In a siphon tube (1) of a reservoir, even when a front end of tube (1) is in the vicinity of the bottom of the reservoir, there is no fear that slurries are sucked by tube (1) which: reaches the bottom of the reservoir to draw a liquid contained therein out of the reservoir is characterized by a liquid-inlet opening (3) directed normal to a longitudinal axis of tube (1). Tube (1) has its front end formed into: an inverted T-shape provided with opposite end openings in a laterally extending portion thereof, each of which openings forms the liquid-inlet opening (3); or, an L-shaped curved form a front end of which forms an opening directed normal to the longitudinal axis of tube (1); or, is closed with a cap so that an opening is disposed adjacent to an upper surface of the cap to serve as the liquid-inlet opening.