Rupturinga Current of 800 Amperes at 13,000 Volts INa paper recently read before the Pittafield-Schenectady Mid-year Convention of the American Institute of Electrical Engineers, D. Merriam discussed the problems of oil-break circuit breakers. The oil circuit breaker interrupts an electrical circuit in oil without producing abnormal disturbances in that circuit and also confines the destructive arc to a small volume, thereby preventing its spread to adjacent apparatus and enabling the oil circuit breaker to be safely placed in any convenient location on the switchboard or in the power station. Air break circuit breakers, owing to the large vicious arcs which they produce, are unsuited for general alternating current circuit breaking applications. The illustration herewith shows an arc drawn by one of these devices when opening a circuit carrying 800 amperes at 13,000 volts. This arc, one of many observed, was about 180 inches long and rose 140 inches in the air while the same circuit ruptured in oil produced an arc only 9 inches long and with no external disturbance. Pneumatic Spring for Automobiles WE illustrate herewith a pneumatic cushion which has with considerable success during the past year been used to take the place of springs in automobiles, and which is now being tested on the commercial vehicle. The cushions consist of rubber bulbs, each with an outlet through the neck at the top, connecting with a good-sized air reservoir. The cushions at the front have a separate air tank from those at the rear. A pressure of but 27 pounds is used in the front cushions, which are 8 inches in diameter, whereas 43 pounds to the square inch is the pressure used in the rear 10-inch cushions. This pressure is sufficient to support the weight of a 31f2-ton express truck, fully loaded. In the future, a single bulb will be used in place of each spring, these bulbs being 9 inches in diameter in the front, and 12 inches at the rear. According to the superintendent of the express company which has been testing these cushions on one of its trucks for the past two months, the cushions absorb the road vibrations of the running gear and cause the wheels to cling to the ground, giving better traction. The result is twofold—a decided diminution of the wear and tear on the engine and transmission, and longer life of the tires because they do not bounce so much. The saving on the machinery and tires is estimated to be as much as twenty-five per cent in both cases. . Another good point of the cushion spring is that it will not crystallize and break as steel springs frequently do. This is a decided advantage, especially with a commercial vehicle, where the breakage of a spring generally causes great delay. A Museum of Speech FOR more than a year, a Parisian professor, Mr. Ponge, has been engaged in creating a very original museum, for the collection and preservation of records of the human voice under all of its manifestations. In this museum of speech there will be in addition to the original records, wax copies and microphotographs of the contour and relief of characteristic phonograms; also studies of the organs of speech as well as photographs of speech (Marage process). With the help of these data, the museum of speech will make a phonetic chart of French speakers. Thanks to these files it will be possible to notice almost imperceptible differences between the same words in the patois of two neighboring villages, or of two successive generations. Just now Mr. Ponge is using the phonograph to preserve the children's songs and the cries of the street as well as the speeches of the great orators, the sermons of the celebrated preachers, the arguments of illustrious members of the bar, etc. One of the photographs shows him at work in a school among the children playing and singing a child's song. Another of our views shows him in the street recording the cry of an asparagus vendor. 'He has a fertile field for work among street criers. There is the hawker of straw goods, the mender of chairs, the china and porcelain merchant, the cask maker rolling his barrel as he goes along, the glazier and other small merchants whose “speech” lie records for minute study. Setting a Watch by Wireless Time Signals NOW that time signals are being sent out from the Eiffel Tower periodically, amateur wireless telegraphers have seized the opportunity to set their watches by means of these signals. Obviously, this form of signal has its advantages over that of the time ball in common use here. The signal is sent out broadcast and any one may receive it in his own home, not only in Paris, but in suburbs and neighboring towns. The receiving instruments of wireless telegraphy are very simple and inexpensive, and any boy can make them out of materials at hand, practically the only expense being that of a good telephone receiver. The accompanying photograph shows a rather more elaborate set of instruments than is absolutely necessary, and the operator, with telephone to his ear and watch in hand, is waiting for the signal from the Eiffel Tower. A system such as this should do much to set a standard of time over a large area at but little cost. Mesmerizing Lobsters BIZARRE information may occasionally be gleaned from the most serious scientific literature. The title of the Report of the Northumberland Sea Fisheries Committee for 1910-11 suggests routine statistics on trawling and seining, sea temperatures and salinity, plankton and the like; hence it is somewhat disconcerting to find therein more or less valuable directions as to the best way to mesmerize lobsters. “The usual method (we quote from Nature) is to hold the lobster head down, with the claws arranged so as to form a support with the rostrum, and to stroke it rapidly with the tips of the fingers,” i. e., to stroke the back of the carapace, or shell covering the crustacean's head and thorax. “In about a minute the lobster succumbs, and remains without movement in this position for a variable period. In order to see whether the reversed position, as driving the blood to the head, was essential, a lobster was treated in the horizontal attitude, and so successfully that it remained without movement for three hours. A Norway lobster subjected to a similar treatment was quiescent for fifty-minutes. A lobster can be put to sleep on its back.” Other crustaceans are amenable to the same treatment. “The crab goes to sleep usually in the tucked-up condition, and may be left in the natural position or on its back. They all recover when disturbed; but the recovery of the lobster appears to be quicker if the under surface of the cephalothorax is disturbed. Placed in sea water' lobsters recover immediately, but in one such case a crab took ten minutes to come round completely." The process is beautifully simple, and— such are the vicissitudes of life—one can never tell when the foregoing information might “come in handy."
This article was originally published with the title "Curiosities of Science and Invention" in Scientific American 105, 25, 553 (December 1911)