There are 152 photos in the Boston Wharf Company Collection, and they are housed in the Boston Public Library Print Department. They were just posted online this month--a good reason for continuing to recheck old sources.
This photo of the New England Confectionery Company was taken from the bridge slip in Fort Point Channel at the corner of the Summer Street Bridge. It was taken between 1902-1907, but I'm thinking 1907 is more likely, since it looks like it includes the additional buildings that were constructed in 1907 (after the main building was constructed in 1902).
Click here to see how the building looks today.
