Abstract: A lubricant composition of a synthetic oil of lubricating viscosity, 3 to 6 percent by weight of a nitrogen-containing dispersant, 1 to 2.5 weight percent of an overbased magnesium detergent, 1 to 5 weight percent of an antioxidant; and 0.25 to 1.5 weight percent of a friction modifier is useful for lubricating a hydrogen-fueled engine. The composition will typically contain less than 0.01 weight percent Ca, less than 0.01 weight percent Zn, less than 0.06 weight percent P, and will have a sulfated ash level of less than 1.2%.

Abstract: A lamp capable of underwater use comprises a rectangular acrylic body with elongate V-shaped recesses in a major surface each receiving an elongate Beta-light. An acrylic cover plate is sealed to the major surface and the body is secured to a steel backing plate with a neoprene layer between to help dissipate shock loadings. The sides of the recesses include an angle of 78.degree. to enhance reflection and may be formed by a reflective lining. The Beta-lights can be received in the grooves by shock absorbent O-rings grouped in pairs with adhesive in between. In a modification a disc-shaped Beta-light is encapsulated and received in a body formed by pour molding which is closed by a cap which is ultrasonically welded into place.