New apparatii and processes are disclosed to create fluid continuity between opposite ends of a route drilled or bored under and/or around an obstacle. This invention allows fluids to be pumped through a reamer and a hollow swivel from either or both sides of the obstacle. It also allows the direct transfer...http://www.google.com/patents/US5176211?utm_source=gb-gplus-sharePatent US5176211 - Apparatus and method for recirculating mud when drilling under an obstacle
