INDUSTRIAL PROGRESS DURING THE YEAR 1876. ccv 



Railroad during the progress of the Exhibition, when millions of 

 passengers were carried over the road. This system is in operation 

 on the New York division, and on the main line between Philadel- 

 phia and Pittsburgh. It consists, briefly described, in dividing a line 

 of railway into sections or blocks, of such length that the movements 

 of trains thereon can be easily controlled by telegraph operators 

 stationed in signal-towers at the end of each block, who observe and 

 record the movements of trains by telegraph, and who operate the 

 signals by which the engine-drivers are directed. The apparatus of 

 each station comprises a signal-box (rising about eighteen feet from 

 the ground, and having sliding green and red signals, two on each 

 side, of different colors), located near the track, so as to be easily 

 seen by engineers of trains approaching from either direction, and 

 the telegraphic apparatus within. By means of strong cords con- 

 necting the signals of each side with the working-room of Ihe tower, 

 the operator within can conveniently make the necessary changes in 

 the signals. 



The operation of the system is described as follows : Red is the 

 stationary signal, and informs the engineer of an approaching train 

 that he can not pass until a second signal shows that the block is 

 clear. This information is conveyed by showing the white signal. 

 A green signal is understood to mean that the engineer can proceed, 

 but with caution, the block not being entirely clear of trains. The 

 exact time at which each train reaches a station is telegraphed at 

 once to the operators at the station just passed and the one next 

 succeeding. The operator is thus enabled to notify the engineer 

 of every train approaching a signal-tower with certainty of the con- 

 dition of the track between the given i3oint and the station next 

 succeeding. The order conveyed by the danger signal is impera- 

 tive, and no engineer dares to disobey it. Furthermore, no passen- 

 ger train is allowed to pass a station while another train of the same 

 class is on the block, or between the two stations, without a special 

 order from the superintendent. Freight trains are allowed to run 

 on a block in quick succession from two to five minutes behind each 



other. 



TECHNOLOGY. 



Mr. John E. "Wootten described at one of the late meetings of the 

 American Philosophical Society a combination of apparatus by 

 which ordinary anthracite coal-waste, from the dirt-banks at the 

 mines, can be profitably burned in the furnaces of stationary and 

 locomotive boilers. The essential features of this device are described 

 to be as follows : A closed ash-pan is provided, into which air is 

 injected by means of a steam-jet passing through one or more tubes. 

 Where volume of air rather than intensity is demanded, these tubes 

 should be cylindrical ; but when greater intensity is needed, as in 

 the case of locomotives, they should be formed of two frusta of 



