Rensselaer Journal, Volume 11, Number 34, Rensselaer, Jasper County, 30 January 1902 — NOTES ON SCIENCE [ARTICLE+ILLUSTRATION]

NOTES ON SCIENCE

With some refreshing exceptions, popular science continues to be more popular than scientific. For instance, here is a late bit of gossip about dynamo design: "It will be jiews to many that dynamos have gone out of fashion. Those who belong to the smart set of the electrical world talk now of generators. Generators—that is to say, our old friends the dynamos—have ceased to be specially interesting because, like the fiddle, they have reached perfection. To those who have not paid attention to the matter this may sound like an exaggeration, but, as a matter of fact, there is not much room now for improvement in electrical machinery. Everything is becoming fixed and standardized —a sure sign of maturity. The imitations and conditions are well understood, and only a few more revolutions are possible, and none probable.” This is from a handsomely illustrated and printed article in one of the ten-cent monthlies. One can detect a certain disguised flavor of truth in this glib recital, although the statement that "only a few more revolutions are possible, and none probable,” is puzzling; but, after all, how misleading the whole is! Generators have hardly reached perfection, and standardization of apparatus does not mean stagnation by any means. Watch-Winding Indicator. The object of the invention illustrated below is to indicate at a glance when it is time to wind a watch or clock, without the necessity of testing it, and also to insure regularity in winding. Jewelers say that a.watch must be wound at regular intervals to keep the best time, but it is seldom that the owner attends to the winding at the proper time, simply because there is nothing to call his attention to the fact that the watch should be wound. The indicator here seen consists of a circular plate of metal, mounted loosely on the shaft which carries the hands. A slot is cut in the dial and the figures on the indicator are arranged to present themselves in the opening as the plate revolves, the actuating mechanism being the spring which runs the hands of the clock. While a glance at the dial will show the number of hours which have elapsed since the watch or clock was last wound, the device is

arranged to particularly attract attention as it nears the winding hour, three or four of the highest numbers on the indicator being in red or some other prominent color. The inventor* is John A. Saunders of Poindexter, Va. New Safety Lamp for Miners. A young New York electrician, M. R. Hutchinson, has recently invented a device which ought to prove a special boon to miners. It is an electric lamp and is to be carried in the cap, just as an ordinary miner’s lamp is carried, the electric current to be supplied from a storage battery. The battery is less than three pounds in weight, and is good for eight to ten hours’ steady work. It may be carried in a pocket. Indeed,. Mr. Hutchinson has built the batteries in such shape that they fit snugly into a pocket. The practical result of the use of such a lamp as this is that the danger of death from fire damp is removed, the valuable oxygen of the air is not burned up as it is by the use of an ordinary lamp, the whole apparatus is clean and compact; .moreover, the light given is much better than that of any other device used in this way. The lamp should be introduced into every mine where men are obliged to work far awny from light and good air. The device should also find a place in cave exploring, well digg;ng or any underground work.

Mortality in United State*. A recent bulletin of the United States census compares the mortality of 1890 and that of 1900 and shows that there has been a diminution of something like 10 per cent in the death rate. In 1890 the average longevity in the United States was 31.1 years; in 1900 it is 35.2 years. The increase is 13 per cent. This is the conclusion, at least, sd far as cities of over 8,000 Inhabitants are concerned and it represents the facts for the whole country approximately. In 1894 245 persons died of consumption in every 10,000; in 1900 only 190. The case is similar, though not so marked, for other diseases—diphtheria, bronchitis, typhoid, cholera infantum and the like. The main causes are a perfected hygiene of towns and the progress of medicine. Pneumonia. however, claimed 192 victims per 10,000 in 1900 to 187 in 1890. Extraordinary Engineering Feat. Out in the center of the busiest part of one of the busiest harbors in the world, in the midst of a tidal current the fastest to be found in any great seaport, a feat is being performed that at one time was considered practically impossible. For the purpose of learning the nature of the formations un-

derlying the East river, New York, where the tunnel in Brooklyn is proposed to be built, bearings are being made under extraordinary conditions. Following plans throughout in their minutest detail, a contracting company has succeeded in sinking diamond drills four points deep In the rock formation underlying the river. Work on a fifth boring is being pushed, and unless some unforeseen accident occurs the other two borings called for under the company’s contract will have been finished within the next two weeks. Power Transmitter. In the Illustration is shown the pow-er-transmitting device recently designed by Charles G. Armstrong of Chicago, 111., the object of the invention being to drive machinery by employing magnetic lines of force. The Inventor states that he is enabled to transmit the rotary motion of a driving wheel to a driven wheel without actual contact and without any mechanical wear and tear

or noise resulting while the machinery is in motion. The driving wheel is provided with magnetic colls arranged around the periphery, with means for energizing a portion of the coils at a time.

This is accomplished by passing the electric current from a generator through the upper spring contact arm into the two or three coils immediately below, and allowing it to pass out through the lower arm. In this way a strong pull is exerted on the projecting spokes of the larger wheel on the side toward the energized coils, with absolutely no attraction after the center' is passed. The tendency Is for the magnets and attracted spokes to continually approach each other, and as fresh, magnets and spokes are constantly coming under the drawing power the wheel continues to revolve as long as the energizing current is supplied.

Reminder of Duty.

Drives Without Contact.