258 Machwe/or securing Depredators. 



perspective view of this machine. Fig. 1. ABC is a frame 

 of wrdught iron, about 18 inches square; it has an eye pro-' 

 jecting from it to receive a short chain, the other end of 

 which is fastened to an iron screw, shown separately at D, 

 screwed into the earth bv the key or handle E: this screw 

 is about 14 inches long, and, when screwed into hard- 

 ground, will hold so firmly, that there is no danger of its 

 being drawn out, even by two or three men ; and having a 

 small square end, it cannot be turned without the key or 

 handle E y so that an offender would find it extremely diffi- 

 cult to remove the trap: eefg are two iron frames moving 

 on centres in the frame ABC ; these frames have a constant 

 tendency to close together, by means of two springs pp, 

 fixed in the frame AB, and acting against pins projecting 

 from the upright sides of the moveable frame ee ; k k are 

 two small iron rods jointed to the upper rod of the moveable 

 frame g, and passing through small locks / /, fixed to the 

 other frame/'. These locks contain clicks which are pressed 

 by springs into the teeth, as may be seen upon the rods k k f 

 so as to prevent the two bars J'g from being drawn asunder 

 when they have been closed by means of the springs pp. 

 The internal mechanism of the locks is explained by figures 

 2, 3, on a larger scale at LM, in the same plate; one side 

 of the lock is supposed to be removed to exhibit its interior 

 parts, where k represents the rack, or that part of the rod 

 •which is cut into teeth, r is the click, which engages the 

 reeth of the rack, and prevents its being drawn through the 

 lock : the click is pressed against the teeth of the rack by 

 a spring, which is plainly seen in the figures; the locks are 

 attached to the ends of the bar/' of the moveable frame, by 

 the bar passing through the locks, and when the lids are 

 riveted on it is confined m such a manner that it cannot 

 be got out. But as it is necessary to open the bars fg, and 

 draw the clicks back from the teeth of the racks, Mr. Sal- 

 mon has contrived two different methods of accomplishing 

 this object. Figure 3. M is that which is used ill the mo- 

 del left at the Society's Repository ; a small key or screw S- 

 is put down through a hole in the lid of the lock, and iy 

 received into a hole lapped with a screw in the click : bv 

 turning the screw it lifts the click out of the teeth of the 

 rack ; so that the moving frames jfg can he opened apart 

 from each other, till they lie fiat upon the frame AB. The' 

 iron cross m is then put between the two rods j'g, the screws 

 S of the two locks are to be withdrawn from the locks, and 

 the trap is set for use. If an offender should place his foot 

 within the square of the frame, he would tread down the 



crosi' 



