From this period, the science of artillery progressed rapidly, and various improvements were made in this arm of the service, such as the introduction of iron axle-trees, and high limbers for the carriages of field guns. The reduction of windage, (mainly owing to the invention of carronades), and the use of cartridges and elevating screws, which latter served to render the fire of artillery much more rapid and regular. ~Rifled ordnance 1774.~ The invention of rifled ordnance is claimed by a Dr. Lind and a Capt. A. Blair, late 69th regt. Experiments were made at Landguard Fort, 26th August, 1774, by which it was intended to prove that shot weighing 42lbs., in the shape of a pear, would do as much execution, fired out of an 18 pounder, with a third of the quantity of powder, as could be effected by round balls of the same weight, fired from a 42 pounder. ~Perforated and fluted shot.~ Sundry trials were also made with shot perforated through the centre, and spirally fluted on the surface, suggested by Professor Anderson, of Glasgow, in order to prevent the common aberration in the flight of shot. ~Leaden projectiles.~ ~Breech-loading Rifled cannon.~ There were different modes of charging the rifled guns; one was, after the powder was put in, to take a leaden bullet something larger than the bore of the gun, and grease it well; in ramming it down with an iron rammer hollow at one end, the spiral threads of the rifle entered and cut into the bullet, and caused it to turn round in going down, and on being shot out, it would rotate on an axis coincident with its flight. Another mode was to charge them at the breech, where an opening for the reception of the powder and ball was afterwards closed up by a screw; but some barrels were screwed off at the breech-end to be charged, where they were made stronger than common. ~Congreve’s rockets.~ The adaptation of the rocket to the purposes of war, by Sir William Congreve, in 1806, introduced a new feature into the artillery of this and other countries. ~Mr. Monk’s improvements.~ Recently, at the suggestion of a Mr. Monk, of Woolwich Arsenal, a quantity of useless metal has been removed from before the trunnions, and the thickness increased considerably at the breech end, where alone it was wanted. ~Mallet’s monster mortar.~ The monster mortars recently constructed by Mr. Mallet, of separate compound hoops, must be regarded as a triumph of constructive skill. The shell is 30 inches in diameter, holding a bursting charge of 480 lbs., and weighing when charged 1¹⁄₂ tons (3,360 lbs.). Value of shell charged, £25. Weight, without bed, 42 tons. Weight of bed, 8 tons. Total, 50 tons. ~Cavalli’s and Wahrendorff’s~