Why do so many listings say 18th century with no year?

Only 236 of 840 listings carry a clean year, so most dating here is done by period label rather than by date. Titles reading "18th Century" or "19th Century" are best read as a bracket. The dated field runs 1700 to 1960. The 18th century is the largest single label, followed by the 19th, with a further group given only as "1800s".

What does after mean in an engraving title?

It means the print reproduces a design by the named artist, who didn't cut the plate. Reynolds, Hogarth, Kauffman, Morland, Claude Lorrain, Rubens and Raphael all recur as source names. About a fifth of titles use it, and those prints make up a much larger share of the top of the range, especially where the engraver is named too.

Are engravings usually sold singly or in sets?

Both, but multiples are close to the norm. "Pair" appears in 101 titles, "four" in 56 and "six" in 26. The largest group recorded in a single sampled title is a set of twenty-seven Regency hand-tinted prints. Sets and long panoramic sheets hold the top of the range.

Which subjects come up most often?

Portraits of titled sitters, largely as mezzotints. Hand-coloured natural history: birds, fish, insects, monkeys, serpents, shells and skulls. And large architectural plates, with 26 titles mentioning Athens and 24 "antiquities". Cries of London is the most repeated single subject in the samples, turning up in five separate listings in different editions and set sizes.

Do wood engravings appear under this heading?

Yes. Wood engraving is cut into the end-grain of a block and printed in relief, so it isn't intaglio, but it's catalogued here all the same. A tight 1930s group accounts for most of them, seventeen titles referring to wood engravings from a single 1935 book, Four Hedges, each a mounted individual leaf. They sit at the bottom of the range.

What unusual forms turn up in this category?

Reverse engravings on glass, prints under verre eglomise and hand-coloured optical prints all appear once or twice and nowhere else. So does a run of anatomical plates, skulls, skeletons and a rhinoceros skeleton among them. An engraved wine glass has been filed with the prints. A few lithographs and maps sit under the heading as well.