602 



Popular Science Monthly 



A Self-Contained Hot Water 

 Foot Warmer 



JT has been shown that a certain com- 

 bination of salts brings about che 

 generation of heat. By applying this 



the ceiling to the opposite corner of the 

 room. This will take the cold air from the 

 floor and force it out at the ceiling level. 

 Naturally the air currents are forced from 

 a lower to a higher level, thus equalizing 

 the temperature. — John T. Ford. 



Pouring the salts into water to make a 

 mixture that produces and holds heat 



chemical phenomenon, a cheap and effi- 

 cient warming bottle may be formed. First 

 of all mix together sodium acetate and 

 sodium hyposulphate in water, using one 

 part of the former to nine parts of the lat- 

 ter salt. There should be a sufficient quan- 

 tity of these materials to fill the earthen- 

 ware bottle three parts full. The vessel 

 should now be loosely stoppered and 

 placed either in hot water or in an oven 

 until the salts have completely dissolved. 

 For many hours after this the bottle will 

 radiate considerable heat. To renew the 

 warmth-giving properties, it is only 

 necessary to give the bottle a good 

 shaking. — S. Leonard Bastin. 



Circulating Air in a Room to Warm 

 It Evenly 



THE temperature of a heated room is 

 several degrees warmer at the ceiling 

 than at the floor. To equalize the tem= 

 perature, it is necessary for the air to be 

 in circulation. This may be accom- 

 plished with an electric fan, but to pre- 

 vent any unnecessary draughts, the blast 

 from a fan should be confined. As the 

 air must be driven from the floor to the 

 ceiling, place the fan in one corner of the 

 room in such a position that it will drive 

 the air upwards. To keep the air con- 

 fined, make a cardboard tube about fi in. 

 in diameter to carry the air up and across 



Inward Flaring Cover for an Oil 

 and Plumbago Can 



THE photograph and drawings illus- 

 trate a very handy "dope" can 

 which is convenient in many ways to 

 the mechanic. The mixture, more com- 

 monly known as "dope," being a com- 

 bination of plum- 

 bago and oils, is 

 used on thread 

 joints to prevent 

 them from rust- 

 ing and being 

 difficult to re- 

 move. 



Due to the con- 

 struction of the 

 cap or cover, the can, if overturned or 

 upset, will ahvays retain a goodly portion 

 of its contents. Around the opening or 

 mouth a piece of wire is bent and soldered 

 in the form of a loop. This affords a good 

 swipe for the brush, cleaning ofT any 

 surplus which may adhere to the bristles. 

 It keeps the'mouth of the can clean as the 

 oil surplus drops at once into the middle 

 of the opening. The square shouldered 



You can't spill every- 

 thing from this can 



Details of the parts for making the can 

 with its flaring cover to hold the lubricant 



portion on one side will be found very 

 convenient for catching and holding the 

 can on any projection which may be near 

 the work requiring the application of the 

 dope.— F. W. Bentley, Jr. 



