18 TRANSACTIONS OF THE NOV. 3, 



The " Low Point Markers '' are carried bj- auxiliary inflexible 

 bars, connected directly to the journal boxes of the outer wheels ; 

 the intermediate wheel carrying the striker. The " markers " 

 are operated by compressed air — of 60 to 75 pounds pressure — 

 from the air-brake reservoir. Resting upon the bars is a cylin- 

 der with piston, the rod extending below, and forming the 

 plunger of the pump which ejects the paint ; the pressure on 

 the fluid is from 150 to 200 pounds per square inch. Each 

 "Low Point Marker" has a slide valve raised by springs, so 

 that when tlie striker is off the valve-stem, the air and fluid pis- 

 ton is raised ; when the intermediate wheel, which carries the 

 striker, goes into a depression below what the instrument is set 

 to mark — flve-sixteenths of an inch, or less, — the valve is de- 

 pressed, cutting off and releasing the air from the under side 

 of the piston, admitting the air above, forcing down the piston, 

 and ejecting the paint under the head of the rail where there 

 are deflections for want of proper tamping, deflections over rot- 

 ten or loose ties, bad bends in the rails, weak or worn-out joints, 

 etc. The color will last from fom* to six weeks, showing to 

 trackmen where their laboi" is needed. 



Deflections in the rails under the trains occur of more or 

 less extent, and a permanent set takes place, of some of the 

 forms shown in the cuts. The trackmen do not see these de- 

 flections when they first occur, and it is not until the rail has 

 acquired some permanent set that they give them attention. 



Roads have been brought to a much better condition of track 

 by the car passing over periodically, and having the surfacing 

 done according to the indications of the " Low Point Markers," 

 — directing the tabor to the points where it was needed, and 

 saving 7nuch which is unnecessary. 



The business on our trunk-lines is now so great that a slight 

 difference in condition of track increases the operating expenses 

 in a far greater ratio than most railway men l)elieve. 



The dominant Form in which rails are found in a track is a 

 reliable indication as to the cost of freight-car repairs and the 

 cost of transportation. A road in 1881, with rails of the 3d 

 and 2d Forms, doing a business of 2,688,112,481 ton miles : 

 the cost of freight-car repairs per ton mile was $0.00 0335. 



Another road, same year, rails of 1st Form, doing a business 

 of 2,705,165,840 ton miles: the cost of car repairs per ton mile 



