562 KANSAS CITY REVIEW OF SCIENCE. 



dependent wire running below the ground from an instrument buried under the 

 track, to a telegraph pole where it is held aloft from all disturbing influences. 

 At night red lights are displayed. No weight less than five tons can open or 

 close the circuit. In this way the danger of collision is avoided and Hkewise the 

 overtaking of a slow train by a fast one, particularly at night on curves. To 

 show how quickly the value of a thing will appreciate if solid people can only be 

 induced to use it, this invention could have been had a couple of years ago for a 

 mere song. After a while the Pennsylvania Railroad was induced to try it on 

 their Tyrone division, the worst railroad division in the United States. Not an 

 accident occurred while it was in use. Then the road ordered it put on the 

 entire line from New York to Philadelphia, Pittsburg and Chicago, and on all 

 connecting lines, and to-day the patent that could have been bought two years 

 ago for a trifle could not be had for $1,000,000. — N. Y. Cor. Buffalo Express. 



A LOCOMOTIVE WITHOUT A SMOKE-STACK. 



Mallett's device for consuming smoke is about to be tested on the Erie rail- 

 way, on which a consolidated locomotive is being equipped. The smoke-stack 

 disappears entirely, and in its place is a man-hole merely. The gases produced 

 by the complete combustion will escape about the periphery of the extended boiler 

 casing. The fan is worked by a small engine in the smoke Dox, and a powerful 

 draft is maintained when the locomotive is at rest. The exhaust steam passes 

 along the side of the locomotive to the tender, which is divided into three com- 

 partments. The upper one is for fresh water, the middle one contains copper 

 tubes connecting with the external air in front and with a suction fan in the rear. 

 The exhaust steam circulates around the copper tubes and becomes in part con- 

 densed, the resulting hot water falling into the lower compartments. The uncon- 

 densed steam that comes in contact with a spray of water falling from the upper 

 compartment and the condensed water enters the lowest compartment, whence 

 hot water is pumped into the boiler. The air used to condense the steam is em- 

 ployed for heating and ventilating cars, being delivered through a conduit which, 

 with coupling ends, passes along beneath the cars. This system does away with 

 coal stoves or heaters, and supplies the cars with fresh air and warm air without 

 danger of fire in case of a smash up. When the locomotive now under way is 

 completed, it is proposed to make with it a transcontinental trial trip. — Railway 

 Ace. 



