6i8 



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 dis 

 play in the museum. 



Eichard Trevithick made the first en- 

 gine to run on rails in 1803. It has 

 been claimed that he copied the sta- 

 tionary engine built in 1800 by Oliver 

 Evans, an American, which was later 

 attached with wheels to a scow and pro- 

 pelled it by steam through the streets 

 of Philadelphia in 1804. This curious 

 creation called the " Oruktor Amphi- 

 bolis, " 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 orig- 

 inal tubular boiler. Other models illus- 

 trate 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 his- 

 toric 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 Amer- 

 ica made a round trip under its own 

 steam in 1893 from New York to Chi- 

 cago, 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 "Whit- 

 ney, in 1840, and G. A. Nicholls in 1848. 

 Besides the two locomotives and the nu- 



merous 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 loco- 

 motives and railroads, all of which go 

 far toward completing an absorbing 

 chapter of graphic history in connec- 

 tion with this interesting and important 

 commercial development. 



THE IMPEOVEMENT OF ACOUS- 

 TICAL 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 im- 

 proving conditions. Careful data ob- 

 tained by Professor Whitman showed 

 that the effect of the sounding boards 

 was almost negligible. Acoustical ex- 

 perts were called upon to study the 

 problem. 



The difficulty experienced in the audi- 

 torium was found to be what is tech- 

 nically known as reverberation, in ex- 

 cessive 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 

 liuilding materials which cause only a 

 small percentage of the sound to be ab- 

 sorbed at each reflection, the result was 

 that every sound generated within the 

 chapel persisted for a number of sec- 

 onds after the source itself had ceased, 

 thus causing great blurring and confu- 

 sion in spoken addresses, owing to the 

 overlapping of the sounds of consecu- 

 tive syllables. This phenomenon has 

 been the subject of extensive study by 

 Professor W. C. Sabine, of Harvard 



