52 BUUbETIN 127, UNITED STATES NATIONAL MUSEUM, 



as distinctly as I had done the engine and the propeller, which he 

 had seen in the hands of the workmen by whom it was manufactured. 

 The dates corresponded, and the apparatus was avowedly the mak- 

 ing of Stevens of Hoboken. Thus it happened that an accidental 

 choice had placed upon the committee two persons who were, by the 

 union of their testimony, capable of establishing the fact into the 

 truth of which they were directed to inquire." 



In the year 1844, by the direction of the sons of Colonel Stevens, 

 this twin-screw engine and its boiler were overhauled by Mr. Isaac 

 Dripps, then general superintendent of machinery on the Camden 

 & Amboy Railroad, and afterwards in the same position on the Penn- 

 sjdvania Railroad. The directions to Mr. Dripps were to make no 

 alterations or additions except in minor parts where worn. The 

 defects of the soldered pipes and joints were then remedied. The 

 parts added in 1844 are shown on the machinery, colored yellow. 



As the original boat had decayed in 1844, a new one was then built 

 to receive the engine; and the boat with the engine then in it was 

 exhibited at the fair held at Niblo's Garden, Broadway and Prince 

 Street, New York, in October, 1844, and tried on the Hudson River, 

 where it attained a velocity of 8 miles an hour. 



The twin-screw engine and its boiler are now in exactly the same 

 condition as when exhibited in 1844. They were preserved in the 

 Stevens Institute at Hoboken, N. J., until sent to the World's Colum- 

 bian Exposition, after which they were transferred to the Smith- 

 sonian Institution at Washington. 

 Deposited by Edwin A. Stevens. Cat. No. 181,179 U.S.N.M. 



THE STEVENS MULTITUBULAR BOILER. 



John Stevens patented his multitubular boiler in this country on 

 August 26, 1791, and August 11, 1803, and in England on May 31, 

 1805. In addition to the boiler exhibited, two more are described, 

 one having 81 tubes each 1 inch in diameter and the other having 

 about 765 horizontal tubes each 1 inch in diameter and 2 feet long, 

 placed between two tube sheets of cast brass, each sheet being 4 by 6 

 feet, the tubes being spaced 2 inches from center to center. The tube 

 surface was 400 square feet. Another form of this boiler, with ver- 

 tical iron tubes, that operated an experimental locomotive at Hoboken 

 in 1825, is still preserved in the National Museum. 



The English patent of 1805 was taken out by John Cox Stevens, 

 then a very young man, who described the subject of the patent, the 

 multitubular boiler, as " an invention communicated to him by his 

 father." It was he whom Doctor Renwick recognized as coxswain 

 of the " queer sort of a boat " at the Battery in May, 1804. In later 

 3^ears he was the founder and first commodore of the New York Yacht 

 Club, and commanded the yacht America in her famous race off the 



