When charging a cylinder from a machine, it contains air. By opening the jet cock F, the gas will detonate itself by its pungent smell. Close the cock, and continue pumping both gas and solution until the valve H lifts. You must then open the jet cock and if it only blows gas out shut it immediately and continue pumping until the water reaches it. It will be at its correct height. Shut the cocks at G and P then it may be removed. The connection G attaches it to the machine while filling it, as well as the fountain afterwards.