It may prove elusive to locate just exactly the imagery you are looking for on the Internet, or by searching for books in the library catalog. The Central Library Picture File Collection helps solve this problem. For many years (starting long before the Internet!), books beyond repair, outdated calendars, and discarded magazines were reviewed by librarians and organized by volunteers into massive file cabinets of pictures, all by subject.
The composite picture shown here is from the file of womens' fashion from 1950, just the single year 1950. Womens' fashion design is one of the most extensive sections, with a file for each year from 1900-2005. There are picture files for hundreds of topics from the arts, history, social sciences and natural sciences.
Pictures can be checked out just like books. To use this collection, ask for picture files at the Central Library Art and Music Reference Desk, on the third floor. You can check out up to 50 images selected from multiple folders.
The individual pictures are all protected by copyright laws of the US, since they are from printed books and magazines, published after 1922. As such, the goal of the collection is for helping people shape the ideas for their projects.