Page:Popular Science Monthly Volume 86.djvu/622

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THE POPULAR SCIENCE MONTHLY

engines, the condenser, and later the double-acting engine. The development of the engine was advanced by Cugnot, Evans, Hornblower and Murdoch; a model of the latter's engine is on display in the museum.

Richard Trevithick made the first engine to run on rails in 1803. It has been claimed that he copied the stationary engine built in 1800 by Oliver Evans, an American, which was later attached with wheels to a scow and propelled it by steam through the streets of Philadelphia in 1804. This curious creation called the "Oruktor Amphibolis," was the first motor car to run on American soil.

A model of Trevithick's engine is to be seen in the National Museum, as is also the model of the engine employed by John Stevens in 1825, and his original tubular boiler. Other models illustrate nearly all the types which began to put in their appearance soon after 1828, when the "Stourbridge Lion" was built in England and shipped to America, where it was the first engine to run on full-sized rails. The museum possesses not only the model of this historic engine, but the original engine itself. The other original full-sized locomotive to be seen in the museum, is the "John Bull," built by George Stephenson and Sons, of England, and shipped to America for use in 1831 on the Camden and Amboy Railroad. This old relic of early railroading in America made a round trip under its own steam in 1893 from New York to Chicago, where it was exhibited at the Worlds Columbian Exposition. Among the models of early and historic locomotives are: George Stephenson's "Rocket" built in 1829; The B. & O. engine "Tom Thumb," built by Peter Cooper in 1829; the grasshopper type engine, "Arabian" of 1831; the "Best Friend" used in 1830-31; Baldwin's "Old Ironsides" constructed in 1832; the "Sandusky" built in 1837, and models of engines made by Asa Whitney, in 1840, and G. A. Nicholls in 1848. Besides the two locomotives and the numerous engine models, there are in the exhibit, coach and car models, sections of rails, spikes, wheels and models and parts of valves, pistons and other early patented accessories pertaining to locomotives and railroads, all of which go far toward completing an absorbing chapter of graphic history in connection with this interesting and important commercial development.

 

THE IMPROVEMENT OF ACOUSTICAL CONDITIONS

At Western Reserve University the ceiling and walls of the Amasa Stone Memorial Chapel have been treated for the purpose of perfecting the acoustics of the building. The chapel is one of the most beautiful Gothic churches designed by Henry Vaughan, of Boston. Unfortunately, however, as in many lofty structures, the acoustics have not been satisfactory. A series of experiments with sounding boards was made by Professor Frank P. Whitman, of the department of physics of the university, in the hope of improving conditions. Careful data obtained by Professor Whitman showed that the effect of the sounding boards was almost negligible. Acoustical experts were called upon to study the problem.

The difficulty experienced in the auditorium was found to be what is technically known as reverberation, in excessive amount. Owing to the size of the building and the consequent long distance between reflections of the sound from one surface to another, and also owing to the hard and unyielding building materials which cause only a small percentage of the sound to be absorbed at each reflection, the result was that every sound generated within the chapel persisted for a number of seconds after the source itself had ceased, thus causing great blurring and confusion in spoken addresses, owing to the overlapping of the sounds of consecutive syllables. This phenomenon has been the subject of extensive study by Professor W. C. Sabine, of Harvard