CATALOG OF THE MECHANICAL COLLECTIONS 57 



REILY AND WALDO ROTARY ENGINE, 1875 



U.S.N.M. no. 309192 ; original patent model ; transferred from the United States 

 Patent Office ; not illustrated. 



This model was submitted with the application for the patent, issued 

 to Henry Eeily and P. G. Waldo, of Pennsylvania, September 28, 



1875, no. 168184. 



The engine represented by the model is one of the large class of 

 rotary steam engines in which a rotating drum forms an annular 

 chamber with a larger cylindrical housing, within which a driving- 

 head bolted to the drum is forced around the annular space by the 

 expansion of steam between the movable driving head and a sta- 

 tionary abutment projecting into the annular space. The engine is 

 provided with two stationary abutments so that two expansions may 

 be obtained in one revolution of the driving head. The method of 

 controlling the admission of steam and the device for withdrawing 

 the stationary abutments to permit the passage of the driving head 

 are the peculiar features of this particular engine. 



SCHOFIELD ROTARY ENGINE, 1876 



U.S.N.M. no. 309193; original patent model; transferred from the United States 

 Patent Office ; not illustrated. 



This model was submitted with the application for the patent 

 issued to Frederick F. Schofield, of Oscoda, Mich., September 19, 



1876, no. 182291. 



This is a rotary engine in which the outer casing rotates and acts 

 as both flywheel and belt pulley. Otherwise it does not differ mate- 

 rially from the many other rotary engines in which an annular space 

 between a casing and a drum is divided by movable abutments in the 

 outer casing, and is traversed by a driving head on the drum. In 

 this case the drum is held stationary and the abutments in the casing 

 are driven around by the pressure between the abutments and the 

 head on the drum. 



THREE-STAGE STEAM TURBINE, 1926-1930 

 Plate 15 



U.S.N.M. no. 309881 ; original ; gift of the General Electric Co. ; photograph 

 no. 39036A. 



This is a modern steam turbine of the General Electric-Curtis 

 type, designed for auxiliary drives and small powers requiring 50 to 

 100 horsepower, at 500 to 7,600 revolutions per minute, using steam 

 at pressures of 100 to 400 pounds per square inch. The turbine is 

 cut away to show the details of construction and operation. 



49970—39 5 



