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About Omaha daily bee. (Omaha [Neb.]) 187?-1922 | View Entire Issue (May 8, 1904)
I S w IE lEll i .1 i I? r r tlsLlIi J4L ,NITKD STATKS CONSUL. CUKN- u TlIKTt, stationed lit Frankfurt. Germany, sends to the Depart ment of Commerce a description of an automatic device for stop Ml ping trains. Tho device constats of a con tact apparatus which Is so placed between the rails that a plate f;istencd to the lowest part of the air brake pipe under the tender Is touched in passing over it. The result Is the opening of a valve and the applica tion of tho air to the brakes. The device Is put up like a pendulum, attached to which fc a counter weight, so that the apparatus, which In a vertical position closes the line, an be turned down by the watchman In the nearest tower and the lino can In this way be opened. The Interior of the head of the apparatus on tains a shell made of Insulated material, connected with three electric wires, well Insulated from each other. The center wire is connected with a brims plate, while at tho ends of the other wires are two brans contact springs placed opposito to each ther. On each side of the brass plate are brass pegs with steel head adjustment. By means of springs both pegs are kept In close proximity to the brass plate. When the line Is dosed uid the brass plate con nected with the air brake pipe hits the bead of tho contact apparatus the plate Is thrown back, thereby opening the air brake. At the same time tho peg on that Side is forced Into the interior of the apparatus. Closing the circuit and ringing the bells which are connected with the wires. The report does not Btate any facts regarding tho suddenness with which the train is topped, but presumably it partakes of all the elements of an extreme emergency ac tion by the engineer. Some critics declare that tho presence of such a device would tend to make the englneman careless, as he Would know that his parsing a signal at "stop" would not result seriously. De creased vigilance, however, has also been advanced as an argument against the block ignal system. Telautograph?. In the Thyslkallsche Zeltschrlft Dr. A. Korn describes a new receiver for tclauto graphy and the telegraphic transmission of half-tono process blocks. In the transmit ting apparatus the writing or the po'nts and lines of the half-tone block are formed liy a nonconducting ink on a Fhect of metal foil. This is wrapped round, the surface of a cylinder which is rotated with uniform angular velocity. The electric current is transmitted by means of a metal pen which moves forward 0.01 inch In each revo'utlon. In the receiving apparatus tho cylinder is rotated with an angular velocity greater by 1 per cent than in the transmitting appara tus, and at the end of each revolution It Is mado to await a synchronizing signal by Which it is restrained. The impression at the receiving station Is produced on sensi tized paper by a small electric lamp or vacuum tube, which by means of a suitable relay for Tcsla currents Is made to glow whenever tho pen at the transmitting sta tion passes over a nonconducting portion cf the picture. The paper is illustrated by specimens of handwriting transmitted by this method. Electricity In the Navy. Some interesting facts are contained la the report of Lieutenant Harry George, TT. 8. N., Inspector of electrical appliances. Among other things it is shown that the sum of $376,904 was expended during the last fiscal year upon the Installation and repair of electrical appliances on ship board, and $212,830 on the manufacture and repair of electrical apparatus and appl ances In navy yard shops. Alterations, ad ditions and repairs to tho electrical appli ances of 11S naval vessels were made during the last year. A portable searchlight has been designed for use in connection with coast defense districts and the occupation of advanced naval bases, in general, the apparatus con sists of two units, each mounted on broad threadwheels, suitable for operation In a rough country, and so constructed that it can be readily assembled or disassembled for transportation In ships' boats. During the last year tho Bureau of Kqulp nient of the Navy department has acquired two sets of the DucreHet loud-speaking tele phone, marine type, extensively used In the French navy. This apparatus, together with a set of the Oraham Instruments, English navy type, will be tested In com petition with the Bell and other Instru ments of American manufacture and In stalled on board ship for further observa tion. A new system of battery fire control has been designed during the year to meet tho requirements of the bureau of ordnance. In this system the guns are divided into groups instead of by divisions, as here tofore, each group including all guns of practically the same nnture and having the same arc of fire. The system pos sesses great flexibility and enables sep arate and distinct orders to be transmitted simultaneously to the various groups of guns. The school at the New