What is water gas?

   Water Gas is a colorless gas that burns with a hot, blue flame. Water in the form of steam is passed over red-hot coke, forming hydrogen and carbon monoxide. The hydrogen and carbon monoxide are then passed through a retort in which carbonaceous matter such as resin is undergoing decomposition absorbing therefrom sufficient car¬bon to render it luminous when burned. The average composition of water gas is approximately: carbon monoxide, 40-50 percent; hydrogen, 45-50 percent; carbon di¬oxide, 3-7 percent; nitrogen, 4-5 percent.