When this factory was built in the early 1920s, Ridley's was well-established as the oldest confectioner in New York. Founded in 1806 at 1 Hudson St., Manhattan, the company had expanded to a second, "up-town" facility at 1149 Broadway, near Madison Square Park, by the time of publication of 1872's Great Industries of the United States.
That book roundly praised the quality and purity of Ridley's "numerous and varied" ingredients, "a singularly agreeable array of things wholesome, flavorsome, delicate, and aromatic. They include, first and foremost, sugar; then the auxiliary substantials of honey, molasses, cream, gum arabic, almonds, filberts, cocoanuts, peanuts, chocolate, licorice, jujube, flax seed, coriander seed, caraways, cinnamon (i.e, the cassia of commerce), cloves, and Iceland moss. Next are the flavors, which are birch, boneset, cayenne pepper, cinnamon, ginger, hoarhound, lemon, musk, peppermint, raspberry, rose, sassafras, vanilla, and wintergreen."
As to the time and manner of Ridley's demise, I can't say. Current leads on local birch candy are equally elusive.
Surviving signage on 34th St. between Queens Blvd. and 43rd Ave., Long Island City, Queens