62 Popular Science Monthly 



A Drawbridge Gate Which Will 

 Stop Any Automobile 



still further absorbed as the spring is further 

 compressed. Before the car has gone a half 

 dozen feet forward, all of its "push" will 

 have been completely destroyed without 

 producing any undue strains on the gate. 

 The method could be relied upon to stop 

 anything short of a railroad train! 



A runaway car striking 

 against this gate would 

 be stopped by the cush- 

 ioning of the huge gate- 

 springs in the cylinder 



DESPITE even the 

 massive iron gates 

 that swing across a road 

 when a drawbridge is 

 opened, automobiles 

 break through occa- 

 sionally and plunge 

 into the river below. 

 Such accidents occur 

 when the brakes jam. 

 Here was an op- 

 portunity for an in- 

 ventor. It was seized 

 by Jacob Harsen, a 

 highway engineer of 

 New York, who has 

 invented a cushion 

 lock for gates. Four 

 huge "locomotive" 

 springs are mounted 

 inside of four cylin- 

 ders at the ends of the 

 swinging gates on each side. 

 The cylinder plungers, which 

 work against these springs, 

 form one piece with the gate 

 coupling, which is locked by 

 the gateman when the draw- 

 bridge is about to be closed. 

 When the automobile strikes 

 the gate at high speed, the 

 huge springs are slightly com- 

 pressed ; then the gate "gives" 

 away gradually. The energy 

 of the automobile's impact is 



Gate locked in normal 

 position! 



Detail of the cushioning spring. The cylin- 

 der plungers which work against these springs 

 form one piece with the gate coupling 



The Wooden Hand Rammer — 

 A Survival of the Fittest 



URING the last five years 

 the electric chain rammer 

 has disappeared from the tur- 

 rets of modern warships. A 

 short circuit on one of the 

 battleships almost led to 

 disastrous consequences. 

 In other cases a tempora- 

 ry breakdown spoiled the 

 turret's chances in record 

 firing. Gradually the old 

 hand rammer, which 

 in principle has changed 

 little since Nelson's 

 men rammed the 

 round shot home in 

 the muzzle loaders, 

 has won back its 

 supremacy. The 

 turret of a Dread- 

 nought is filled with 

 other electrical de- 

 vices, but the 

 wooden rammer is 

 the one bit of equip- 

 ment that has sur- 

 vived from the days 

 of wooden ships, so 

 far as the turret is 

 concerned. 



Spring in all cylinders 

 pressed 



The electric chain rammer was placed directly in the 

 rear of and parallel to the bore of the turret gun 



