86 W. & L. E. GURLEY, TROY, NEW YORK 



maintained by hardening the end of the escapement shaft 

 and using a sapphire bearing jewel. The escapement must be 

 so arranged that it may be thrown out of mesh with the clock 

 train to make it possible to set the clock to the proper time with- 

 out changing the relation between the time type wheel (5), the 

 clutch (11), and the hands. (See Fig. 45, page 92). 



THE COVER 



A tight fitting cover should enclose all automatic recording 

 registers so as to exclude dirt from the mechanism. Dust or 

 grit settling on the gears and bearings of any time piece soon 

 interferes with its satisfactory operation. 



TYPES OF GURLEY AUTOMATIC WATER 

 STAGE REGISTERS 



Gurley automatic water stage registers are divided into three 

 classes those making a printed record, those making a graphic 

 record, and those transmitting a record from a distance. In 

 the printing type a simultaneous record of water stage and ti UK- 

 IS made; in the graphic type the record is made continuously 

 by a curve, the coordinates of which are the time and the stage; 

 the long distance register records the time and the changes in 

 level on a chart situated some distance from the body of water 

 which is being gaged. All three classes of registers will be 

 described in detail. 



