Printers are a funny lot.
In a printer's workshop there is little as reassuring as the
measures. As such this would be a fact easy to understand if
it were not for the other, rather more incomprehensible, fact
that this 'fact to murder for' has never seen the light of international
agreement. To begin with it was as exact as any measuring with
the local 'length of an arm', or foot, if you like.
Pierre Simon Fournier (1712-1768) was (in France that is)
the first to have his typographical units - based on a 'less
common' foot - 'approved of by many'. His 'approximate pouce'
(something like a foot) was divided by 12 to have a 'ligne',
which is to be divede by 6 in order to have a 'point'.
François Ambroise Didot modified that 'less common
foot', and made Fournier's typographical base unit precisely
fit a 'pouce' - which has to do with some French Royal inch somehow.
This practise made the Didot point exactly 0,3759715104 mm (well
now, there you are!)
The French influence was not world-wide. Many attempts were
made to have a British / American agreement on the subject (Bruce's
mathematical system on precise geometric progression, etc).
It would take till 1886 when Nelson C. Hawks came up with a standard
fairly similar to Fournier's. There was of course a problem with
it not fitting to Imperial Inches nor to US inches (these two
having legal differences to fight for). The succesfull type founders
in America came with a 83 Johnson Pica's to equal 35 cm. Since
the Johnson Pica was (in the end) somewhat undecided for (and
with variations all over the place) the Americans decided on:
1 pica to equal 4.233 mm, and 1 point to equal 0,3527 mm
The EU standardized the didot point in 1973 as 0,375 mm, something
the Germans call 'metric' and therefor 'ein typographischer Punkt',
opposed to Fournier points and Didot points - and in fact all
the other ones that may fill your old cases with led type face.
When you hear a printer's certainties you would not have the
stomach to begin an argument on how precise he would like to
All this may bring an awareness about why occasionally designs
from a Dutch artist's workshop to a Malaisian computerized book
producer, or indeed from one computer to a printer's office with
another computer 'just isn't what one expected'.
Well we are talking aesthetics, so where is the problem.
When printing, it would be nice when all you had in your press
was the same height - the press being fairly strong and such,
so anything too high might be crushed, and anything lower might
be not printed at all.
In order to have that fixed your press has a certain 'standard'
In all the years we are printing now this standard height depends
on the country your press is from.
This is all 'standard' as related to the height of lead that
is under your type:
Dutch height = Hollandse hoogte is 24,85 mm
in England that is 23,32
in France 23,55
in Germany 23,56
Practise has learned me that even the clever presses with adjustable
base, as I encountered in Germany, just do not have the flexibility
to 'do' the Hollandse Hoogte; it prints the fine Dutch Egmont
every bit 'podgruba' (as a Polish printer would call 'bold').