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over the rafts or floats. This system of shafting, deriving its power from a gasoline engine sheltered in the houseboat, transmits through bevel gears, the power necessary to drive the circulation propellers in each of the hatching bags. To conform to the undulating movement of the floats, the shaft from the engine house is connected to the floats by a flexible joint and the shafting used on the floats is of such small diameter that the motion of the water bends it without tearing off shaft hangers or breaking the shafting. Two floats are used, one on eacli side of the houseboat, and from these are suspended twenty-eight rearing bags ten feet square and four feet deep.

The engine gives a speed of 360 revolutions and this is reduced by belting to forty and finally, through gearing, to twenty and ten, the last named being the revolutions per minute that the "fans" run during the culture of the lobsters. The paddles are painted white, as the young lobsters tend to avoid all white surfaces, and the white sides and bottoms of the hatching receptacles pro

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tect the delicate larvae from injury by being thrown against the container or ventilating paddles. In the making of the ventilating paddles only by years of study was it possible to arrive at the proper angle for the blades of the paddles to impose against the water, it being found that an infinitesimal variation in this respect was the cause of total failures, resulting in the death of a large number of fry and poor larvae. The current given by the paddles must be just strong enough to keep the food in motion, prevent cannibalism by constant circulation, and keep the larvae from collecting at the bottom of the bag and rolling over with the food silt and diatoms that have collected there. The strength of current also affects molting, which is the process of growth in the Crustacea, the growth being accomplished between the time of casting off the old shell and the hardening of the new coat.

The lobster fry eat ravenously in all stages and the feeding assumes great importance as the young lobsters molt three times in from ten to fourteen days. Under such conditions the feeding is

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constant and regular. Scrambled hen's eggs, liver, and beef are used for food in a finely cut form to allow the gentle current of water to carry it within easy reach of the larvae, and the feeding is attended to every two hours throughout the full twenty-four of each day and night. To rear a lobster to the fourth stage for planting at the Wickford hatchery requires from ten to twenty-one days, depending mostly on the temperature of the water, and the young "lobsterlings" are planted after reaching this stage of maturity known as the first "ground" stage because of the fact that during the fourth stage the lobster takes up its abode among the rocks and grass at the bottom for the first time. As fast as the lobsters reach this latter stage of development they are dipped out, a few at a time, and counted. They are then put in a planting can and are due to be "planted" in the briny deep. To allow the fourth stage fry to take full advantage of their hiding instinct for protection after planting, they are poured out at the water's edge where an abundance of eel grass and rocks tend to make a natural harboring place for the young lobsters till they attain their full growth.

With this method developed to the fine point it has been at the Wickford Station, it has been accurately calculated, not "estimated," that from forty per cent, to seventy per cent, of the eggs yielded by the egg lobster reach the fourth stage of development. As their most precarious period of existence is during the first three stages, the fourth stage lobsters have an infinitely greater chance to survive against the natural enemies around them than would be possible under any circumstances with the first stage larvae as still liberated by the other state and government establishments.

After hatching is over the female lobsters arc again consigned to the waters from which they came and are put backin pre-determined localities with copper tags fastened to them giving a recorded number. The fishermen are requested to return the tag to the station with information as to the locality of the trap it was caught in. By this method the egg bearing lobsters have furnished valuable data regarding their movements, after their period of usefulness at the station has expired.

The unique plant which this new process of culture has successfully dem

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THE CHAMPION COAL EATER. An engine of this type consumed 4.25 tons of coal per hour in a test run with seven coaches, making sixty-five miles per hour.

MACHINES TO FIRE LOCOMOTIVES

By

CHARLES FREDERICK CARTER

IF official prophecies are entitled to credence the next great evolution in railroad operation will be the general introduction of automatic stokers to relieve locomotive firemen of a task that has grown beyond the powers of human muscles. For three consecutive years the standing committee on stokers of the American Railway Master Mechanics Association has predicted the early advent of the automatic, or mechanical, stoker: and according to popular belief, "three times is the charm."

In 1908 the committee said in its report to the annual convention, "Mechanical stokers used on locomotives in this country up to the present time have at least demonstrated the fact that freight and passenger engines in road service can be successfully fired by mechanical means. Mechanical stoking, however, has not made much progress abroad.".

In its 1909 report the committee grew more bold, saying, "Results hold out great hopes for the future, particularly as the question has been taken up seriously by a number of railroads. . .

"It is reasonable to assume that the average tractive power of locomotives will increase. It is within the possibilities, therefore, that the increased fuel con

sumed per mile will render it advisable to provide mechanical means for firing locomotives in order that they may develop high sustained tractive effort and render the service attractive to men who possess the qualifications to become successful locomotive engineers. A successful automatic stoker should render locomotive firing more attractive, raise the standard of the service, permit close attention to the economic handling of fuel and the reduction of black smoke, enable firemen to become better acquainted with the general duties of a locomotive engineer and reduce tube and firebox troubles."

By the time the 1910 convention had assembled the stoker committee had become fully converted, as may be gathered from its report which contained this declaration: "The committee is convinced that the mechanical stoker is destined to be a very important factor in the operation of heavy locomotives in the not very distant future."

Railroad men have no occasion to read the unemotional reports of the committee to be convinced of the urgent need of a satisfactory automatic stoker; but since it is not the privilege of everybody to be railroad men it may be well to give some

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