Care of Materiel. (a) Parts of the Carriages. All nuts are secured by split pins, which should be replaced and properly opened when nuts are screwed home. Do not strike any metal part directly with a hammer; interpose a buffer of wood or copper. All working and bearing surfaces of the carriage require oiling; those not directly accessible for this purpose are provided with oil holes closed by spring covers or handy oilers. Do not permit brake levers to be released with a kick or blow. It has been found that the apron hinges occasionally become broken, and that the apron hinge pins are frequently lost. Whenever this happens the hinge or hinge-pins should be immediately replaced. For if this is not done the apron, which is very expensive is apt to become cracked or broken. When the lunette becomes loosened the lunette nuts should at once be tightened. (b) Wheels. Keep hub bolts and hub bands properly tightened. To tighten the hub bands screw them as tightly as possible with a wrench and then force them farther by striking the end of the wrench with a hammer. All wheels and pintle bearings should be frequently oiled. (c) Inspections. Battery commander should frequently make a detailed inspection of all the vehicles in the battery, to see if any parts of them are broken or if any screws, nuts, split-pins, et cetera are missing. If any such defects are found they should immediately take steps to replace missing or broken parts. At these inspections the material should also be examined to ascertain whether the cleaning schedules have been properly carried out. Compliance with these instructions will do much toward prolonging the life of the carriage. Firing, Precautions and Preparations for. Before firing, inspect to see that cylinders are properly closed and that the cylinder end stud nut and piston rod-nut are in place. If time permits, oil slides before firing. Note length of recoil for the first few shots to be sure that the recoil mechanism is working properly. There is no danger as long as the recoil does not exceed 48 inches. Therefore, for first shot always set recoil indicator for about 42 inches. If the gun fails to return fully into battery, it is probably due (1) to dirt on slides and guides, (2) to cutting of slide surfaces on account of lack of oil, (3) to gland being screwed up too tightly, (4) to dirt or foreign particles in the cylinder, and especially in the counter recoil buffer recess, (5) to weakness of springs, 90% of such cases will be found to be due to 1, 2 or 3. Lock the cradle to the trail at drill and at traveling to avoid unnecessary strain upon the pointing mechanism. After unlimbering, release elevating and traversing lock before attempting to elevate or traverse gun. Cleaning and Care of Leather.