572 



A Danger Signal Which Compels 

 Attention 



ONCE upon a tinu- it was 

 possible to stand on the 

 corner of a reputed dangerous 

 thoroughfare in a large city or 

 e\'en in the large towns and 

 especially at railroad cross- 

 ings and experience many 

 of the thrills of melodrama 

 at the narrow escapes of 

 pedestrians and vehicles 

 from accidents. But to-day 

 so many precautions are 

 taken and danger signals 

 arc so ninniTous and so 

 cleverly planned that the 

 number of accidents is mini- 

 mized. 



An electric signal has 

 been designed for a danger- 

 ous corner where obstruc- 

 tions, such as trees and 

 buildings close to the side- 

 walk or fences, shut off the 

 view of approaching street- 

 cars on a cross street from 

 vehicles on the main street 

 until it is almost too late to i)re\'ent 

 serious accident. 



The cross-piece on top of the signal - 

 post is connected by wire with a magnet 

 over which the wheels of the car pass as 

 it nears the corner. This contact of the 

 wheels with the magnet sets the cross- 

 I)iece in motion, and it continues to 

 oscillate, (lasiiing its brilliaiU colors 

 insistently, until the car wheels have 

 come in contact with a lever on the 

 other side of the danger zone, the press- 

 ure upon which has released the signal 

 wire. This serves as a reminder to tlir 

 motorman to slow up as he nears the 

 corner and as a warning to ]x>destrians 

 and drix'crs of vehicles that a car is 

 approaching. 



At night the word D.'XNGKR shines 

 out in ihuminated red letters, the lights 

 being enclosed in the bo.\ on which the 

 lettering apjjears. A space is also re- 

 served for the name of the crossing 

 streets, making the sigiial-i)()st a sign- 

 post as well. The colors I'mployed are 

 eye-conipc-lling, and the de\'ice has 

 [)roved to be an eflicii'nl guardian of the 

 public safety at that |)arliiiil.ir coiiur 

 which has no traflic policeman. 



Popular Science Monthli/ 



Thi- hi illi.iiit colors and 

 the revolving cross-piece 

 cannot fail to attract 



1 



A Safety- Bicycle for the Timid 

 '4 Fat Man 



THE fat man who wants to 

 reduce by bicycling but 

 ho does not want to fall oflf 

 and injure himself in the at- 

 tempt, can now ride with 

 safety on a bicycle fitted 

 with a new rear attachment 

 which will prevent him 

 from losing his balance. 



The frame of the bicycle 

 carries an extra pair of 

 small wheels at the back 

 alongside the rear wheel. 

 When these are attached it 

 is no effort to maintain 

 one's balance. Moreover 

 the- new attachment makes 

 it easier to mount and 

 dismount. 



The wheels are so small 

 that they are scarcely 

 noticeable to the casual 

 observer. Besides the feel- 

 ing of security which their 

 perfect balance gi\es, they 

 also share the weight. 



How could any one 

 fall ofT if his wheel is 

 constantly propped up? 