Tork navy yard for the Instruction of enlisted men for the rate of electricians, with a view of detail on shipboard as dynamo tenders and for the care of electrical appliances, lias been successfully conducted during the pnst year. It will soon be moved Into more suitable quarters, with additional ap pliances, where it is anticipated It will bo still more cfllcicnt. Novel Hnt Trap. The latest and most efficient as well as the most humane method of getting lid of a pest of rats is by the use of electricity. Such, at any rate. Is the opinion of the proprietor of a largo grain warehouse In Rochester, N. Y., where the rats until re cently were so abundant that their drpro dations were an actual source of financial loss. Since the Introduction of scientific methods, however, the rats have been killed off fo rapidly that within a short time they will ho practlcaJly extinct. When the rats first begun to overrun this particular warehouse tho aid of their time honored enemies, cats, was first called in. Tho cats meant well and were ener getic. But they could not follow the rats down their holes, and the rodents were so sly, as well as numerous, that' It was soon evident cats could not solve the problem of getting rid of them. Traps of various kinds were then tried. At first they worked well. But after a little time tho rats camo to understand and avoid them. The same proved true of poison. In the mean time the rats who had first selected the grain warehouse as a place where an easy living could be procured, had evidently Informed their rat friends, and these called in others, until It seemed as if the most of the rats In that part of the state must have estab lished headquarters In that warehouse. Then a clerk with an Inventive turn of mind tackled and solved the rat question. The warehouse Is lighted with Incandescent electric lights, which, however, are seldom used at night. First, the clerk placed a flat piece of copper on the floor in one of the corners of the building, and a wire was run to It from the Incandescent light circuit. On this copper plate was placed a large and appetizing ploco of cheese. Then a second copper plate was placed on the floor, almost, but not' quite, touching the first copper. The return wire of the In candescent light circuit was connected With this second plate. The cheese, of course, was In full view on tho floor, and nothing could have looked more innocent. But to reach it a rat would first step on the copper plate con nected with the return wire. flo far noth ing would happen to disturb the peace of mind of his ratshlp. Ills next move, how ever, would be to plaoe his forefeet on copper plate number one, on which the cheese had been placed. The Instant the front feet of the rat touched this piece of copper, as his bind feet would still i.e. en tho second copper, he would complete the electric circuit. The current would tdioot through his body and ho would drop dead before he had time to utter a squeak. There was nothing about the contrivance to Indicate a trap, even to the oldest and wisest rat. The cheese was In plain sight, and apparently easy to get, and by Its smell attracted rats from all over the ware house. The whole arrangement looked so Innocent that even the sight of the bodies of their predecessors did not frighten awny tho hungry rats. On the morning after tho "rat electrocution trup" was first tried, over a score of dead rats were found. Tho next evening half a dozen similar traps were set, all meeting with the success of tho first'. It was plain that the rat ques tion was settled, so far as that warehouse was concerned. New York Tribune. " Simultaneous Telegraphy. In 1SS2 Van Hyssclberghe an ill-rewarded Belgian llrst proposed tho conjoint use of telephone circuits for both telegraphy and telephony simultaneously, and initiated In geniously the use of comjKWdto circuits for such purposes. At tho present time a large number of long-distance telephone circuits are used for telegraphic purposes over and above their regular telephonic duty. Tho general and striking facts con cerning compoHite circuits are fully set forth In the very Interesting article by Mr. U W. Stanton. Broudly speaking, such a circuit passes both low-froqueney telegraph Impulses and higher-frequency telephone currents, receiving these In re spectively selective branch circuits. It is curious to note that the signaling or call ing telephone currents ordinarily belong to the low-frequency class, and that con sequently special precautions are sometimes necessary to keep theso telephone currents from interfering with the telegraph. Yet another kind of composite circuit not com ing within the scope of tho article is the conjoint use of telephone receivers with telegraph apparatus under the name of the phonoplex system, which Is In fairly ex tensive use. In this arrangement high frequency Impulses are used to actuate the telephone receivers for telegraphic Instead of telephonic purposes. Those technical aspects and considerations have their value and