To the Editor of the Scientific American: I write to express my high appreciation of the great interest which since April 1st you have been manifesting in the upbuilding of the American merchant marine. Everything published on this subject, either in your editorial or your correspondence columns, is greedily devoured by this writer, who for the past twelve years has made a special study of ship subsidy, mail subsidy, postal subvention, preferential duties, free ships, and every other measure suggested by human ingenuity for restoring that branch of our merchant marine engaged in the foreign or deep-sea trade to the proud position it formerly occupied. The greatest difficulty in doing this seems to be in getting people living in the interior of the continent, remote from the seaboard, to take an interest in or to inform themselves on such matters. The writer bids you Godspeed in the work you propose to undertake. James G. McBride. Canton, Miss. One Man Who Saw the Meteor Train To the Editor of the Scientific American: Regarding the letter on your page 275 re “Meteor Train,” I was one of a party of about a dozen at Mamaroneck, New York, who saw the appearance substantially as described by Mr. Pfarre. Philadelphia, Pa. Edward T. Child. Lessons of the Gordon Bennett Flying Race. To the Editor of the Scientific American: With reference to the above subject in your issue of August 19th, will you kindly permit a few supplementary remarks in concurrence with Mr. Grover Loening's views thereon? Your contributor lays particular stress upon the difficulty experienced by such able exponents as Weymann and Leblanc in turning sharply at each pylon, and emphasizes on the other hand the facility and also marvelous “banking” performed by Ogilvie on the “Baby Wright." Now it is certainly correct that this feat is difficult at all times with such superficial area out of all proportion in the case of the 60 square feet surface of the clipped Bleriot, but it is also equally1 certain that the centrifugal force generated by the single tractor-screw is a factor not to be overlooked. That of the Nieuport was 7 feet diameter, the Bleriot 8% feet, while the twin propellers of the Wright are 8% feet each, the last however revolving in opposite directions and thus counteracting centrifugal action magnified in the monoplanes. Consequently, the Wright—or its equivalent, a monoplane with twin propellers—is able to “bank” acutely in negotiating turns which would necessitate wide curves with the single-screw type or an alternative loss of stability and disaster. A still further point of importance with monoplanes driven by twin screws is the greater velocity attainable over the biplane similarly propelled, with furthermore the facility to forge against stronger winds—a real desideratum. It is really extraordinary to note at the present moment the continuous copying universally of the Wrights' patent warping system, either flagrantly emulating the bending of the rear marginal tips in conjunction with the foot-operated vertical rudder, or the virtual reproduction of the same by means of ailerons —a system which although copied from nature is hy no means the most powerful in controlling lateral stability by the bird. That perfect aviator among other methods demonstrates to us that by warping, or rather depressing, the outer half of one wing and correspondingly elevating the othe', he obviates all danger of law litigation by encroaching on the Wright patent! Well might Mr. Grover LoeLiing in his able article refer to the emphasizing for t'le need of the “variable surface” monoplane shown by the Gordon Bennett race. Not only will greater speed be accomplished by the adoption of the bird-like win:;, but so will inherent or natural stability be automatically secured in tumultuous winds by means of flexible construction in addition to this urgent need for variable surface. Therefore, the lessons demonstrated not only by the Gordon Bennett flying race, but by daily flights throughout the globe, for the production and evolution of the ideal mechanical flying machine, may be succinctly summarized in the following requirements: (1) The improvement of the car or fuselage in finer stream-line Nieuport form; (2) twin propellers of large diameter to thus engage a larger volume of air or “disk area,” and rotating in opposite directions to minimize undue centrifugal force; (3) constructing the main planes flexible with small camber, high aspect ratio, and single-surfaced; (4) by superior lateral control other than that employed in the biplane of the Wrights and assured by the graduating of main spars toward the tips; (5) by variable surfacing of main planes or wings to insure higher speeds and susceptibility to encounter safely higher wind velocities by such diminution and augmentation of the supporting area; (6) the discarding of the vertical rudder acting in conjunction with the main planes for steering in the horizontal plane; (7) the need for compactly folding the wings against the side of a car when not in use or descent on water; (8) and the means for increasing or decreasing the angle of incidence of the main planes to suit the requirements of flight conditions. All the above essential features are by no means impossible to reproduce in one design, and will decidedly enable a monoplane to ascend and descend from water, and in due course to fly across the Atlantic. London, England. Edgar E. Wilson. The Proposed Safety Stop Locomotive Throttle To the Editor of the Scientific American: In the correspondence department of your issue dated August 19th, on page 167, I noticed an article by Aubrey D. Beidelman, of Braintree, Mass., headed: “The Bridgeport Railroad Wreck." In the last paragraph of his communication he offers the suggestion that the throttle and brake valve handle be provided with means to automatically bring them to positions that would shut off the steam and apply the brakes in the event of the engineer's becoming incapacitated from any cause. To quote from his article, “it would be necessary for the engineer to exert some little pressure on them” to prevent their action in this manner. He questions if a device of this kind would be inconvenient. To my mind it would be insufferably so. In traversing a rolling country it is necessary for the engineman to frequently change the position of the reverse lever, requiring the, use of at least one and usually both hands. It is at times necessary for him to use the injector on his side of the engine, due to the inability of the injector on the fireman's side to deliver sufficient water to the boiler. It is not an unheard of thing for an engineman to find it necessary to fill the lubricator while on the road. All these things take time; and while he was attending to them, the steam would be shut off and the brakes applied, causing a considerable and undesirable reduction in speed. • In addition to his physical duties, he