360 ANNUAL REPORT SIVHTHSONIAN INSTITUTION, 1961 



THE MANLY-BALZER ENGINE 



The second of these engines to power an aircraft was redesigned 

 and rebuilt by the American Charles M. Manly. It was first used in 

 an aircraft during the autumn of 1903. 



From 1887 to 1896 Samuel Pierpont Langley, Secretary of the 

 Smithsonian Institution, had conducted a series of experiments with 

 heavier-than-air craft models. By 1896 his steam-driven ones had 

 made repeated flights of from one-half to three-quarters of a mile. 

 President McKinley learned of these successes and during 1898 

 authorized the expenditure of $50,000 for the construction and testing 

 of a man-carrying heavier-than-air flying machine. Before agreeing 

 to attempt the work for the War Department, Langley had made a 

 search for a reliable builder who would undertake to construct a gas- 

 oline engine of not less than 12 horsepower, to weigh not exceeding 

 100 pounds. Wliat then seemed to be a sound contract had been 

 entered into for one engine which would meet these requirements. 

 The first builder was soon found to be unreliable, and after a more 

 extended search, a contract was entered into on December 12, 1898, 

 with Stephen M. Baker, an engine builder in New York City. He was 

 to furnish an engine meeting the above-mentioned requirements by 

 February 28, 1899. Since it had been estimated that 24 horsepower 

 was needed, provision was made in the contract that a duplicate 

 engine should be constructed immediately after the completion of the 

 first one. 



The ancestor of this engine was a four-stroke-cycle, air-cooled 

 three-cylinder rotary which Balzer had built for his 1894 automobile. 

 The automobile with its engine is on display in the Smithsonian 

 Institution, having been given by the builder on May 16, 1899. An 

 extra engine was delivered to Charles M. Manly of the Smithsonian 

 Institution on September 5, 1899. 



Wlien the end of February 1899 arrived, it was found that although 

 the engine builder had succeeded in constructing an engine which 

 weighed 100 pounds, and which theoretically should have given some- 

 thing over 12 horsepower, it was impossible to make it work properly. 

 The mechanical construction of the more important parts had been 

 well executed, and this main portion of the contractural work was 

 completed within the time called for by the contract. The trouble 

 was that the engine, which was of the rotary-cylinder type, would not 

 furnish anything like the power which had been expected of it, and 

 which the size and number of its cylinders indicated that it should 

 furnish. 



At this point Charles Manly took command of the situation. He had 

 been appointed Langley's assistant in these experiments two years pre- 

 viously at the age of 22, having graduated with distinction from the 

 Cornell University School of Engineering. 



