typecasting matrix identification

Can anyone identify what typecasting process these matrices are used for?



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They look like electrotyped Thompson mats.


Bob, If so, are they used for a machine or hand casting operation? Victor

The Thompson caster is part of the Monotype line of casting machines. It’s the simplest in operation and the smallest. If you had a hand mold that was made with the correct body height for the Monotype depth of drive you could hand cast from those mats. It’s hard to say definitively but I’d guess the face is Lydian, about 18 or 24 point.


Not Lydian, that’s a monoline sans-serif shown. Twentieth Century is more likely, but the numbers stamped on the mat will tell.
The foundry mats used in hand-casting are quite different from the flat mats used on a Thompson. I’d be surprised if anyone ever made a hand mold that could accomodate these.

I hesitate to comment, since I’m quite new to typecasting, but I don’t think that these are Thompson mats per se. Rather, they look to be regular Monotype display mats intended originally for the Monotype Type and Rule Caster (but used on various machines, including the Thompson).

The mats made specifically for the Thompson typically have the top left and right corners beveled (less commonly only one corner beveled), and the bevel cuts go straight down.

The matrices made for the Monotype Type and Rule Caster have their diagonally opposite corners beveled (as these mats do) and the bevels themselves aren’t cut straight down but rather are angled such that the bottom of the mat is larger than the top of the mat. (The US patent for this style of matrix and a holder for it is No. 904,510 (1908-11-24) to William Elmer Chalfant. Sometimes these mats will have this patent date on their back.)

Typically a Monotype display mat will have four numbers on its front. The upper left number is the body size in points. The upper right number is the Monotype series number (sometimes with a suffixed character). The lower left and right numbers have to do with machine settings on the caster. If you don’t have a Monotype specimen book handy, there is a table of Monotype numbers in the back of McGrew’s _American Metal Typefaces of the Twentieth Century_. A 1922 Monotype specimen book is also online on archive.org

The Thompson was developed as an independent machine in 1908. Monotype bought the Thompson Type Machine Company in 1929 and continued the manufacture of this machine (even though it competed with their own machines). It is quite a flexible machine, and can cast from many styles of matrices (with appropriate equipment), including this style. When casting this style of mat on the
Thompson the corner cuts are not relevant.

For further information on the Thompson, see:




I don’t know my Monotype machines as well, but I believe that this style of mat could be cast not only on the Type and Rule Caster but also (suitably equippped) on the Giant Caster and the Supercaster. (Someone please correct me if I’m wrong here.)

David M. MacMillan

David is probably right about the specifics here, but this style of mat was commonly used on the Thompson. It all depends on having the right mat holders and suitable mold. With them, the Thompson could cast from a wide variety of mats, even Linotype and Ludlow. The Supercaster has similar capability (but with larger range of sizes).

Wow, now that’s what I call a discussion. Thanks for the info from all. I am new to Briar Press and am impressed at the level of knowledge, expertise, and opinions.

I did find Skyline type last night after my post and found an image of that style matrix on one of Sky’s pages, so I emailed him. He replied back today indicating (in his words)they are Monotype Display Matrices, for use on Monotype Sorts Caster or Thompson Type Caster, normally boxed in sets of 72 or 77, covering all of the characters of the font. I found 8 or so of the sets as I clear out my hot metal shop and hope to be able to add to Sky’s inventory of type faces. His operation seems very impressive.

I am sure I will post more inquiries on things I find as to what they are. I look forward to more discussions across a variety of topics.