Cat. & Reference: The librarian as detective
Last Thursday I found that I had to catalogue two pamphlets published by the American Woolen Company. At first glance, the two pamphlets looked almost identical. They were both called "Properties of the American Woolen Company" and they consisted of unnumbered pages of photographs of woolen mills in the New England area which were owned by that company. Neither book contained a copyright date, although I guessed that they were from the early part of the 20th century.
As a cataloger, if you don't have a lot of information to go on, it's perfectly legitimate to take your best guess and move on, even if that best guess is very vague. (E.g., you can record something like [19--] or [ca. 1930?] in the date field.) However, I like to provide as much information as I can, even if it means doing a little detective work.
Upon closer inspection, however, I realized that one of the books contained 38 photographs, while the other one contained 54. Presumably, the second book had been published some years after the first one, and the 16 additional properties had been acquired in the meantime. I realized that if I could figure out when those additional mills had been acquired, I'd have an upper date boundary for the first pamphlet and a lower date boundary for the second.
So my first task was to record and organize all of the mills mentioned in the two pamphlets. (There was no table of contents, and they didn't appear to be organized in any logical fashion.) Many of the mills had very generic names which made them hard to research, but I found one, the Waverly Mill in Pittsfield, Maine, which had been acquired by the American Woolen Company in 1914.
In the process of doing this research, I found a Wikipedia article about the American Woolen Company which mentioned that they acquired the Ayers Mill in 1909. Since that mill appeared in both pamphlets, I could use 1909 as a lower boundary for the date range, meaning that I'd narrowed down the dates of the first pamphlet to between 1909 and 1914.
In the second pamphlet, I found a mill listed as the Foxcroft Mill in Foxcroft, Maine. The town of Foxcroft no longer exists, because in 1922, it merged with the town of Dover to form Dover-Foxcroft. This meant that the second pamphlet had to have been published before that date, so I could give the date range of the second pamphlet as between 1914 and 1922. (Not quite as narrow as the first range, but still better than [19--].)
Cataloging both of these pamphlets took about an hour, but sometimes you have to go the extra mile.