original early 20th century american arts & crafts or craftsman style interior residential single electric light pendant lamp, possibly fabricated by or for r. williamson & co., chicago, il. the c. 1910-15 mission style lamp retains the original green slag glass panels or insets mounted under a stepped pyramidal-shaped top. the original brass chain and circular-shaped canopy are intact. the craftsman light fixture has been rewired with period appropriate braided cloth cord. the brass fixture with overlapping flat straps have a nicely aged surface patina left untouched. the single socket is in great working condition. measures approximately 5 1/4 x 5 1/4 x 8 1/2 inches.