Popular Science Monthly 



not slide while the vehicle is in motion. 

 Its center of gravity is well forward of the 

 Ford rear axle in order that its weight 

 may be partly distributed over the front 

 wheels. 



To load the piano onto the platform 

 easily, two stout plank skids are provided. 

 These have angle-iron hooks 

 on their forward ends, which 

 slip into staples bolted to the 

 rear of the platform, 

 the piano has been 

 loaded, the skids 

 are removed from 

 the staples and 

 pushed forward un- 

 der the platform, 

 so that their over- -< 

 hanging ends do 

 not present a men- 

 ace to pedestrians. 



In this way the 

 piano is as safely 

 moved as in a fully 

 equipped van. 



After^ 



)--," 



This electric attachment makes one 

 blanket sufficient for the coldest night 



Lo! The Electric Blanket. It Always 

 Keeps You Just Warm Enough 



SLEEPING out-of-doors has been 

 robbed of its most unpleasant feature 

 - the chill. No 

 longer is it neces- 

 sary to shiver with 

 cold, or to pile un- 

 comfortably heavy 

 bedclothes over 

 yourself. 



An electrician 

 has devised a light 

 blanket which is 

 electrically heated. 

 The blanket is 

 equipped with three 

 heats, so that you 

 can have it mildly 

 warm, warm, or al- 

 most hot, with the 

 expenditure of but 

 a small amount of 

 current. 



No Passing Traffic Can Interfere 

 With This Policeman's View 



AP E R M A- 

 NENT nest 

 of wood and iron 

 construction, 

 standingmorethan 

 fifteen feet high, at 

 the intersection of 

 six streets in the 

 busiest part of De- 

 troit; will be Used 

 by a policeman, to 

 direct traffic going 

 in twelve direc- 

 tions. In this nest 

 the officer is high 

 enough to see sev- 

 eral squares each 

 way, which enables 

 him to avoid con- 

 fusion and acci- 

 dents! The station, 

 w^hich is glass en- 

 closed and heated, 

 has a signal equip- 

 ment, so that it 

 can easily commu- 

 nicate with nearby 

 busy traffic posts. 



An elevated policeman's nest, with the 

 direction indicators in clear view of all 



What Causes the Singing of 

 Telegraph Wires? 



THE singing of 

 telegraph 

 wires is sometimes 

 regarded as a 

 weather prognos- 

 tic, though opin- 

 ions differ as to the 

 kind of weather it 

 foretells. , There 

 has been much dis- 

 cussion as to the 

 cause of this sound. 

 Probably it is sim- 

 ply the Aeolian 

 harp effect, and its 

 occurrence de- 

 pends chiefly upon 

 the direction of 

 the wind in rela- 

 tion to the direc- 

 tion in which the 

 wires run. Varia- 

 tions in thepitch of 

 the sound depend 

 upon changes in 

 the tension of the 

 wires with varying 

 temperature. 