importance, but they seem to us nln lmlzod, comparatively, by tho commercial possibilities, outlined briefly by Mr. Stanton at the conclusion of his very suggestive article. Tho details given by him as to the amount of work already done In the application of the system will astpnlsh most people, including not a few familiar with the twin telegraphic and telephonlo arts. It ls true that the figures quoted deal with what is going on In one section of tho independent telephone field, but there could be a good deal said from the Bell side also, although the management has so far preferred to maintain an ex uberant reticence as to what it is doing In that respect. Printing Without Ink. While Investigating a process for letter press printing by electrolysis without tho uso of Ink (an extension of Bain's tele graphic printing) Mr. Charles It. Darling of London found that the final results of electrolysis when the electrolyte forms only a thin film often differ materially from those observed In an ordinary cell. In the course of his experiments, which he lias lately brought before the Farady so ciety for discussion, Mr. Darling used a carbon or metal plate (It was Immaterial), which formed the anode; on this was placed nn Impression pud, consisting of some sheets of moist blotting paper; upon this was the trial sheet, carrying tho electro lytic film and on this the cathode type or coin. Voltages from six to 200 were em ployed. It was requlslto. In order to obtain a clear Image of the type, to use a certain minimum strength of solution. Tho tlrst ex periments were mailt1 with saline solutions; allver nitrates gave a clear, permanent black linage of the type, but tho paper of course darkened on exposure; copper sul phate and nitrate yielded Images that fiided after a time; the same unexpected result occurred with lend, mercury salts and bis muth. The best linages were obtained with manganese salts. Those consisted of tho oxides or hydrates, end were thus quite permanent ; all purely metallic deposits, ex cepting silver, disappeared after a time. In the case of iiousalluo solutions, the paper, which might consist of asbestos or pure Swedish tllter paper soaked In distilled water, acquired the properties of an exposed photographic plate, and on treating with a silver suit and developer a perfect linage of tho cathode wius lt:Uned, even after a long interval. Mr. Darling showed produc tions of such elerographs to his audlenco. The latent linages are not duo to hydrogen peroxide, nor to metallic compounds as they occur with carbon electrodes, but they re side In the surface of tho paper In contact with or toward the cathode. They aro abcrlbed by Mr. Darling to a class of phe nomena that have been Investigated by Bonn, and termed "tho response of Inert matter to electrical stimulus." Ho Is of opinion that they are probably tho result of some state of strain set up in tho film by the current. Lessons of Paris Tunnel Disaster. A long editorial, summarizing und criti cising a report of the technical committee which had Investigated tho disaster on the Paris Metropolitan railway in August lust. Is printed la tho London Klectiician. A summary is first given of tho causes of the accident, and the lessons from the disaster aro summarized for the prevention of Mini lur accidents. The Investigating technical committee lays the greatest stress on tho requirement that it should bo pestiblu for the train staff to cut tho current off the conductor rail at any point. For this pur pose It Is suggested that the rail should be cut up into u number of separately fed sec tions, such that not more than live or pis trains can be on any one section, and that every train shall carry a "short-circuit bar," which can be dropped across the cen ductor und running rail In caso of need and so actuate the circuit-breakers e-ontrolling the section. The committee also urges that the lighting of the stations and tunuela should be provided from a number of sources, some of them entirely Independent, not only of the traction supply, but e ven of the company's generating and substa tions. It appears that the committee con siders that tho nonlntlammable ear Is at present hardly attainable, so that the short circuits must be expected, and when they do occur sumo risk of lire Is unavoidable. Tho writer of the editorial thinks that the committee has Inverted the propter order of the measures reepilred and that the essen tial condition of Bafety would be to design and equip the motor cars In such a way that Ignition of combustible material Id hardly possible. "With rubber-ceivercd ca bles boxed In with wnexl, a shoe that can not bo readily lifted from the rail, and circuit-breakers or fuses set feir teo heavy a current. It is conceivable that a short-circuit may put a car into a blaze in a few seconds and constructions carrying sin hj risks must bo avoided." It is also pjinted out that from what happened It appears that neither trainmen nor the station staff had been instructed bow to deal with an electrio lire.