OCR Text |
Show M I POPULAR SCIENCE I which answers as a seat for the person per-son controlling the motor and steering the boat The motor casing, is cut away in the picture to show the meth-od meth-od of mounting the propeller shaft and j connecting the motor. Of course this boat is not intended to compete with the high-speed and higher-priced craft which the modern , boat builder is now able to product, but it is intended for cruises or fish- . , ; ing trips about the rivers and lakes of the country. To place the mechanism mechan-ism in position on a boat it is only .... necessary to store away" the, batteries and gasoline reservoir ,' beneath the ' seat and suspend the .motor1 casing j over the stern by the hooks and clamps- provided for the purpose. The inventor is Irwin R. Miller of St. Paul, Minn. j I ! Simple Fountain Pen. The fountain pen here illustrated by a drawing from the Scientific Anriri-ran Anriri-ran was designed with a view of producing pro-ducing an effective yet inexpensive instrument, which could be readily filled with ink, and which, when in-inverted in-inverted position in the pocket, would prevent leakage of the ink. The pen consists of an ink holding barrel, pointed at one end and provided at the other with a bulb, into which a capillary ca-pillary tube projects. This tube forms an opening in the pen, through which air can enter the chamber when the pen is in use and permit an even flow of the writing fluid through the small opening at the, writing point. To fill the pen the point is inserted into the ink, -and suction is applied to the opposite end of the barrel. . To prevent too rapid ' feed of the ink ' through thp . channel, a packing of Pocket Telephone. 7 '' This is a pocket telephone designed for common battery circuits. This telephone makes quite an improve-' ' ; ment in the portable set variety, and is a' very neat and compact appearance. appear-ance. The transmitter and receiver are arranged ar-ranged In series, and made of a re- , sistance to coincide with the regular ' telephones in( use on any system. When used as a testing set, the flexible flexi-ble wires are provided with the terminals ter-minals in the form of spring clips, so that they may be readily connected connect-ed to the locknut strip of a terminal head, or to any point of the line as desired, the mere attaching of the clips giving the necessary call to the exchange in the same manner as when the receiver hook is raised on a regular telephone. A Simple Fountain Pen. hygroscopic material, such as absorbent absorb-ent cotton, is placed in the barrel to be filled on the application of a vacuum, will also retard and control the flow of ink through the channel in the writing point. Philadelphia Ledger. Single Rail Overhead Railway. A project is on foot in London tfl build along the Thames for a distance of about eight miles, from Southward bridge to Barnes, an overhead single rail railway similar to that now iD successful operation at Elberfield, Prussia. The accompanying picture, showing how the structure would look, is from the London Mail. The build-An build-An Aerial Station on the London ing of this road would cost, it is estimated, $25,000,000, and the time required for its completion would be about five years. Passengers would reach the railway by elevators established estab-lished at each of the numerous bridges over the Thames, which are, of course, the main highways of traffic, and if New Naval Weapon. Admiral Makaroff of the Russian navy, has invented an instrument which, it is said, will play a great part in any future submarine warfare. The .instrument is known as a radioson, and several successful tests have already al-ready been made with it at Cronstadt. By connecting lt with the military telephone tele-phone the approach of torpedoes to Cronstadt was clearly heard by an officer of-ficer in the war department at St Petersburg. The main function of the instrument consists in pointing out the exact location loca-tion and registering the speed of torpedoes, tor-pedoes, and experts claim that nothing noth-ing can prevent it from doing this work properly. It will reveal, they say, the presence of the enemy Just as well during the most stormy night as during a calm day, and it will also, if desired, destroy the torpedoes either automatically or at the will of an official, of-ficial, who may be several miles away. The news of this invention has caused a sensation in naval circles in Europe, and it is hoped that further tests will soon be made with it BallooA Voyages Over Oceans. La Nature gives an illustrated account ac-count of the latest niethods for controlling con-trolling the flight of balloons in sea voyages. In order to prevent the balloon bal-loon from being depressed by a shower of rain its top terminates in a cone. Instead of trailing a single rope there is a system composed of a trailer floating at the end of a long rope behind the balloon and a balance weight hanging in the water by a shorter, nearly vertical, rope, the resistance re-sistance of the la?txr body being necessarily ne-cessarily less than that of the former. The sea itself furnishes an inexhausti- Overhead Railway. these bridges should not prove numerous numer-ous enough the company will erect others. ble supply of ballast and this can be drawn up to a cylindrical reservoir, suspended above the balance weight, a suction hose being used for filling the reservoir. Two deviators are employed em-ployed for directing the course of the balloon, one of which serves for angles an-gles of about 30, the other for angles an-gles as great it is said as 70 or 80. Mexican Substitutes for Cotton. The attempt to utilize two nativf delicate fibres as a substitute for cotton cot-ton in many of its uses seems to be progressing, says Modern Mexico. The plants produce a cotton of two classes; class-es; the smaller one gives a coffee-colored seed and grows and multiplies mul-tiplies without special care all the year round; its fibre is thicker than that of the common cotton. The seed of the other plant is of a light blue color; this plant requires special cultivation and irrigation, without which it will give one crop in the year; the fibre Is finer than the other, and as fine as the finest cotton. Hilario Cuevas of San Luis Soyatlan, in the Mexican State of Jalisco, who first experimented experi-mented with these two plants, is distributing dis-tributing seeds all over the hot lands, for which it is most suited. Propeller for Small Boats. It is only natural that the owner of a rowboat should at times desire a motor launch, especially when on a long-distance pull on a warm day, and yet the expense of a new boat, with engine and machinery, places it be- Improving Steamship Screws. A phenomenon known as "cavitation" "cavita-tion" has lately come to be recognized as one of the most important causes of loss of efficiency in the driving screws of steamships. When the velocity of the screw is increased above a certain limit a cavity is formed in the water inside which the screw revolves, and a further increase of power then causes no increase of the ship's speed. Mathematical investigation, tested by practical experiments, has shown that cavitation can be avoided by preserving preserv-ing a certain ratio between the resistance re-sistance and the -propelling surface concerned. Upon this principle tha speed of some vessels has been greatly great-ly increased by simp.y changing heir driving screws. Gasoline Motor Attached to the Stern. yond the reach of the majority of rowboat owners. In this illustration is shown an apparatus ap-paratus which may answer the purpose pur-pose fully as well as a new boat, and at far less cost. It is nothing less than a gasoline motor so arranged that it can be secured to the rear end of a small boat, with the fuel and electric batteries stored in a casing |