This unique sidewalk clock, embedded by Barthman Jewelers on the corner of Broadway and Maiden Lane in 1898, is a hidden gem of New York's former jewelry district. In 1946, it was estimated that 51,000 people unwittingly stepped on the clock between 11:00 a.m. and 2:00 p.m. each day. The clock, which was given a new face shortly after this picture was taken, still works today. (http://abcnews.go.com/blogs/headlines/2012/02/the-radical-camera-new-yorks-photo-league/)