From The Chicago Public Library Staff News, v.3:no.3, Nov. 1924
This is addressed to the Juniors–you who come to us in such numbers, usually on temporary appointment until the next Civil Service examination, which you must take and pass before you can begin to be promoted. You come into our staff, mostly, straight from school or college and have never been regularly employed before. Usually you were led to seek employment with us because you thought you would like our kind of work, or because someone else who directed you thought you would like it, and that your tastes and capacities fitted you for it.
We hope you do like it, and find it interesting and congenial. If you do not, you are wasting your time here and we are wasting ours in trying to teach you even the simple duties of the positions to which you are assigned. You are just beginning at the bottom of what really is a very fascinating and somewhat complicated kind of work, and your part of it for the time being is quite apt to appear both simple and mechanical. But you are a part of a big machine which works smoothly only when all of its parts work smoothly together. If your part goes wrong the whole machine may go wrong. If, for example, in charging books, you copy a borrower’s card number incorrectly, say, by writing a 6 where an 8 ought to be, you are charging a book to an entirely different person from the one to whom you gave it at the desk. And if it would become overdue, our notices would be mailed to an innocent party, who would have a right to feel offended and to hold a very low opinion of the Public Library. Your acts or your conduct in general may, thus, become a direct cause for making or marring the reputation of the Library as a public institution.
Truly inspiring. Really makes you want to be a librarian, doesn’t it?
These lucky juniors would likely enter a training program with the public library. Some of the more fortunate ones attended library school, whereas people hired as library clerks had no opportunity for promotion without formal training. Entrance to the public library’s training program required a high school diploma and a passing score on this exam (There are two pages. Click on the image for a pdf):