Touching the Past on a London Visit: the Stanhope Molds and Plates

Glenn Fleishman
6 min readJun 23


Synchronicity is real. With a trip to London already planned for last week, I booked a research visit to St Bride Foundation’s printing library. Founded in the early 1890s and seeded with a remarkable printer and scholar’s works, the collection is unparalleled for 19th century and earlier research. In emailing the archivist ahead for pull requests from the shelves, she passed my list on to Bob Richardson, a long-time volunteer, the one-time interim library manager, and the man who knows where everything in the collection is. Did I want to look at the Stanhope stereotypes, I was asked?

Did I! I recently completed writing and revising a chapter for a book called Printing Things: Blocks, Plates, and Other Things that Printed — editors Elizabeth Savage and Femke Speelberg, Proceedings of the British Academy with Oxford University Press — with my contribution focused on printing molds and plates, called stereotype matrices and plates. These molds and plates allowed printers, and newspaper publishers in particular, to increase their print runs dramatically. While the real impact of this method didn’t kick in until a paper-based mold became viable in the early 1860s, the history stretches back to the early 1700s and possibly much further. (See my essay here on Medium, “Flong Time, No See” for more on the word and the subject matter.)

As part of the research for my chapter, I tried to survey all pre-1900 matrices and plates held in collections. As I wrote the chapter, I kept finding more and more, including rare examples from a Dutch success in the early 1700s (held at the Museum of Leiden) and a plate surviving an ill-fated Scot’s efforts that were allegedly sabotaged by printers (held at the University of Glasgow).

The Stanhope stereotypes were unexpected. Developed into a commercial production technique starting around 1805 by Charles, third Earl of Stanhope (1753–1816) — also the inventor of the iron hand press, another key 19th century printing improvement, and a host of other things — they aren’t listed in any holdings. St Bride’s obtained theirs in 1982 on loan from the Chevening Estate, the ancestral home of the Stanhopes, passed by the 7th and last earl of that name in the 1960s to the United Kingdom. The plates were apparently found in examining holdings at the estate that dated back centuries. (The property is now used by the Foreign Secretary at times and is called Chevening House.)

The so-called Stanhope process relied on plaster molds made from forms of type — full pages or smaller laid-out arrangements. A liquid plaster mixture was poured on the form in a special frame, then baked in an oven and removed. Liquid lead alloy could then be poured into the mold in yet another specialized frame, cooling almost instantly. The plaster mold would then be broken off and the remains of the plaster chiseled out. The result solid plate could go directly on press. Any number of molds could be made from the same plate.

This technique was used across the 1800s but still had significant limits — time, cost, and complexity, based on my research. It’s unclear how widely it was employed. The perfection by the early 1860s of a paper-based method, called flong, had a very quick uptake because a flong could be bent into a hemisphere and cast as a curved plate used on a high-speed rotary press. (Again, see my article above for more detail.)

I assumed from all my research that all plaster molds were lost. There were no records of them existing, though neither was there about the Stanhope plates. Because plaster molds were broken off plates, the only ones that would have survived would have never been cast. And why would those have been retained? It seemed implausible. Most plates from the 1800s through the 1940s were melted down in World War II to meet the demand for metal for the war. The Stanhope plates seemingly survived by being forgotten.

A stereotype plate of a page of Stanhope’s “The Principles of the Science of Tuning” (a system of tuning being one of his many inventions) held at the St Bride Foundation (shelf number 1647A, “2x Stanhope Stereo Plates).
A stereotype plate of the title page of Stanhope’s “The Principles of the Science of Tuning” (St Bride Foundation, shelf number 1647A, “2x Stanhope Stereo Plates).

Just before my trip, I decided to do another search for Stanhope plates and came across an April 2023 blog post at the Stationers’ Company (founded as a guild in 1403), also in London. Archivist Ruth Frendo had come across a set of Stanhope material similarly on permanent loan from the Chevening Estate and linked to my flong article!

Most incredibly, the collection included a nearly perfect plaster plate! I wrote Dr Frendo and was able to set up a time to view and handle the material the day after my St Bride visit. She had written the blog entry to try to drum up some interest in the mold and plates — it worked!

Plaster mold likely from 1805 of a page of “On Printing,” an unpublished work by Stanhope. The next three photos show details at angles to better reveal the depth and nature of the casting. (Image above and five following appear courtesy Stationers’ Company)

Stationers’ Company also holds stereotype plates made at the same time for a variety of works and projects.

Stereotype plates (this and the one that follows) for a label for Stanhope’s “Demonstrator,” a mechanical device that could perform certain mathematical operations (see below). This label was placed on the device. You can see in the crevices of the plate the remains of the plaster mold that weren’t picked out.
Note the plaster in the interstices
Stanhope’s “Demonstrator” (Science Museum Group Collection, object 1953–353, image used under CC-BY-NC-SA 4.0 license)

It was a remarkable thing to get my hands on this 218-year-old mold, still in excellent shape. I expect that it was made to show as an example rather than intended for casting.

The plate was apparently mended in the 1980s by the man responsible for arranging the loan, Herbert Smart (1915–1999), a member of the Stationers’ Company and a lecturer at what was then the London College of Printing, the descendent institution of the printing school portion of St Bride’s. Through Bob’s knowledge of what I was looking for, I was also able to review a huge trove of typewritten notes and other material that Smart had assembled and sent to St Bride’s in the 1970s to 1990s. He noted in those documents, “One of the very few plaster moulds that survived was broken, but I was able to restore it.”

Examining primary materials is a boon for any armchair historian like myself. What an incredible set of intersecting connections and chance led me to hold and photograph these milestones in printing history, so relevant to my current research.

Glenn Fleishman is a printing historian and technology journalist. He specializes in printing processes of the 19th and 20th century, including a very niche interest in how comics went from an artist’s hand to a printed page through all the intermediate production steps.



Glenn Fleishman

Technology journalist, editor, letterpress printer, and two-time Jeopardy! champion. I seem to know everyone #glenning