Benthograph operations, Velero IV, Santa Catalina, 1949-1950

"Velero IV 49-50, benthograph (orig[inal])". Various scenes with the benthograph (both close and far shots), the scientific equipment it contains, being loaded into it, its hatch being secured, being winched into and out of the water over the side of the Velero IV (ship) into the water in Avalon Bay, Santa Catalina Island. In most of the scenes are Captain Allan Hancock (wearing captain's hat), Dr. Maurice Nelles explaining the equipment, possibly Perry Stilley assisting with the equipment, a photographer and cameraman are also in the scene at in few places. Several people approach in a rowboat, a motorboat races by. Similar raising and lowering operations of the benthograph in a different location with some different people present.