For Practical 

 _ Workers 



A Foot-Warmer Attachment 

 for a Radiator 



THE fact that air currents pass up 

 through the sections of a steam or 

 hot water radiator so that the heat rises 

 before dispersing throughout the room 

 accounts for the floor under the radiator 

 being a poor place to warm the feet. 

 The shelf arrangement shown in the illus- 

 tration will be found very convenient for 

 supporting the feet at a comfortable 

 height near the side of the radiator 

 close to the heat. 

 The device i s 

 made of a board 

 15 in. long and 6 

 in. wide, with two 

 rods attached, ha\- 

 ing their upper 

 ends bent into 

 long hooks to en- 

 gage the connec- 

 tions between the 

 sections of the ra- 

 diator at the top. 

 This makes it easy 

 to remove the at- 

 tachment when not required. It may also 

 be used as a shelf on which to set articles 

 to keep them warm. — A. E. Hol.^dav. 



A shelf supported by long hooks attached 

 to radiator connections for a foot-warmer 



How Electricity and Temperature 

 Affect a Watch 



EVERY second counts — it counts 

 half a revolution of the balance 

 wheel of your watch, 1,800 revolutions 

 an hour; so, an\thing that will affect 

 that i2-in. coiled spring that go\erns the 

 escapement may make you miss your 

 train — or make your train miss its 

 signals and safety. 



The effects of varying temperatures 

 have been compensated for even in 

 watches that need not be \-ery accurate, 



and especially in carefully designed time- 

 pieces. The effects of magnetism are 

 also considered, the influence of which 

 has been minimized in the last few years 

 because of the development of electric 

 generators. But watches still are liable to 

 impairment from electrical influence, 

 even in the slight amount of static 

 electricity created by the friction of 

 steel wheels on steel rails when a train 

 or car starts or stops suddenly. 



A simple experiment, showing how 

 a watch may be 

 magnetized with- 

 out actual contact 

 with the magnet- 

 izing source, may 

 be conduc ted 

 with paper, 

 some steel filings 

 and an ordinary 

 magnet. The mag- 

 netic field will be 

 indicated by the 

 lines of force in 

 which the steel fil- 

 ings will arrange 

 themselves when the magnet is held 

 under the paper. With a magnetizing 

 source more powerful and its extent of 

 influence proportionately greater, it may 

 be readily seen how the steel in the 

 watch may be magnetized — the steel 

 parts, of course, retaining the magnet- 

 ism, which, as the parts of the watch 

 assume various relative positions in 

 moving, causes them to be affected so 

 that they are retarded or accelerated. 

 Whereas a watch in perfect working 

 condition may be adjusted to vary only 

 an average of .23 seconds daily, a 

 magnetized watch will var\' from i to 

 125 seconds an hour. Of course a 

 watch may be demagnetized, but it 



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