U. S. NATIONAL MUSEUM 



BULLETIN 173 PLATE 16 



Adjustable Cut-off Valve Gears. 



1, SIckels drop cut-off valve gear, 1841 (model; U.S.N. M. no. 180973). See p. 62. 

 2. Allen cut-off valve gear, 1841 (model; U.S.N..M. no. 308649). See p. 62. 



