cestral history, "six-footers" running in both sides of the family. Environmental conditions were much the same.

It is obvious from a comparison of the individuals in the ancestry of the two boys that the short student is short principally because his ancestors were short, while the tall one gains his height likewise from heredity. Bad environment might have stunted the latter; good environment never could have made the short student tall.

Herein is seen the effect of environment alone. The crowding, which curtailed the supply of moisture, or food constituents, from the soil, and the supply of light and air, affected not only the height of the plants, but also their reproductive organs. Had the grower avoided the bad environment, or crowded condition, he undoubtedly would have had corn in this plot just as good as that where the conditions were favorable.

was the same. On one side, the seed was planted far apart in hills; on the other side, it was planted close together, all other conditions being exactly the same. That corn which had abundance of space produced many and full ears; that which was crowded brought forth no ears, except for the few plants on the edge, which bore a few nubbins with scanty kernels.

On the other hand, if, instead of the naturally tall Leaming dent, the growers had planted some such variety as Tom Thumb pop corn, the plants in the area with abundance of space would still have been dwarfs, and their

ears would have borne only tiny kernels. Heredity would prevent this corn from being any

thing other than small, no matter how favorable the environment.

From this it would seem that heredity is the fundamental cause of height difference in any one generation, and that environment in any generation can only prevent full hereditary growth. The bigger problem-that of determining the effect of these factors throughout many generations is untouched by this study.

paid to speed. The little hydroplane is no pleasure boat. It is a racing machine and if it stays on top until the race is done the driver is happy. But if it should not-well, there is always the life pre

server.

The day is not long past when someone, fighting the resistance of water which has kept nautical travel in a class with the donkey for speed, thought of lifting the boat out of the water as it moved, by the shape of the very hull itself. The fast motorboat was then a "displacement" boat, very long, very narrow, deep, designed to cut the water like a knife and at the same time to spread the weight over a large area. Then, like a camel's foot on the sand, it would be buoyed up, and yet would cut and give great speed. Steps or planes pulled the displacement boat out of the water and made it into a hydroplane, and with this development has come speed which even the most ardent believers hardly dreamed of. With the planes came racing which has hardly an equal for thrill -and after a few trials, came the life preserver, worn by the crew.

With a little sea, when the waves begin to curl, the machine may become unmanageable. The boats are short because they must be light; they have tremendous power because they must over

come the pull of the water. To speed up almost any kind of power boat, the formula of three times the power to make twice the speed has been necessary, and that is the reason that America's largest, and, probably, fastest boat carries a rated horsepower of sixteen hundred. With this great power, developing great speed, the effect of a slight upset in balance can be easily understood. Imagine a speeding railway engine running on a base that jumped and swayed as does any boat when there are waves. With this combination, take the base completely out from under the fast-moving vehiclefor that is, in effect, what happens when a wave lifts the hydroplane's stern only. Down goes the nose! The life preserver floats a driver and a mechanic.

But this danger of diving has taught something of a lesson to the designers. of the fast motorboats of today. Hardly a year or two ago, every race report carried the story of a dive, neatly hidden in a paragraph far down the column so that people would not overestimate its importance and become prejudiced against the sport. It does not happen quite so often now, but there are other factors, factors that make it necessary for the

THE MOST POWERFUL CRAFT IN THE GAME The boat in the lead is Disturber IV, which was built by a Chicago man to compete in the Isle of Wight races, and was given eighteen hundred horsepower to insure success.

drivers to learn their little mounts, just as an aviator must learn to handle a flying machine in dangerous cross currents. There are corners to take, for the races are held to start and finish from the same place, ordinarily. There is jockeying to be done, as the riders of the race horses

must jockey with their mounts to bring home a winner. The race is not necessarily to the fleet, but to the fleet with a scheming, careful driver at the wheel.

Time after time Baby Reliance V has run away from Baby Speed Demon II, for these two boats are the hottest rivals of America's race courses, and they meet at every regatta. But did Baby Reliance take the cups at the winter races on Biscayne Bay, near Miami, Florida, last January? No. Bob Edgren drove the Demon to victory with two seconds to spare and how he did it is a secret that he and his mechanic have not revealed. The two boats were built by the same company on the same general principles and they are nearly equal in speed; but occasionally, Commodore Blackton, driving Baby Reliance, is beaten, and often it is because of some well planned scheme that wins for her rival, or as often, perhaps, because some scheme of her own driver fails. There is an art in taking stakes, or going around the corners of the course. There are points in driving

Not long ago, there came out of the West a boat that swept the eastern designers off their feet. It was a hydroplane, and one of the happiest thoughts of a man who worked in models of motorboats. The little speeder was shipped two or three thousand miles East and when she was ready to be taken back, her owners had collected a mass of cups

often the layman can hardly tell a step boat from a very fast displacement, or V-bottom boat; and with the change has come a little more safety to the men who inhale the smoke and gas that issues from the vent pipes of the roaring engines.

There is still the task at the turn, the danger which the driver faces when he must reverse his direction by rounding a

and silverware that represented a triumph entirely new in the hydroplane game. The boat was the Oregon Kid, and she swept the boards in company which sneered when she first appeared. She was two feet wider than her rivals. Today her rivals are faster because they, too, are that much wider than their predecessors. It was a radical departure and one that helped the sport amazingly, for it almost stopped the diving tendency of the boat. Once, because the hydroplane leapt over the sea, it was nicknamed the jackrabbit of the waves. Since designers have learned that jump

buoy, or make a turn at right angles to keep to the course. Like the automobile, the hydroplane skids. With nose in the air, the stern slides, the boat wheels like a soldier doing a right-about-face. In a close race, the boat which makes the shortest turns-covers the least water on the circle-has the advantage. This has brought out the bow rudder that has been used on some boats, but the skill and the element of danger are there to stay. The boat approaches in a smother of foam and the view of the spectator is obliterated. Many a race has been won and lost at the buoys. Not long ago