Abstract: The invention relates to an apparatus employing pressure transients for transporting fluids comprising at least one partly enclosed space (201,301,501,601,606,701,1101,1201), at least one body (202,302,502,602,607,702,1102,1202) in said at least one partly enclosed space, where said at least one body is movable relatively to the interior of said at least one partly enclosed space, at least one opening (204,205,304,404,504,604,605,704,705,1104, 1204) in said at least one enclosed space which allows a fluid to flow alternately in the direction into and out of said at least one partly enclosed space, at least one first conduit (211,311,411,511,513,611,711,1111,1211) and at least one second conduit (212, 312,412,512,514,612,712,1112,1212) in fluid communication with at least one of said at least one opening, at least one first reservoir (231.331.431.531.533.631.731.1131.1231) and at least one second reservoir (232.332.432.532.534.632.732.1132.