A printed table which enables a tank owner to convert depth of liquid in a storage tank to the number of gallons remaining in the tank. 

When an tank owner withdraws a gauge stick from a storage tank, he records the number of inches reached by the liquid level in the tank. This number might be, say, 4 feet and 11 inches. That’s the depth of gasoline or other liquid in the tank. But how does this figure translate into gallons? If the tank is a 10,000-gallon tank, how many gallons are represented by a depth of 4 feet and 11 inches? 

The most common way of making this conversion is through reference to a printed chart. Separate charts are required for tanks of different lengths, diameters, and configurations. For example, a conversion table designed for a steel tank with flat ends could not be used for a fiberglass tank of the same capacity with convex ends.