MINING. 125 
swung around and the mine car body let down by means of 
the same screw either on to. the room tram or on the “slope 
tram.” 
In this method the engineman alone takes the place of all 
the trammers who, in other methods, are employed in bring- 
ing coal from the rooms or “breasts.” In this method of 
mining the “medium dip” coal, there is a less amount of 
narrow work in the form of gangways and air courses, than 
in any of the usual methods; there is a much lighter force 
of trammers needed, and especially there no coal rakers, 
killing time in the shutes, in their dallying efforts to get the 
coal down the shutes to the gangway, 
If the Pit Head Frame and loading shute and screws are 
properly arranged, the “medium dip” coal can be mined by 
this method at a very little if at all higher cost than the 
coal of the flatseams. The preceding diagram shows a sec- 
tion along the hoisting slope, giving an outline of the “slope 
tram,” with form of the platforms or scaffolds for holding 
the mine car bodies; also a ground plan of the hoisting 
slope with its connecting room roads, and sidings for empty 
mine cars; also the position of the iron post cranes for re- 
ceiving and delivering the mine cars. 
The first duty of the miner on arriving at the slope from 
his room with his full mine car, is to signal to the engine- 
man by means of the annunciator, that his number requires 
the “tram slope” with empty car, and is ready to deliver a 
full car; the engineman’s duty, after acknowledging receipt 
of this order, is to signal back to the number at which he 
intends to stop his “slope tram,” that he is going to stop 
at that point. As the slope tram nears this place the en- 
gineman causes it to move slowly in order to give the miner 
the opportunity of seeing which platform of the tram holds 
an empty car body, and of stopping it, by throwing up his 
catch lever, so as to bring this platform and empty car body 
exactly opposite his room track. He then removes the 
empty, and puts on the full car body and signals to the en- 
gineman to hoist away. He then swings the empty car 
around upon the room tram, pushes it back to the breast to 
be loaded again. The signals between the miner and the 
engineman must be the “electric,” each miner having a wire 
