Powerboat

“ Again we travel the weary road in the quest after more power for storage battery and dynamo. And then, when it is finally solved, some one asks, "What if the engine breaks down?" And we collapse. There are the sidelights, the binnacle light, and the anchor light. Our very lives depend upon them. So we have to fit the boat throughout with oil lamps as well.
But we are not done with that engine yet. The engine is powerful. We are two small men and a small woman. It will break our hearts and our backs to hoist anchor by hand. Let the engine do it. ”

“ All these boats should have a motor-engine in them. And, of course, the glorified tradesman, the mummified official, the technicians, and all these secretly disconcerted hangers-on to the enormous ticket-selling enterprise, will raise objections to it with every air of superiority. But don’t believe them. Doesn’t it strike you as absurd that in this age of mechanical propulsion, of generated power, the boats of such ultra-modern ships are fitted with oars and sails, implements more than three thousand years old? ”

“ When moving on the surface it has the appearance of an ordinary ship, with its two light masts, a small conning-tower on which is the steering-wheel, bowsprit, ventilators, a derrick, suction-pump, and two anchors. A gasolene engine of special design is used for both surface and submerged cruising under ordinary circumstances, but in time of war storage batteries are available. An electric dynamo supplies light to the whole interior, including a 4000 candle-power searchlight in the extreme bow which illuminates the pathway while under water. ”

“ Now we are rising to the surface. By the use of the rudder the boat pushes forward faster and faster to the surface of the water. In order to accelerate the ascent compressed air is forced into one of the submersion tanks.
Now she moves very rapidly: the tower is already free. The deck rises dripping out of the water, the conning-tower hatch is opened, fresh air streams in, and I give the command:
"Blow out ballast tanks!"
A wild howling and screeching comes in reply from the control-room, while the powerful turbine engine presses the water out from the submerging tanks. ”

“ The amount of time which a submersible may [Pg 297] run beneath the waves depends upon her speed. The best of the German undersea boats, it has been estimated, could not remain under more than three hours at high speed. They then had to come up, as the navy saying has it, for "more juice." To be more explicit, a submersible has a mechanical process, a combination motor and dynamo between the engine, which drives the boat when it is on the surface, and the thrust block through which the shaft runs to the propeller. ”

“ Up and down is doubtless wrong, for who could propel a boat upstream against a foaming current going over ten miles an hour, and often nearer fifteen! Discussing this with our guide, he declares he feels like going up in the motor-canoe as far as he can, and, he adds, “By George, I believe I can get through!” We laugh him to scorn. He persists in trying it. At last we decide to join in the experience.
We oil up and make all ready. Off we go! right into the midst of the foam at the lower end of the rapids. The engine works furiously at full speed while we watch results. ”

“ The boat’s engine is a powerful three-cylinder pump, and it sucks the water strongly in through the tubes which point forward, discharging it as powerfully out through those which point astern; thus drawing and driving the boat along at a speed of about twelve knots per hour, which is as fast, I fancy, as we shall ever want her to go. If you want to go astern the movement of a single lever reverses the whole process. ”

“ You must have had some practice aboard rather goodsized craft?"
"Never anything much bigger than a thirty-foot gasoline boat," Jack replied. "In the old days, sir, a young sailor had to begin with a rowboat, go on to a cat-boat, and so work on up until he could handle a full-rigged ship. That's where the change has come with to-day's gasoline boats. A fellow who learns to run a twenty-foot gasoline launch can just as easily handle a big gasoline yacht of any size. The new style of power saves a heap of time in the learning, sir." ”

“ When mechanical propulsion is the auxiliary power, we have a different problem. Take a vessel capable of being driven by sail at a speed of eight knots, and by her engines alone at four knots. Now, if she be sailing at a speed of eight knots, and we start her engine to make the number of revolutions necessary to induce a speed of four knots, the screw, not traveling as fast as the hull, will be dragged to the amount of the difference between its speed and the speed of the boat—four knots. ”

“ We must pass hastily over the other inventions, rapidly following each other, and all designed to make ocean travel more swift, more safe, and more comfortable, and to increase the profit of the shipowner. The compound engine, which has been so developed that in place of Fulton's seven miles an hour, our ocean steamships are driven now at a speed sometimes closely approaching twenty-five miles an hour, seems already destined to give way to the turbine form of engine which, applied thus far to torpedo-boats only, has made a record of forty-four miles an hour. ”

“ At the extreme end of the big bag were the various rudders and planes, designed to keep the craft on a level keel, automatically, and to enable it to make headway against a strong wind. The motive power consisted of three double-bladed wooden propellers, which could be operated together or independently. A powerful gasoline engine was the chief motive power, though there was an auxiliary storage battery, which would operate an electrical motor and send the ship along for more than twenty-four hours in case of accident to the gasoline engine. ”

“ The engine room of the White Shark was an odd looking place. Instead of pipes and valves, wires and switches were everywhere. In the center of the metal floor26 were two powerful electric motors, and at the side of each was a dynamo which, Mr. Dancer explained, connected with the storage batteries in which electricity was stored for practically every purpose on the diving craft.
“I light, cook, and drive my engines by electricity,” explained their guide; “in fact, everything on board is done by it. Even my steering devices and aluminum diving apparatus is electrically controlled. ”

“ Even then the power is short-lived. However, building a few small boats driven by rubber-band motors [50] will do much to teach the young boat-builder some valuable lessons in boat construction.
Probably the best method of propelling model boats is the electric method. By building a boat large enough to accommodate two dry batteries or a small storage battery and a little power motor, a very reliable method of propulsion is made possible. The boat must have sufficient displacement to accommodate the weight of the dry-cells and storage battery. ”

