InterLibrary Loan history -- (you can stop reading now :) --
there was some early centuries AD, but...
First practical was UCBerkeley <-> California State Library in 1894.
but first call for it...
"inter-library loan" vs. "interlibrary loan" Google Books Ngram Viewer data comparing across the full corpus (1870–2019), and it gives a real number: around 1925.
Here's what the data shows:
1870s–1910s: The hyphenated form dominates entirely — this matches Green's 1876 "Inter-Library Loan of Books" and the early ALA-era usage we found in Library Journal.
~1900s–1920: Both forms are climbing in frequency (unsurprising, as ILL practice was growing), with hyphenated still clearly ahead.
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Here's what the data shows:
1870s–1910s: The hyphenated form dominates entirely — this matches Green's 1876 "Inter-Library Loan of Books" and the early ALA-era usage we found in Library Journal.
~1900s–1920: Both forms are climbing in frequency (unsurprising, as ILL practice was growing), with hyphenated still clearly ahead.
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