MILITARY ENGINES. 123 



small chest for implements and a few rounds of fixed ammunition, ball and 

 grape. Garrison carriages are not designed to be moved any great distance; 

 they can be, therefore, and for heavy calibres of garrison guns must be, very 

 much stronger and heavier. For the same reason they require either no 

 wheels at all or very small ones. The simplest garrison carriage is the 

 rampart-carriage of Gribeauval (/?/. 38, fig. 1). It consists of two strong 

 cheeks connected by the bolts q, d, k, and can be moved backwards and 

 forwards on the platform, on the block- wheels r s, by handspikes in the 

 rings and hooks, h, I. These carriages are so low that the piece on its 

 trunnions only just clears the sole of the embrasure. To fire " en bachette," 

 however (that is over the crest of the rampart, without embrasures, so that 

 the piece ranges freely in all directions over the superior slope), a higher 

 carriage is used, the travelling garrison-carriage of Gribeauval {pi. 37, fig. 

 11, is the side-view, fig. 12, the rear view, and fig. 13 is the carriage placed 

 upon the platform- wagon for transportation). A is the cheeks, made up of 

 the three blocks ah c, scarped together and connected by bolts and tran- 

 soms ; B, the elevating screw ; C, a support in which the block- wheel, D, 

 runs upon a separate beam, H, of the chassis I, its track sloping upwards as 

 it gives back, to diminish the recoil ; E is a bar for moving the piece back- 

 wards and forwards ; K, the fore wheels, with thick tires, G, and the axle Q. 

 For transportation, a long beam, L, with a pintle-hole, is inserted into the 

 carriage and put over the pintle-bolt, M, of the limber, 0, of the platform- 

 wagon, so that the wheels, P, make the fore wheels of the carriage. The 

 chassis upon which the carriage runs behind the embrasure consists of two 

 side-sills, two head-sills, and a middle-sill, H, for the truck-wheel, D ; it is 

 moved from one side to the other on the platform, as the direction requires. 

 Of similar construction is the French iron coast-carriage (fig. 16). Foi 

 this there lies, behind the breastwork, a small platform, A B, upon which in 

 rear is the curved piece C, for the truck-wheel, G, to traverse on, and in 

 front a broad sill, D, for the fore wheel, M. The traversing platform (chas- 

 sis), E, revolves around a bolt in the front part of the platform, A. This 

 traversing platform has a groove on each side in front, in which the cheeks 

 of the carriage proper can slide back for the recoil ; it is itself made to tra- 

 verse by means of the beam, F. The carriage consists of the uprights, H, 

 which are united to the bed, K, by means of the brace, I, and which sup- 

 port the trunnion beds. L is the elevating-screw. Another garrison-carriage 

 for use in casemates is the invention of Montalembert {fig. 14, side, fig. 15, 

 upper view). The chassis, A, is higher behind to check the recoil, and tra- 

 verses upon a circular platform by means of the truck-wheel, B, and upon 

 the sleeper, E, by means of the lever, I ; the low cheeks, D, run by means 

 of the truck-wheels, C, and a small wheel lying under the beam, G, back- 

 wards and forwards upon the chassis, A ; H is a transom near the wedge 

 of the elevating-screw. The truck-wheel, C, is shown mph S7, fig. 21, and 

 it is seen in what manner it is made up of six wedges, a, held together by 

 the tire, 6 ; at c is a racket- wheel, which is caught by a panel on the car- 

 riage, so that, after recoiling, the piece is kept stationary until it can be 

 loaded. For the service of the piece the rampart sponge and the rammer, 



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