has to keep in mind the orders he has received, which govern his movements with respect to other trains that may be on the road, their meeting and passing points, and what time he has in which to make a given point before another train. This would be extremely difficult for a man under the continuous physical strain that would be required to maintain these two levers in running position, especially in the case of the throttle, as he would have to exert considerable force to hold it open against a device that would have any value as a positive closing mechanism. The conditions under which an engineman works at present are not what might be termed restful. There is continual jar and pound, as a locomotive compared to a coach rides about as easily as a hay wagon compared to a limousine. If in addition to this a man were compelled to maintain a steady and unremitting pressure for a period of from three to seven hours, the average length of a passenger run, it would be almost if not quite beyond human endurance. Los Angeles, Oal. J. B. Wells. Irrigation Supplementing Water Power A New Joint Use for Our Canals. To the Editor of the Scientific American: In order to get at the power to be obtained from waterfalls, a height of 10 available feet is taken as a convenient basis to calculate any power from. One cubic foot of water, weight 62% pounds, falling 10 feet produces 625 foot pounds. Requirement for one horse-power, 33,000 pounds divided by 625, gives 52.8 cubic feet, required, for one theoretical horsepower, per minute. But as wheel efficiency is seldom over 75 per cent, we add one-third to 52.8 or 70.4 cubic feet of water, which is sufficient to cover 844 square feet, or one-fifty-second of an acre. So that the, amount of water required to produce one horse-power 52 minutes would cover one acre one inch deep, if none was wasted. But as the waste is considerable, let us assume that it requires two hours to cover one acre one inch, or in ten hours the water required to yield one horse-power would cover flve acres one inch deep. Now, as power can be generated, even in small units, for not over 20 cents per horse-power for ten hours, and in large units for much less, we have one inch of water costing four cents per acre, when for some crops it would be worth easily fifty times that, and others much more, as this water is warm rain water, and far superior to well water for irrigation purposes. In view of the above statements, can we not safely conclude that our canals, or at least such sections of them as are favorably located, should be maintained for irrigation, which as explained below, may also reduce their value for water powers but little? In many cases the canal is so located that all the water to be spared can naturally flow onto the lands, while in some cases a ditch to the next lock may be required to get the water high enough. The very favorable results of some small irrigating experiments in our section, I think, will fully justify our valuable experiment stations in examining availably located lands, and in preparing necessary information as to suitable crops, fertilizers, sand mixing to lighten heavy soils, etc. That may enable the great increase in crops due to irrigating to be fully realized. Now, if the power man, who is usually short of power, either for manufacturing or to sell electrically, will arrange his water wheels, etc., so as to give him the full power of the fall for say the best six months of the year, and will put in engines enough to develop the same amount of power, to be used when there is not water enough for all needed, which if for lighting will be less when water is lowest, he can have water power for all his needs for six months or more, and for nearly all the rest of the time part of the water, in fact most of it. Where the water is used only for ten hours for power, the irrigating can be done, at night, as in the West. So that the power man can be in a better position, after the first cost of engine installment is paid, than if entirely dependent on the water power, as he will not only have increased power, but also power that can absolutely be depended on. I trust that the above will be, in some way, a suggestion that will be a benefit to the community and the State in making use of its canals. Dayton, O. J. H. Stevens. Automatic Stability in Aeroplanes—A Suggestion To the Editor of the Scientific American: Would you allow me to express. through your valuable paper my opinion on the possible solution of the automatic lateral stability in flying machines? The many devices designed and tried out to maintain automatic stability have as yet not met with the success which would be desirous. All further progress and the commercialization of aerial navigation depend upon the appearance of such a device. A suggestion of my own may lead to a possible solution of this problem. I describe my idea with a view of encouraging constructors of flying machines to experiment in this direction. My automatic lateral stabilizer consists of fins, constructed of a light framework of wood or metal covered with a suitable fabric. These fins are hinged under the surface, at the extreme ends of th© plane (win", tips) and can swing to both sides. When swinging inward such a fin can move until it lies flat under the surface, but toward the outward it is prevented by a strap froTh. swinging farther than 45 degrees. The function of the device may be conceived to be as follows: When the plane is in motion, and as long as it is not influenced by a force caused by a side wind, the fins will be retained in a vertical position. But when the wind strikes the plane at an angle to the direction of motion, the fin nearest to the side from which the wind is coming will be laid flat under the surface of the plane. At the same time the. fin on the opposite side swings outward to an angle of 45 degrees to the plane, and will present a resistance corresponding to the natural resistance on the windward side. This arrangement . seemingly works well when straight flights are made, and even in turning it seems likely to do all the banking required; but to straighten out the aeroplane after or at the termination of the turn, it may be found necessary to have recourse to the operation of ailerons. Even if this device needs at times to be supplemented by ailerons, it would do much to relieve the operator of an aeroplane of the continuous strain which the attendance of a lever mechanism to operate the lateral and the longitudinal stability means. One of the main requirements would be to have the size of the fins in the right proportion to the plane which it serves as equalizer. Such a device could be used on aeroplanes of all constructions, and to simplify the attachment of these fins the last five or six ribs on both sides should flatten out gradually, so as to make the extreme ends of the plane nearly flat. Chicago, III. Ewald Steinhaus.