Abstract: Apparatus for determining whether a liquid in a liquid reservoir is above a certain level includes suction means operable by a user to create suction when the user desires to determine if the liquid in the reservoir is above the certain level, a conduit extending from the suction means and adapted to be positioned in the reservoir so that a passage in the conduit which communicates with the suction created by the suction means opens into the reservoir above the liquid therein when the liquid is below the certain level, and indicator for indicating whether or not the passage in the conduit is opening into the reservoir above the liquid therein. The indication that the liquid is above the certain level is given by either observing that liquid is being drawn into the passage or that the passage opening is closed. This may be done by observing the liquid itself in the passage or an indicating reservoir, or observing the operation of the suction means which given an indication of flow into the passage.

Abstract: In a device for indicating the level of a liquid in a reservoir of the type which has a liquid receiving area to be positioned partially within the liquid in the reservoir, a liquid confinement tube within the liquid receiving area which may be moved from a liquid unconfining position to a liquid confining position when it is desired to measure the level of the liquid in the reservoir, a piston within the liquid confinement tube coupled to an indicator located outside the reservoir such that movement of the indicator causes movement of the piston within the confinement tube, the amount of movement of the piston and indicator indicating the level of fluid within the reservoir, and a spacer tube determining the length between the liquid receiving area and the indicator, the improvement of making the device adjustable over a range of lengths.