The Glass Water Gauge

The first duty of the engineer is to see that the boiler is filled with water. This he usually does by looking at the glass water gauge. There is a cock at each end of the glass tube. When these cocks are open, the water will pass through the lower into the glass tube while steam comes through the other. If the glass breaks, both upper and lower gauge cocks should be closed instantly. In addition there are dry cocks for ascertaining the level of the water in the boiler. Dry cocks are often called gauge cocks. The steam gauge is a delicate instrument arranged so as to indicate by a pointer the pounds of pressure which the steam is exerting within the