IN TIME OF WAR. ' 241

The number of beds for each mortar is likewise increased,when the chambers are to be filled wish powder ; as theshocks are then very violent, and soon render them unser-viceable.

'1 he quantity of tools for the pioneers, and for makingfascines and gabions, are regulated by the works that areintended to be thrown up ; whether lines of circumvallation,or only approaches and batteries on the front of the attack.

The quantity of powder is computed from the numberof rounds (20), and the proportion for each charge; thisis in general estimated at 4 of the weight of the thot forlarge guns, and half of the weight of the shot for guns ofsmaller calibre The common charge for 13 inch mortars,including that of the lhell, is t glibs, of powder ; fi^lbs. forthe 10 inch mortar, and ^ibs. for royal mortars ; the chargefor the stone mortar is ^Ibs. of powder, and for hand gre-nades, 3 t°z.

23. When artillery, stores, Sic. are transported by land,oxen, horses, and sometimes mules, are used for drawingthem. ■ The weight that two oxen will draw on tolerablylevel ground, is about q cwt. two horses or mules will drawabout 74 cwt. : in hilly countrie. 1 , the weight should be dimi-nished by a fifth.

The weight in cannon being more concentrated thanin common carriages, five pair of oxen are harnessed to a16 pr. mounted on it’s carriage, weighing 36^ cwt.; whereas,four pair would suffice, if the weight were divided into fourequal parts. In mountainous countries, the ammunition,tools, Scc. are carried on beasts of burthen : a commonmule will carry a weight of 2-V cwt. and a full load for oneof the strongest, is 2} cwt. bur every article that exceedsj J- cwt. should be put into carriages. It is much moreexpeditious and ceconomical to make use of boats, if therebe any rivers or navigable canals in the country, that theconvoys are to pass through : to determine the number,the st we of the boats must be known, and the soundings ofthe rivers ; as the freight of cac^ must be proportioned tothe depth of water.

24. To exemplify the above maxims, let us suppose ;

1. A fortified town N N (PI.. 1), is to be besieged inform: that the nature of the foil is favourable forcarrying on the approaches, and constructing the bat-teries ; and that the adjacent country is level, andQ. neither