Printing Types: Their History, Forms, and Use - Volume 2
The pattern
This still is filed under Specimen as proof.
Define
A specimen (type, material, finish) is shown so the product proves itself under comparison.
Mechanism
Controlled display. Same conditions, side by side, no adjective required. The sample is the sentence.
Verdict
Buyers choose by eye or by hand and we can put the real thing in front of them.
Why it works
The volume swaps argument for exhibit at exactly the point where the story gets contentious, letting the nineteenth century condemn itself through its own trade documents. Putting a commercial sale bill next to a Plantin specimen flattens the hierarchy between fine printing and job work, which is what allows the industrial chapters to be read as history rather than snobbery. The numbered caption line under every plate functions as a footnote the eye can use, so a reader can enter the book anywhere and still know exactly what he is looking at and when it was made.
Steal this when
Use this when the second half of a long argument has to cover a period your reader already has opinions about. Stop asserting and start exhibiting, letting primary documents from the period do the indicting, with each one labelled precisely enough that the reader trusts the sequence.