When a boiler is in use, the gauge-cocks should frequently be tried to see that they are not choked up , and the glass gauge should often be blown out. After ascertaining the proper place for the weight on the lever of the safety-valve, a stick should be secured to the lever with wire, so that the ball can not be moved out any further. A cord should be secured to the safety-valve lever, within easy reach of the engineer, so that the valve can be opened by hand if it sticks, and the safety-valve should be tried at least once every day, to ascertain whether or not it is in working order.

A steam-gauge should be tested at least once a year, and the engineer should frequently try its accuracy by allowing the steam to raise the safety-valve, and noting the pressure shown by the gauge. The hand of a steam-gauge sometimes sticks, and the engineer should tap the face of the gauge lightly several times a day, to assure himself that it is in working order. He may also shut off the steam from the gauge pipe, and open the drip-cock, noting whether the hand goes back promptly to 0, and returns to the former reading when steam is again turned on.

In testing a boiler, warm water should be used, and a better test, when this is possible, is to enter the boiler and make a thorough internal examination.

In leaving a boiler for the night, the lire may either be hauled or banked. If it is to be banked, it should first be cleaned and then pushed back and covered with coal, the boiler being left with the furnace-door open and the damper closed. B.