that
Coster began as a xylographer and ended as a typographical printer,
and before 1472 he had manufactured and extensively used at least
seven different styles of primitive looking individual movable
cast-metal type.

According to tradition, while he was walking in a wood near Haarlem,
Coster cut some letters in the bark of a beech tree, and with them,
reversely impressed one by one on paper, he composed one or two lines
as an example for the children of his son-in-law.

Junius does not say it, but clearly implies that, in this way, Coster
came to the idea of the movability of the characters, the first step
in the invention of typography. He perceived the advantage and utility
of such insulated characters, which hitherto he had been cutting
together on one block, and so the invention of printing with
individual movable type was made.

The questions as to whether he continued to print with movable
"wooden" type, or even printed books with them, cannot be answered,
because no such books or fragments of them have come down to us.
Junius' words on this point are ambiguous, and yet, upon the
examination of the first edition of the Dutch Spiegel (of which two
copies are preserved at Haarlem) no one would deny that there are
grounds for this belief. The dancing condition of the lines and
letters make it almost impossible to think that they are impressions
from metal type. But for how long and to what extent movable wooden
type were employed, if at all, cannot be positively stated.

However, this idea of movability, and the accidental way in which it
was discovered, form together the pith of the Haarlem tradition as
told by Junius. Nothing seems more natural than that a block-printer
should cut such separate letters as Coster did on the bark of a tree
and thereupon perceive that they could be used over and over again for
a variety of words on different pages, while those which he used to
cut in a solid block only served him for one page and for one purpose.

It is equally clear from the Haarlem tradition that the art of casting
metal type was the second stage in the invention, a development or
outcome of the primary idea of "movable letters," for Junius says that
Coster "afterwards changed the beechen characters into leaden, and the
latter again into tin ones."

Theod. Bibliander, in 1548, was the first to speak of movable wooden
type and to describe them. First they cut their letters, he reports,
on wood blocks the s