NCE 



[Eiiieri'd at tlie Posi-Offlce of New York, N.V., as Sfconfi-Class Matter.] 



A WEEKLY NEWSPAPER OF ALL THE ARTS AND SCIENCES. 



Sevknth Year. 

 Vol. XIV. No. 337. 



NEW YORK, July 19, iJ 



Single Copies, Ten Cents. 

 $3.50 Per Year, in Advance. 



THE SPRAGUE ELECTRIC-RAILWAY MOTOR. 



We publish in this issue views of the Sprague improved electric 

 motor for street-railway work. This motor represents the experi- 

 ence of several years in the electric street-railway business, and it 

 is intended to meet all the exigencies in this kind of work. In its 

 manufacture, every detail of mechanical and electrical construction 

 is carefully attended to, and the most recent improvements which 

 experience could suggest have been adopted to meet the necessities 

 of street-car service. 



Only one intermediate shaft is used between the armature pinion 

 and the main gear, and the entire reduction is about 12 to i. All 



The armatures are of the type which has been proved to be 

 water-proof, and incapable of injury by moisture. In a recent test 

 upon one of these armatures, made at the Sprague factory at 

 Schenectady, and described in this paper a short time ago, one of 

 these armatures was placed successively in a tub of fresh water 

 and allowed to remain there for twenty-four hours, and in a tub of 

 salt water and allowed to remain there for the same time. After 

 each of.these baths, the armature was placed in position in the 

 motor, and the machine was worked to one-third above its normal 

 load, as measured by a dynamometer, for several hours without 

 developing any trouble whatever. These tests proved most con- 

 clusively that these machines can be relied upon under all condi 



FIG. I. — NEW SPRAGUE ELECTRIC-RAILWAY MOTOR. 



the gears and every part of the motor are made extremely strong 

 and durable, as can be seen in the case of the gears in the engrav- 

 ing, where the general appearance of durability and strength is 

 everywhere marked. 



The main gears are of the split-gear pattern, so that in case of 

 necessity they can be easily removed from the shaft without dis- 

 mounting the machine. The pinion and all the bearings are also 

 constructed so that they can be easily removed if necessary. 



Great attention has been paid in this motor to obtain a machine 

 which will require a minimum amount of care, under the unfavor- 

 able conditions which motors for street-railway work very often 

 meet in actual practice. For this reason, all the bearings are made 

 completely dust-proof and very durable. 



tions of weather, and that they cannot be harmed by moisture or 

 by water splashing upon them from the road-bed. 



Another important improvement which has been adopted in this 

 machine is that the field-magnet coils are completely incased in 

 covers, as shown in the engravings, which fully protect the wire 

 from all outside damage. These casings are hermetically closed, 

 so that it is impossible for moisture to affect the coils in any way. 



The style of brushes used upon these motors is of a new type, 

 which has been shown to give excellent results in this kind of work. 



The Sprague method of flexibly suspending the motors, and of 

 controlling the speed of the motor without the use of any wasteful 

 resistances, is also in use with these motors upon all the roads in- 

 stalled by the Sprague Electric Railway and Motor Company. 



