than with paddles, and greater speed."

"Humph! Well, my lad, you leave the matter with me, and I will
report. You can look over the yards if you like."

Venning spent the rest of the morning among the wicked-looking
sharks of the Navy, and he went back depressed with the thought that
his "sneak-box" was merely a plaything. However, he picked up
confidence when the next day brought an offer from the builders to
turn out an alumin