370 



Popular Science Monthly 



A Low Water Alarm for Boilers, Which 

 Has No Stuffing Boxes 



WHISTLE 



Sg-in. 



When the Water in the BoiUr Falls 

 Below a Safe Level the Whistle Wii! Blow 



''T^HE low water alarm for steam boil- 



J. ers shown in the illustration has no 



packing boxes, the principal objection to 



home-made alarms. 



A whistle is connected with a 

 globe valve. From the valve a piece of 

 'js-'m- iron pipe leads down. Locknuts 

 hold the iron pipe and the 

 boiler shell together at the 

 top of the boiler. 



To one end of a ])iece 

 of rod 7/16-in. in diame- 

 ter and 4 ins. long, a 

 washer is attached and 

 lo the other end a ball 

 (globe) float. The^^-in. 

 pipe and the 7/16-in. rod 

 are held together by a 

 ^S-in. check valve, which 

 is turned upside down 

 and the movable intericir 

 disk is then remo\c(l. 

 A pin is passed through 

 the rod within the valve. 

 This pin can be easily 



placed, as all upright checks unscrew to 

 permit access to the inside. 



Perhaps it would be a safer plan to 

 omit attaching the globe valve as it 

 might be closed accidentally or deliber- 

 ately, by a careless attendant. When 

 the water falls below a safe level the 

 whistle will blow. — James E. Noble. 



A' 



Locomotive Runs Three Hours 

 on Charge from Boiler Plant 



FI RELESS steam locomotive is used 

 for switching cars and tie trams at 

 an Ohio manufacturing plant. The 

 locomotive is of a t\'pe which was 

 developed in Europe some years ago and 

 is used around distillation plants, where 

 cinders and live ashes would constitute 

 a fire danger. It is operated by steam, 

 the boiler being charged about seven 

 times every twenty-four hours at the 

 main boiler, at one hundred and fifty 

 poimds pressure. The maintenance cost 

 is \ery low. The tractive power is fully 

 equal to that of the usual type, and 

 .ilthough it weighs only twenty-two tons 

 it has pulled as many as twelve loaded 

 gondola cars at a time. 



This "Grease Ball" Was a 

 Sticky, Insoluble Feed Water 

 Deposit Formed in a Boiler 



A "Soap" Which Is Not Used 

 for Cleansing 



F(^RTY miles removed from the 

 familiar grease product marketed as 

 different varieties of soap is the "grease- 

 ball" shown in the accompanying illus- 

 tration. It was formed in a boiler as a 

 deposit resulting from the precipitation 

 of the carbonates of lime and 

 magnesia in the feed water. 

 When feed water enters a 

 hot boiler the carbonates 

 of lime and magnesia 

 that the feed contains 

 arc precipitated from so- 

 lution and if the circula- 

 tion in the boiler is not 

 too active the precipita- 

 ted matter often floats 

 on or nc;u- the surface for 

 a lime in light particles. 

 When the floating car- 

 lioiiaU's imite with the 

 organic parts of any oil 

 tiiat may be in the boiler 

 the soap is formed. 



