PURPOSE: To make a small difference of quantity readable with a manometer, by attaching a fine and long pipe section permitting no continuous replacement of air in connection with a liquid sump of a lifting type liquid measuring apparatus and lifting up liquid from both liquid sump and pipe section.

CONSTITUTION: A pipe section 8a installed in connection with a liquid sump 8b is provided with a small diameter end preventing replacement of liquid by air. The liquid sump is connected with syringe and manometer 7 through fitting 1, flexible pipes 2, 3 and 6, and T-fitting 5. The syringe 4 is operated by inserting the end piece of a pipe 8a into the sample liquid, while the sample liquid is lifted up, covering liquid sump 8b and pipe section 8a. When the top level of the liquid in the sump 8b is kept constant, an infinitesimal difference of the liquid is represented by a difference of the length inside the pipe section 8a and so, the difference of depression in side the manometer is enlarged. By this arrangement, a difference of infinitesimal quantities of the liquid is indicated by the manometer 7 accurately.