“ Most of to-day I spent tinkering with the engine. It goes now—in a water barrel. The trouble with the best of these little motors is that the moment they get wet they stop, and they are attached at such an exposed place, on the stern, that they will get wet if there’s much of a sea. Then you’re in a bad fix for it’s impossible to make any headway rowing with the engine—or rather the propeller—dragging. Most of the engines are hung right on the stern and can be readily detached and drawn into the boat. ”

“ Stephen has just completed his first Hydro-Aircraft, and while I am in San Diego I shall test it and make a long trip over the Pacific Ocean to exploit its powers. Such a machine would not take the place of a yacht, you know, and the motor boat attachment is merely a safety device to allow one to fly over water as well as over land. Then, if you are obliged to descend, your aircraft becomes a motor boat and the engines propel it to the shore. ”

“ The installation of power is effected by introducing a 25 H.P. four-cycle gasoline motor, weighing with its fittings, tanks, &c., about 800 ℔. The engine is installed in the after air chamber, with the starting crank, reversing clutches, &c., recessed into the bulkhead to protect them from accidents. These boats attain a speed of from 7 to 9 m. an hour, and have proved extremely efficient. A new power life-boat (fig. 10) on somewhat improved lines, 36 ft. in length, and equipped with a 35-40 H.P. gasoline engine, promises to prove still more efficient. ”

“ The chugging of many motors—the churning to foam of the blue waters of the lake—a haze of acrid smoke hanging over all, as some cylinder did not properly digest the gasoline vapor and oil fed to it, but sent it out half consumed—spray thrown up now and then—the distant sound of a band—eager eyes looking toward the stake buoys—tense breathing—all this went to make up the race in which our outdoor girls were taking part.
Foot by foot the Gem crept up on the Bug, which was the name of the foremost boat. Drop by drop Betty fed more gasoline to her striving motor. ”

“ The width of side-wheel boats will be reduced by from 20 to 30 per cent., and the draught of water will be diminished in screw steamers to that of the hull itself; the maneuver in which the power of the engine might be directly employed will be simplified; a machine will be had of a sensibly constant speed, and without change in its running; the production of waves capable of injuring the banks of canals will be avoided; the propeller will be capable of being utilized as a bilge pump; all vibration will be suppressed ”

“ He gave orders for carrying out anchors to moor the ship, for rigging tackle, for getting the diver's uniform ready for an under-water inspection of the hull; at the same time he directed the capable engineers, now that there was no more steam needed for the engine, to turn every ounce of power into the pumps, and, if possible, to rig others temporarily to clear the ship of water and keep it down, hoping that perhaps they could come at the leak from within as well as from without. ”

“ Should a car meet a hill too steep for its climbing powers, the engines must come to rest. The wheel does not slip on the road, and so long as there is sufficient power it will force the car up the severest incline; as soon as the power proves too small for the task in hand the car "lies down." In a motor boat, however, the engine may keep the screw moving without doing more against wind and tide than prevent the boat from "advancing backwards." ”

“ They are egg-or spindle-shaped, supplied with compressed air, able to sink and rise by rearrangement of water-ballast. Reservoirs in the hull are gradually filled for submersion with water, which is easily expelled when it is desired to rise again. If this system goes wrong a false keel of thirty-six hundredweight can be detached and the boat springs up to the surface. The propulsive force is electricity, which works the driving-screw at the rear, and the automobile torpedo is discharged from its tube by compressed air. ”

“ The main engine-room, containing the low-pressure turbines, is similarly protected against flooding.
Now, all of these bulkheads are carried up to a watertight connection with the upper deck, which, amidships, is over two decks, or say about 20 feet above the water-line, the exception being the first or collision bulkhead, which extends to the shelter deck. A most important feature of the protection, borrowed from warship practice, is that the lower deck, which, amidships, is located at about the water-line, is built of extra heavy plating, and is furnished with strong watertight hatches. ”

“ There were numerous gages to tell the depth to which the ship had sunk, the steam pressure, density of the water, and other necessary details.
There were dynamos to make light, motors to run the pumps, and a great storage battery, so that in case of a breakdown to the turbine engine the craft could be run entirely by electricity for a time. ”

“ Turning to the means of propulsion, we find sails as the main, or almost only, reliance during the early years of the century. The steam-engine operating paddle-wheels had come to be recognized as a possibility, and under certain conditions as a commercial success. The screw-propeller as a means of propulsion was known only as a freak idea, and was without status or recognition as a commercial or practical means for propelling ships. ”

“ It is probable that the introduction of the motor, instead of assisting to complete the departure of sails, will help in their being retained: for it has now been found commercially profitable to instal the internal-combustion engine in ships of a size not exceeding about seven hundred tons. By this means sail can be used in a fair wind, and the motor can take her along in calms, as well as in tolerable weather against a head wind. ”

“ You know, of course, that the ocean greyhound of to-day is a twin-screw ship—that is, that instead of being driven through the water by one propeller, she has two—one on each side of the end of her keel. Each screw is worked by its own set of engines. These engines are entirely independent of each other. The rudder is moved to one side or the other by steam or hydraulic power. Should the rudder become useless from any cause, it is possible to steer the ship by these screws. Most of you know that you can steer a row-boat by putting more force on one oar than on the other. ”

“ Similar considerations apply to the questions whether a submarine boat should have a separate means of propulsion for surface-running distinct from that fitted for submerged propulsion, and if so, whether it should consist of steam or internal-combustion engines. On account of the very limited capacity of even the best modern electric accumulator, any submarine which is intended to have a considerable radius of action must necessarily have heat engines of some description for surface propulsion and for charging batteries. ”