_Field Howitzers_ use high-angle fire, giving a large angle of descent, so that they can search out the enemy’s trenches. They are provided with high-explosive shell in addition to shrapnel, so as to destroy masonry and field works, which the shrapnel of field guns cannot injure. Both these varieties of Field Artillery have their Officers and Sergeants mounted, and carry their men seated on the gun limbers, or on the wagons, so that they can move at a trot. _Horse Artillery_ is provided for supporting Cavalry in action. It is armed with a lighter nature of field gun, and has its personnel mounted, so as to be very mobile. It can keep up with Cavalry both on the march and in action, and can move at the gallop when required. HEAVY ARTILLERY This comprises the heaviest guns and howitzers having sufficient mobility to accompany an army in the field. It uses shell filled with a high explosive, as well as a large shrapnel, and is therefore effective against field works and masonry as well as against men and horses. It differs from Field Artillery in having less mobility, but longer range and much greater effect. It generally comes into action at long ranges, and changes its position as little as possible in action. It will be very effective against the enemy’s artillery and field works, and its great range will allow it to bring oblique fire on the vital portions of his line. Heavy Artillery is manned by the non-mounted Branch, called _Garrison Artillery_ in England, and _Foot Artillery_ abroad. It requires eight-horse teams, and moves only at a walk, the men marching on foot. MOUNTAIN ARTILLERY Artillery carried on pack animals is used in hilly, enclosed, or rough country, where wheels cannot pass. It is the weakest form of Artillery in shell-power, as it is armed with a light gun, which can be carried on a pack mule. A heavier gun can be carried, if formed of two parts, each about 200 lb. weight, or a load for one mule, which can be jointed together for action. The gun carriages, ammunition, and stores are also carried on mules, and the personnel marches on foot, and is provided from the “Foot” (or “Garrison”) Artillery. The slowness of Mountain compared to Field Artillery is compensated in broken country by its ability to take cover, and to come into action in places inaccessible to Field Guns, so that it can support Infantry more closely. THE BATTERY The Tactical Unit of Artillery is the _Battery_, of 4, 6, or 8 guns, with 1 to 3 Ammunition Wagons to each gun. Field guns and wagons have six-horse teams; Heavy Artillery has eight-horse teams. In France, Switzerland, Turkey and the United States all Batteries are of 4 guns. In other armies all Field and Horse Artillery Batteries are of 6 guns, except in Austria, where Horse Artillery has 4-gun Batteries, and in Russia, where Field Batteries have 8 guns.