Abstract: A roof vent for preventing the buildup of hydrogen gas produced by battery charging in a remote digital telephone cabinet is provided with a movable splash guard for blocking the vent outlet when impinged upon by water and/or wind, thereby preventing the entry of water into the cabinet. The vent also includes a weatherproof cover whose lower edge is formed with scallops or undulations to maintain air gaps between the cover and the cabinet roof.

Abstract: The coupling of the present invention is adapted for use with a micromanipulator and a pair of pipettes. The micromanipulator comprises a pair of elongated arms and linkage connected to the arms for moving the arms in a plurality of directions. The coupling includes a housing having an arm receptacle at one end and a pipette holding device at the opposite end. A ball and socket swivel is provided within the housing and comprises a movable socket member which is matingly engaged with a spherical ball. The ball is connected to the pipette holding device. A threaded bolt engages the movable socket member and is adapted to cam the socket member into frictional engagement with the ball so as to lock the ball and socket joint against movement.