226 



CENTRAL SCIENTIFIC CO., CHICAGO, TT. 8. A. 



No. F3865A. No. F3867. 



4994. RHEOSTATS, Plate Type, tapered (i. e., having the first step of greater current-carrying capa- 

 city than the others). Of rugged construction, intended for permanent mounting upon wall 

 or switchboard, for use in field regulation of motors or dynamos. They will find many other 

 uses in the laboratory where a permanent rugged rheostat is needed, such as the control of cur- 

 rent for electric combustion and muffle furnaces, control of direct current for electrolytic 



A B 



1 2 



0.5 1 



150 75 



26 26 



1 1 



8 8 



Each ................................ $6.50 6.50 



work, etc. No 



Maximum amperes, first step .......... 



Ampere capacity, with entire rheostat in 

 circuit ............................. 



Total resistance, ohms ................. 



No. of steps .......................... 



No. of plates in parallel ............... 



Diameter of plates, inches 



5002. ROTARY CONVERTERS, for changing direct to alternating current. 



No. 



A 



110 



160 



70 



125 



47.00 



and regulating rheostat. 



D. C. volts 



D. C. watts, approx. 

 A. C. volts, approx. . 

 A. C. watts, approx. 



Each 



F3865. TRANSFORMERS, Laboratory. For use on 110 Volt A. C. Circuits to give alternating currents 

 at from 2 to 28 volts, which will operate all classes of small electric apparatus (A. C. or D. C.), 

 including induction coils, motors and small lamps. 



These transformers are indestructible, being enclosed in a steel shell, and operate on 100 to 125 

 volts, 60 cycles. The windings are embedded in an insulating compound making them imper- 

 vious to moisture and cementing the entire winding into one solid block. 



They are equipped with a new voltage regulator, which eliminates the necessity of a rheostat 

 for controlling the secondary voltages and permits of the voltage being varied in steps of two 

 volts. Voltages 4, 6, 8, 10, 14 and 18 are obtained by connecting to binding posts on the 

 transformer without the use of the voltage regulator and any of these six different voltages 

 can be used simultaneously. 



Each transformer is furnished with plug and flexible attachment cord for connecting trans- 

 former to line circuit, as well as secondary terminals on the secondary side, and bears a name 

 plate giving complete enumeration of the various voltages obtainable from it. 



No .". . A B C 



Capacity, watts 75 100 150 



Dimensions, inches 4Vix3%x3i4 5x4x3% 5%x5x4 



Weight, Ibe 5 8 11 



Each 4.00 5.50 7.50 



