Sampling method and apparatus

A sampling apparatus comprising a helical tube means which is open at one end of the helix and vented to the atmosphere at the other end, means for supporting said helical tube means for rotation about an axis which inclines upwardly from said one end of the helix,

• means for rotating said helical tube means about said axis whereby to swing said open end thereof about an upright circle concentric with the rotative axis of the tube means and in the direction in which the open end of the tube means faces forwardly in the direction of rotation, and means providing for immersion of the open end of the helical tube means in a liquid as the open end of the tube means swings through a lower portion of said circle,
• said means for rotating said helical tube means about said axis including intermittent drive means whereby the open end of said tube means is moved through the lower portion of said circle at one rate and through the upper portion of said circle at a substantially different rate.

The method of obtaining a series of fluid samples which comprises

• rotating a helical tube means having a wall of flexible material about its helical axis while passing an open end thereof successively through first and second fluids of respectively different densities and thereby screwing a plurality of slugs of the first fluid separated from one another by slugs of the second fluid into the tube along the length thereof, and pinching together the inner sides of the tube means walls on at least one side of each convolution so as to seal off the interior of each convolution from the next adjacent convolution, thereby preventing intermixture of the successive sample slugs.