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preceded by a period of development of unknown length, when all designs were guided
only by trial and error, and there must have been many early failures (a state of affairs not
unknown in the present day).
The people of a particular region, which might be as small as a town or as large as a
country, are likely to be at least somewhat chauvinistic about their ancient artifacts. This
is certainly true of windmills, with respect to who had the earliest, the most, the largest,
the best built, the most aesthetically pleasing, and so on. The palm would seem to go to
Holland for the greatest number per unit of land area and for the widest utilization. The
average density of windmills in Holland at their peak was perhaps three times that of
England. But then, what country could compete with between 800 and 1,000 windmills in
a few square miles, as at Zaandam, a suburb of Amsterdam? From the seventeenth century
onward, it was a highly industrialized town that used windmills for power as we use electric
motors. Or what country had the equal of the 19 large drainage windmills along a mile or
so of the Kinderdijk in South Holland?
The windmill is recognized everywhere as a logo of Holland, along with the tulip and
the young lady in the traditional costume and white cap. But there the unanimity of opinion
ends, and there is much spirited competition to identify the earliest record of the European
horizontal-axis windmill and the “best developed” mill. The former is subject to the degree
of proof required by the exponent or arbiter. As to the latter, we have no clear winner, and
chauvinism could reach its height in attempts to ind one.
The Post-Mill Design
The psalter picture of 1270 (Figure 1-6), referred to earlier as the irst know illustration
in a topic of a European windmill, shows a mill with a long handle to turn it into the wind;
the whole body is mounted on a central post
supported by offset struts to the ground.
This is known as a
post mill
,
and it is the
simplest type of horizontal-axis windmill.
There are a number of drawings and sketch-
es from the fourteenth and early ifteenth
centuries, all showing crude representations,
particularly with respect to perspective.
Figure 1-7, depicting a mill of 1430, is given
here because it attempts to show a cross sec-
tion of the interior and the exterior [Usher
1954]. It is very simple and not to scale, but
it does show the cog-and-ring gear, the feed
of grain to the stones, and the pole for turn-
ing the whole structure on the post, which
itself is not shown clearly. Note that the
pole seems to be drawn as an afterthought,
with a peculiar placement; it was normally
on the back of the mill for safety and to help
in balancing the weight of the sails.
We can only speculate on the develop-
ment of post mills for some four centuries
from their known inception in the middle of
the twelfth century, because descriptions and
drawings having any signiicant detail have
not come to light from that period. It would
Figure 1-7. A crude sketch of the com-
ponents of a post mill, c. 1430.
The pole
at the lower left is presumably for winding
the mill [Usher 1954].
(Reprinted by
permission of Harvard University Press)
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