specially adapted for raising liquids from great depths, e.g. in wells

Pumps using positively or negatively pressurised fluid medium acting directly on the liquid to be pumped > the fluid medium being mixed with, or generated from, the liquid to be pumped > specially adapted for raising liquids from great depths, e.g. in wells

Pumps using positively or negatively pressurised fluid medium acting directly on the liquid to be pumped (using only negative pressure F04F3/00; jet pumps F04F5/00; siphons F04F10/00) > the fluid medium being mixed with, or generated from the liquid to be pumped > specially adapted for raising liquids from great depths, e.g. in wells