The J stands for Joseph Wittmann.
Joseph Wittmann, Queens Ward 4, appears in census records from 1900 to 1930. Over that period, he listed himself as a bottler, proprietor, manufacturer and retail merchant of mineral/soda water. According to a September 28, 1940 Brooklyn Daily Eagle article announcing his death, Wittmann was born in Brooklyn and lived in Queens for 46 years. He died in 1940 at the age of 76.
The business apparently started in Brooklyn in the late 1880’s. Joseph Wittmann, bottler, was listed in the 1889 and 1890 Brooklyn directories, with an address of 729 Flushing Avenue. He was not listed in the 1887 Directory.
Sometime between 1891 and 1898, the business moved to Thrall Pl, corner of Broadway, Woodhaven, where it’s listed in the 1899, 1903,1907, 1908-1909 and 1912 Trow Business Directories of the Borough of Queens under mineral water. It was also listed in the Brooklyn, Queens and Staten Island Section of the New York Telephone Directory as Carbonated Beverages through at least 1928. By this time, the address was 97-40 91st but I don’t think the location changed because Thrall Place was renamed 91st Street. Based on the census records the business could have lasted into the 1930’s.
I found three mouth blown bottles, all embossed “Woodhaven”. Two are large (28 oz); one has a tooled blob finish and the other a tooled crown finish. The third is smaller (8oz) with a tooled crown finish. The larger bottles used slug plates while the smaller one is a private mold. All three fit the earlier years that the business was in Woodhaven
I’ve also observed machine made (28oz) bottles in the bays as well.