FIG. 1 is front top right side perspective view of a rotary mount lamp socket and base showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top plan view thereof, the bottom being generally unornamented;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a right side elevational view thereof; and,

FIG. 6 is a left side elevational view thereof.

The broken line portions of the bottom surface are for illustrative purposes only and form no part of the claimed design.