There are no known city directories from the 1870s, or from before 1884.
1884-1885 — Brewery, Zorn Philip, proprietor Michigan City Brewery, southwest corner of Oak, Ninth and Michigan, residence southeast corner York and Tenth.
– Zorn Charles, works at Ph Zorn, residence southeast corner of York and Tenth.
– Zorn Herman P, works at Ph Zorn, residence southeast corner York and Tenth.
– Zorn Robert P, works at Ph Zorn, residence southeast corner York and Tenth.

1890 — Michigan City Brewery, Ph. Zorn, Proprietor, residence southeast corner York and 9th.
– Zorn Charles, foreman M.C. Brewery, boards at southeast corner of York and 9th.
– Zorn Robert, cashier Michigan City Brewery, boards at southeast corner of York and 9th.

1893-94 — Zorn Philip, Proprietor of Zorn’s Brewery, 110 York, home at 601 E 9th.
Zorn Charles, superintendent Zorn’s Brewery, home at 601 E 9th.
Zorn Robert, secretary and treasurer of Zorn’s Brewery, home at 601 E 9th.

1897-98 — Zorn Philip (Sophia), president Zorn Brewing Co, home at 601 E 9th.
Zorn Charles, secretary Zorn Brewing Co, home at 601 E 9th.
Zorn Robert, treasurer, secretary and superintendent Zorn Brewing Co, home at 601 E 9th.

1905 — Zorn Philip, president of Ph Zorn Brewing Co., home at 601 E 9th.
Zorn Charles, treasurer of Ph Zorn Brewing Co, home at 601 E 9th.
Zorn Robert (Flora), secretary of Ph Zorn Brewing Co, home at 817 E Michigan.

1909-10 — Zorn, Philip., president of Zorn Brewing Co., corner of Ninth and York, home at corner York and Ninth, phone 576.
Zorn, Chas., treasurer Zorn Brewing Co., corner of Ninth and York, phone 576.
Zorn, Robt. P. (Flora), 1st vice president Michigan City Trust and Savings Co., also secretary Zorn Brew Co., home 225 E Ninth.

1913 — Zorn Ph. Brewing Co., Robert P Zorn, president, Frederick Vullmahn vice president and treasurer, Brewers and Bottlers, York NE corner 9th.
Zorn, Charles, residence 517 Pine. – no longer at the brewery. 
Zorn Robert P (Flora), President Ph Zorn Brewing Co., First Vice President Michigan City Trust & Savings Co., residence 225 E 9th

1916, 1917 & 1918 — Zorn Ph. Brewing Co. (Inc.), Frederick Vullmahn, of Chicago, Ill., president and treasurer; C.E. Remer, of Kenosha, Wis., secretary; Wm. Schmidt, sales manager, office York St., NE corner 9th.
Robert Zorn is no longer at the brewery.