We have a Porcelain Ceiling Light with outlet on side Vintage item.  It measures about 4 1/2" across the center x about 2 1/2" in H.  The light socket opening is about 1 5/8" (outside measurement, inside is about 1").  There is a metal pull chain with some sufrace rust.  I cleaned this quickly, it will need a bit further cleaning.  It will need to be rewired.  I did not see/feel any chips.