In 1893 there were about ten different types of bases used on lamps manufactured in the United States. This resulted in the inability to use lamps of different manufacture in the same socket. An attempt to reduce this problem was made by the Universal Pull Socket and Switch Company, 27 Beaver Street, New York (Electrical World, Vol XXII, No 18, Oct 28, 1893, pg 349). They marketed a socket in which lamps with Edison, Westinghouse or Thomson-Houston bases could be used. This socket, scanned from the Electrical World article, follows.

"To turn off a lamp it will be seen that it is only necessary to pull the cord or chain, of which the pendent ball at its lower end may be a luminous one, thus facilitating turning on the light in a dark room. The pull always returns to its original position when released.

The socket is adapted for use with the Edison, Thomson-Houston and Westinghouse lamp bases, and makes and breaks the circuit by merely pulling the cord or chain, whether the lamp be arranged to project upward, downward or laterally, as shown in the cut. For the Thomson-Houston base no adjustment is required; all that is necessary (is) to screw the central split screw of the socket into the screw hole in the front of the Thomson-Houston lamp. For the Edison base the screw neck illustrated must be inserted into the socket to do this. The two opposite screws in the bottom of the top cavity of the socket are slightly loosened, and then the screw neck is inserted in such a manner that the heads of the screws can pass through the diametrically opposite notches in its bottom flange; the neck is then given a quarter turn so as to cause the two hook prongs to pass under the heads of the screws, which, when set up light, secure the neck in position, and an Edison base lamp may then be screwed into the socket as usual. For the Westinghouse base the spring neck is inserted, as shown in the cut, and fastened in the same manner as the screw-neck for the Edison base. The lamp is then inserted and is held by the several prongs of the split spring neck, the pin on the foot of the Westinghouse base passing into the split hollow screw in the 'Universal Socket,' thus making the proper connection."