There is an additional disadvantage associated with the filling machine
. It is well known that cylinders which appear to be physically identical have different volumetric efficiencies. The effect of this is that individual cylinders will fill different quantities of material into the containers. The trouble here is that there are statutory regulations which require that the minimum quantity within a specific container must not be less than that which the container is stated to contain. Thus it has been heretofore necessary to arrange that the quantity of material pumped by the cylinder with the lowest output is not less than the statutory minimum so that all the other cylinders are pumping more than is necessary and are actually filling too much material into the respective containers. When it is understood that a machine of this kind is capable of filling many thousands of containers each day the quantity of excess material filled becomes a heavy additional charge on the production cost and yet cannot be recovered in the selling cost.