The death of a possible descendant has cast thoughts back to the inventor of one of the enabling technologies of the letterpress era… and created a new mystery.

It started with a note to John Cornelisse, who is a moderator on Dave Hughes’ metaltype.co.uk website forum.

Heidi Luo was letting us all know that her husband, Ludwig Mohr had died the previous Sunday (presumably January 9). Nothing more, apart from her email and cellphone number.

Another moderator was quick to make the connection with the inventor of the Mohr saw and (it seems, wrongly) the quadder, two enabling technologies that turned the linotype “from a line casting machine into a composing machine”.

But Ludwig Mohr – remembered by some from the ATF (American Type Founders) conference and “in his sixties” would have been too young to be the inventor of the lino saw, which appeared – according to a back copy of Printing magazine – in 1912. Son or even grandson, we thought; nephew perhaps.

Most of us with an interest in the letterpress process have recollections, of the Mohr Saw, the quadder and Hydraquadder which superseded it. As a boy, I remember a Fleet 54 Linotype being delivered on my tenth birthday to the print works in Sheerness, UK, where my parents ran the local paper. As all the linos were on the first floor, it had to be taken apart to be manhandled up the stairs.

And in 1959, during the UK printing dispute, we took a delivery of a Model 78 with all the bells and whistles – Mohr saw, Hydraquadder and paper tape reader unit – which had come directly from a trade show in Dublin. For reasons I needn’t explain, my father was particularly anxious that no-one knew where it was being installed!

At various points we ran both under tape control and (at times) at high speed, though without the benefit of the little PDP8 computers that took the uncertainty out of justification. Paper tape lived on with us into photocomposition, driving our early Compugraphics and edited from week to week on AKI (Automix) terminals.

At the end of the nineteenth century, Ottmar Mergantheler (b. 1854 in Bad Mergentheim, Germany; d. 1899 in Baltimore, Maryland, USA) was the inventor of the greatest letterpress enabling technology since Gutenberg’s of printing… the Linotype hot-metal linecaster. Mohr’s contribution was to make it work better.

The quadder – and later hydraulic Hydraquadder – held (and enabled the casting of) lines of linotype matrices and spaces flush to the left (“quad left” for FLRR), right (“quad right”) or centred, without an operator filling them out with spaces and spacebands.

Changeable moulds installed in the linotype determined the length of a line of type within the capability of the machine. Mohr’s invention of the lino-saw made it possible to set type to a short measure and physically cut the slug to the size required, a big timesaving for display typesetting where picture blocks had to be placed within or alongside a column of type.

As far as we can establish, the inventor of the Mohr saw – and founder of the Mohr Lino-Saw Co in Illinois – “invented the saw in 1912” and went to Chicago where he established the company. He was survived by a widow and a son, Harold O. Mohr who – according to Printing magazine in 1941 – was vice-president. Mohr senior was born in El Paso, Illinois, in 1868, the son of an Evangelical Church minister, and we’re pretty certain he’s the Charles L. Mohr of Janesville, Wisconsin, in whose name the August 1912 patents for the Linotype “slug saw” and “slugcutting attachment for Linotypes” were granted (and then assigned to Mohr Manufacturing Company of Chicago).

In 1956, Inland Printer was reporting that the company “showed a substantial increase in shipments” over the previous year, and was expecting the high level of sales to continue in 1957.

We haven’t (yet) confirmed the family connection Metaltype followers were looking for. Ludwig Mohr came from Germany with qualifications in typesetting, letterpress, hand bookbinding and printmaking on copper plates, which he would teach from a base in Maywood, California, skills reported in ShoutOut LA and VoyageDallas in 2021 and 2019. However, his widow, Heidi Luo assures me he was not the son of Harold Mohr, so the connection – if there is one – remains a mystery.

She, incidentally, is a celebrity in her own right, listed in IMDb.com as “clean comedian, actress and educator” having been born in Shanghai before coming to the US, where it appears she met Ludwig Mohr through a local MB club.

We’d love to know more, and if readers can fill in the gaps, please log in to comment or email me.

Peter Coleman