Plaques: Creamery Bridge

Have you ever seen the historical plaque below? It is just south of the College Street bridge, on the west side of the street. It tells us that the present bridge structure is the third on the site. The first was a bowstring bridge, and I do not understand from the text if the first bridge at this site was in 1891, 1896, or 1908. (If you can make sense of this, leave a comment.) The bridge of 1958 was replaced about ten years ago. (Was it 10, 15, something else?) I do remember that during construction there was a time that the only thing spanning the river was an I-beam used by the workers, and that for a month or there were a number of days when I took a shortcut and crossed that I-beam.

This plaque was on the 1958 bridge and was reset when the current bridge was put in. If you cannot read it, it reads:
Creamery Bridge
Near the Separated Butter Co. Building S.W. of site, erected 1891 original bowstring span hereon (Milroy St.) 1896 reset by Iroquois River Improvement 1908 replaced by concrete bridge 1958
Emil W. Hanley, Mayor
Council
Gordon E. Bausman James W. Critser Albert L Toben Joseph G. Ferguson Rex O. Blacker
Engineer Raymond L Paulus
City Attorney John E Hopkins
City Engineer Hugh Thompson Kirk
Clerk Treas. John R. Merritt
Street Comm. John L Wartena
Contractor David Hornback, Jr

When was the Separated Butter Company in business?
(Sorry. I have a lot more questions than answers today.)