Abstract: A self-storing step structure for vehicular mounting including a first step section, means for pivotally connecting the first step section to a vehicle for pivotation about a horizontal axis between an operative position and a stored position, an extensible step section slidably engaging said first step section, and means for adjustably interlocking said first step section with said extensible step section at a preselected relative location.

Abstract: Petroleum may be recovered from subterranean, petroleum-containing formations by injecting into the formation an organic liquid having dispersed therein, an alkali metal in very fine, preferably colloidal size range, particular form. The organic liquid containing the alkali metal dispersion is followed by injecting an aqueous fluid to react with the alkali metal, generating alkali metal hydroxide, hydrogen gas and heat in the formation which stimulates displacement of the petroleum by encouraging formation of low viscosity oil-in-water emulsions, as well as by thermal viscosity reduction effects, and dissolution of hydrogen gas in the viscous petroleum. The organic liquid having alkali metal dispersed therein may be preceded or followed by injecting crude petroleum from another formation which is prone to emulsify spontaneously and aid in the formation of low viscosity oil-in-water emulsions.

Abstract: A self-storing step structure for vehicular mounting including a first step section, means for pivotally connecting the first step section to a vehicle for pivotation about a horizontal axis between an operative position and a stored position, an extensible step section sidably engaging said first step section, and means for adjustably interlocking said first step section with said extensible step section at a preselected relative location.