246 COALFIELDS AND COLLIERIES OF AUSTRALIA. 



the Sullivan electric chain machine, the Jeffrey chain breast 

 machine, the Jeffrey short wall coal cutter, and the Goodman 

 chain-breast machine. 



The Sullivan, Fig. 154, is heavier, and requires more 

 power than the other machines. First of all the main pan is 

 jacked against the roof to prevent it from working back- 

 wards ; the machine is then worked forward oft' the main pan, 

 at the same time putting in the sumping cut. When the 

 machine is completely on the front pan, the two pans are dis- 

 connected, and the main pan drawn out of the way. This 

 enables the machine to work in less space than ordinary chain 

 breast machines, and therefore it does not interfere to the 

 same extent with the props. The chain along which the 

 machine pulls itself is anchored at the far side of the bord and 

 jacked at the other. The anchor consists of a short piece of 

 plate iron bent in such a way that one end digs into the pillar 

 while the other end digs into the floor. A hook is connected 

 to the plate, and to this the chain is fastened. Being out of 

 the way, it does not interfere with the machine cutting close 

 up to the pillar. When the machine has made the sumping 

 cut 6ft. deep, it then cuts sideways for the width of the bord, 

 sliding on a rail placed near its forward end. This leaves the 

 back clear for a man to shovel the cuttings brought out by 

 the picks. When a cut has been completed, the machine is 

 placed on a trolly and drawn by a horse to another bord. Each 

 machine requires three men: one to drive it, another to shovel 

 away the cuttings, and the third to shift the rails, lubricate 

 and generally to assist. The trailer cable is clipped to the 

 main cable, the bare wires at the junction being covered by a 

 rubber sleeve. 



The old type of Jeffrey machine, as also the Goodman 

 chain breast machine, work intermittently. As each cut is 

 only 2ft. 9in. wide, when the full depth of the cut has been 

 made, the machine has to be withdrawn and moved sideways 

 for a fresh cut. The new type of Jeffrey machine (Fig. 155) 

 works right across like the Sullivan, but instead of a chain two 

 flexible galvanised iron ropes are threaded through the 

 machine and anchored at either side of the bord; one is to pull 

 on, the other to keep the machine straight on its course. This 

 machine makes a cut 6ft. deep, and is found to do excellent 

 work. When flitting from one place' to another, it is mounted 

 on a self-propelling trolly. All the coal cutters are 

 driven by electricity. It is found advisable to have a large 

 number of coal cutting machines, even if they are not all in 

 use at once, for though when at work a machine may cut 20in. 

 per minute, it takes so long to shift the machines about that 

 the average is reduced to about 5in. per minute. It is found 

 when working machines on the tonnage rate that the men 



