Not sure what yours held but Asco is a precursor to acme...
I think Josh has nailed it.
Asco stands for American Stores Co. This was a house brand of what would later become Acme Markets.
"The name of the new entity was first announced to the public on April 2, 1917 when The_ North American, a predecessor of The Philadelphia Inquirer, made known the organization of a new grocery chain in Philadelphia with the name of American Stores Company. (The same edition of this paper also carried the report that President Woodrow Wilson would go before the Congress that day to ask for a declaration of war against Germany...
This year marks the centennial for a venerable institution which has conducted a grocery store business in Tredyffrin and Easttown townships since at least the 1920s. American Stores Company, the parent of Acme Markets, was formed in 1917 with the merger of five Philadelphia chain store businesses, but it traces its beginnings back to a single store, opened in 1891 by one of its predecessors, Robinson & Crawford."
TEHS - Quarterly Archives
There's an FOHBC article on Capstan Glass & Asco, right here:
http://www.fohbc.org/PDF_Files/CapstanTumblersJarsBottlers4AmerStoresCo.pdf
"Juice, Asco, grape, .23/pint bottle
Olives, Asco, stuffed, .10-.20/bottle
Soda, Asco, ginger ale, .25/three bottles
Tea, ASCO, black, .23/half lb pkg"
Morris County NJ historic price survey 1908-2008
http://www.treasurenet.com/forums/bottles-glass/235778-weekend-dig-part-2-updated-better-pics.html