536 



Popular Science Monthly 



A track surfacing and tamping gang on the New York Central. Tiie compressor car is 

 mounted beside the track to furnish compressed air to the tampers 



Tamping Railroad Ballast with a 

 New Air-Tool 



A GOOD roadbed is one of the 

 greatest assets of a railroad. There 

 is almost as much difference between 

 riding over a well and a poorly main- 

 tained roadbed as be- 

 tween jitneying over 

 an asphalt and a cob- 

 ble pavement. 



Tamping the crushed- 

 stone ballast under- 

 neath the ties is partic- 

 ularly difficult. For- 

 merly tamping was 

 done by hand with the 

 aid of a pick or a long 

 bar with a blunt end. 

 Now, many of the pro- 

 gressive railroads use 

 a novel type of pneu- 

 matic tamper. In tun- 

 nels and terminals, 

 where compressed air 

 is employed for operating electro-pneu- 

 matic signals, it is simple to connect the 

 tools with the compressed-air pipe line by 

 means of a hose. For work out on the 

 road, where a supply of compressed air 

 is not available, air is supplied by a small 

 engine-driven compressor, mounted on a 

 special car. The gasoline-engine also 

 drives the car. 



An interesting feature of this car is 

 the method of quickly derailing it and 

 placing it beside the tracks. Four small 

 wheels are set at right angles to the 

 main wheels. By placing a few lengths 



The men generally work in pairs 

 on opposite sides of the ties 



of timbers under these wheels, the car 

 can be run oft" the track in a few seconds. 

 Electric railroads employ a similar type 

 of compressor-car, with an electric mo- 

 tor instead of a gasoline engine to run 

 the compressor. 



The pneumatic tamp- 

 ing inachine works on 

 much the same princi- 

 ple as the familiar 

 pneumatic riveter. A 

 piston or hammer de- 

 livers eight hundred 

 sharp blows per minute 

 on the end of a tamp- 

 ing bar, which is in- 

 serted in the nozzle in 

 the lower end of the 

 tool and which is 

 locked in position. The 

 bar cannot be knocked 

 out, yet the operator 

 can shift it from one 

 position to another. 

 The tampers are usually worked in 

 pairs on opposite sides of the tie. The 

 face of the tamping bar presses against 

 ballast beneath the bar under and to the 

 center of the tie. This actually lifts the 

 tie and track as much as may be desired, 

 and packs the ballast tight. The blows 

 are light ; consequently the ballast is not 

 broken as much as with hand tamping 

 and less damage is done to the ties. 



The New York Central found that its 

 savings by changing from hand tamp- 

 ing to pneumatic tamping amounted to 

 over $150 per mile of track. 



