Abstract: A gauge for determining whether a hole is within tolerances is disclosed. Such gauge includes a cylindrical portion proportioned to fit within a hole with a relatively close fit. A paddle is pivotally mounted within the cylindrical portion for rotation in opposite directions from a neutral position. The paddle is formed so that when it is in the neutral position it has end faces which are aligned with the cylindrical portion of the gauge and which fit into the hole with a relatively close fit. One diagonal dimension of the paddle is equal to the minimum diameter of an in-tolerance hole and the other diagonal is equal to the maximum diameter of an in-tolerance hole. Once the gauge is positioned within the hole the paddle is tipped one way to determine if the hole has a diameter at least equal to the minimum diameter of an in-tolerance hole and the other way to determine if the hole has a diameter less than the maximum in-tolerance diameter.

Abstract: A trailerable utility crane having a compound articulated mast to provide variable working configurations and foldable on itself to provide a relatively compact storage configuration as well as an extended length sufficient to load and unload a tow vehicle. Transport wheels for road travel are carried by the mast in a manner that allows the base of the crane to be lowered to the ground automatically with extension of the mast. The mast is supported for azimuthal movement on the base and outriggers for stabilizing the base are safety-interlocked with the azimuthal support.

Abstract: A multiple dolly system for transporting large loads in which individual dollies are simultaneously power-steered through a fluid linkage steering control. Castered wheels of the dollies are steered by fluid power actuators having appropriate ones of their working chambers connected in parallel circuit arrangements, wherein ground reaction forces on the castered steerable wheels are equalized by the tendency of the parallel fluid circuits and actuator chambers to reach a balanced minimum pressure, and whereby the wheels, seeking a path of least resistance, are self-synchronizing in their steering displacements.