U. S. NATIONAL MUSEUM 



BULLETIN 173 PLATE 17 



Adjustable cut-off valve Gears. 



1. Francis B. Stevens cut-off, 1861 (model; U.S.N.M. no. 308644). See p. 66. 

 2. Corliss drop cut-off valve gear, 1849 (model; U.S.N.M. no. 308646). See p. 71, 



