Is there no evidence for "private eye" coming from "private i" as in private investigator? Maybe it's a backronym, and they weren't called private investigators then...
So: Pinkerton’s started in mid-19C. GDoS 1st use of 'eye': Pinkerton is 1900. OED/GDoS 1st use for 'private eye' is 1938. Which is a big gap esp. given proliferation of hard-boiled pulps. And into that gap 'private i' may fall. I have found one e.g., but it's in ‘Library of Congress Subject Headings’ Volume 4 for 2013 (may be in (far) earlier vols but search doesn't bring them up). Subhead: Private Investigators, sub-subheads: Gumshoes / Investigators, Private / Private Detectives / Privates eyes / Privates I's.
Is there no evidence for "private eye" coming from "private i" as in private investigator? Maybe it's a backronym, and they weren't called private investigators then...
So: Pinkerton’s started in mid-19C. GDoS 1st use of 'eye': Pinkerton is 1900. OED/GDoS 1st use for 'private eye' is 1938. Which is a big gap esp. given proliferation of hard-boiled pulps. And into that gap 'private i' may fall. I have found one e.g., but it's in ‘Library of Congress Subject Headings’ Volume 4 for 2013 (may be in (far) earlier vols but search doesn't bring them up). Subhead: Private Investigators, sub-subheads: Gumshoes / Investigators, Private / Private Detectives / Privates eyes / Privates I's.
Still can't find them 'in the wild'.
Thanks, this has always intrigued me!