422 
FOREST AND STREAM. 
[March i 6, 1907. 
The Hydroplane. 
When a yachtsman, referring to a boat, tells 
you she is a hydroplane, your imagination im¬ 
mediately starts to build up all sorts of freaky 
craft; but when you see the actual boat itself 
all the high strung imagination falls flat. Visitors 
invited to witness the first trial in this country 
MR. CHAS. CANAUX, OF FRANCE. 
Inventor of the Hydroplane Boat. 
of a hydroplane saw nothing but a scow, and a 
very small one at that, floating on the cold waters 
of the Harlem River. 
She is 11ft. long and 3ft. 4m. wide and has 
just room enough in her small open cockpit to 
hold the inventor, a Frenchman, named Charles 
Canaux, and the small 8 horsepower DeDion 
MR. CANAUX SEATED IN THE STERN OF THE HYDRO 
PLANE BOAT READY TO RUN HER. 
gasolene engine that furnishes the motive power. 
Our photograph here shows Mr. Canaux seated 
in the stern of the boat with all the controlling 
devices to the engine right at his hands. The 
gasolene feed tank held up by an iron frame 
forms a chair back. On each quarter may be 
seen the two rudders by which the craft is con¬ 
trolled. When at top speed both rudders hang 
useless as there is no water on the inside of 
them, nothing but air, while along the outside 
sweeping aft a wall of water rushes by and it 
takes but a touch on the tiller of the rudder on 
whichever side the operator wishes to go to turn 
the boat, for the rudder touches a column of 
water going 20 miles or more an hour. The 
strings to the tillers prevent their surging against 
the transoms. She is a crude looking craft, yet 
deserving of far more attention than the first 
glance would suggest. The hull built by Rud- 
dick, of shell boat fame on the Harlem River, 
only weighs by actual weight 100 pounds and is 
built of two thicknesses of veneer with x / 2 in. 
timbers. The engine, the only one available for 
this hurried demonstration, was an 8 horsepower 
air cooled DeDion engine, that weighed 120 
pounds. With all necessary piping, fittings, etc., 
the hull and engine weighs 350 pounds, and with 
her crew the total displacement or weight was 
500 pounds. 
Her propeller is extremely narrow two-bladed, 
with 51 inches pitch, but as this did not give the 
best results a new one, three-bladed, of 8^201. 
diameter, is being finished for another trial trip. 
This two-bladed propeller drove her over the 
Speedway quarter mile at an average, with and 
against the wind at slack tide, of 21.02 miles an 
hour. 
Her appearance under way was a most 
startling revelation to all who'make a study of 
marine propulsion. None but a clear-headed man, 
with his mind entirely unfettered by past rules and 
accepted laws in relation to boats, would have 
had the nerve to build such an odd craft and 
put her to a test. 
At a first glance any one would condemn the 
shape of her bottom; the idea of a square sub¬ 
merged transom in the middle of her seemed 
ridiculous. But, when its use has once been 
demonstrated, as, thanks to the nerve of Mr. 
Canaux, has now been done, wise ones seek for 
a reason. That reason is not hard to find. We 
can all see daylight after this nervy inventor let 
the shade go up. Have not our own designers 
learned the same lesson in motor boats’ sterns 
that this boat’s shape demonstrates in an ex¬ 
treme degree? As greater speeds were attained 
did not the flat transom succeed the pointed one? 
And this flat transom, at first kept about six 
inches above the water level so it would not 
drag, has gradually dropped lower and lower 
until now it is as many inches under water as it 
formerly was above. Yet it clears itself with no 
more resistance than formerly; in fact with less. 
The hydroplane is that principle utilized to 
its full extent. The propeller pushes the light 
hull up the flat inclined plane of water that 
opposes its forward motion and, though there 
is great fuss at low speeds, yet when going as 
these boats are designed to go, the hull lifts it¬ 
self bodily up on the top of the water and skips 
along over it. Lifting up the more easily the 
THE HYDROPLANE BOAT AFTER HER TRIAL ^PINS ON 
THE HARLEM RIVER. 
harder it is driven, and lessening its resistance 
the more it lifts. 
All the intricate wave-making theories, like the 
water under the shovel-shaped bows of this craft, 
are broken up and ironed out as .smooth as the 
flat band of smooth water that hisses out clean 
PECULIAR WAVE FORMATION OF HYDROPLANE BOAT. 
Diagrams 1 and 2 show Hydroplane boat lying still and in motion, the wake of what might be termed the forward 
hull exerting an upward force against the after hull. The object sought is to lift the hull as much as possible out 
of water. 
