I. 6
ORIGINAL OR COPY?
I.6.1
SOME TECHNICAL OBSERVATIONS
That the Plan of St. Gall is a "copy" rather than an
"original" must be inferred not only from the fact that its
maker refers to it as exemplata, i.e., "transcribed" or
"copied," but also from a variety of observations of a
technical nature, on which I have reported in a previous
study.[105]
A careful examination of the particulars of the
design of the Plan shows that it was traced, like a modern
"overlay," on pieces of parchment that were superimposed
upon a prototype plan. This is revealed by the following
facts:
1. The Plan does not show any underdrawing, as
would be inevitable in a layout of this complexity if it were
an original design.
2. The Plan exhibits in several places angular distortions
in the alignment of rectangular structures which are
characteristic of the displacement that occurs in tracing if
in the course of work the overlay inadvertently shifts a
few degrees from its initial alignment with the original and
this shift is not immediately corrected.
3. The drawing is full of minor inaccuracies and inconsistencies
that appear to be incompatible with the
exacting calculations prerequisite to the development of an
architectural drawing of this complexity; and it is rendered
in a fluid style not apt to be found in the work of a man
who went through the developmental labor of this demanding
task.
In what follows I shall elaborate on these observations.
ABSENCE OF UNDERDRAWING
In figure 6, I have reproduced a detail of a well-known
architectural drawing of the thirteenth century which
renders the ground floor of the southern tower of Cologne
Cathedral.[106]
This design, which is a typical example of its
kind, shows how in laying out his plan a medieval architect
avails himself of an elaborate framework of auxiliary construction
lines and reference points which he presses into
the parchment with a fine stylus or silverpoint before
committing his drawing to ink. This constructional reference
work guides his eye as the drawing is being executed
and remains visible as an underdrawing, in the form of
thin grooves and fine prickings,[107]
in those portions of the
design which are not covered by ink in the final stage of the
work.[108]
In contrast to this, on the entire Plan of St. Gall there is
not a single line of this type to be found.[109]
The absence of
such auxiliary construction work is most conspicuous in
areas where buildings of equal width are grouped in single
and double rows, or in the interior of buildings whose
layout is so complex that it could not have been drawn
without a linear frame of reference. This can be illustrated
by some typical examples.
ABSENCE OF GUIDING CONSTRUCTION LINES
IN THE ALIGNMENT OF BUILDINGS
Reproduced in figure 7 is a portion of the building site
to the north of the Church, showing (from top to bottom)
the western end of the Outer School, the House for Distinguished
Guests, and the Kitchen, Bake, and Brew
House for Distinguished Guests. Examination of the open
spaces between these structures shows that the parchment
here has never been touched by a stylus. This had noticeable
consequences for the style of these drawings: the walls
that form the outer boundaries of these houses do not stay
"in line," most drastically so in the case of the Kitchen,
Bake, and Brew House, whose southern gable wall slants
away from its proper alignment by an angle of two degrees.
If the parchment surface had been provided with guiding
construction lines, the draftsman's hand could never have
slipped away from its regular course as far as it did when
drawing the southern walls of the Kitchen and Bake House,
converting a building that was of rectangular shape into a
trapezoid structure.
An even more flagrant case of the divergence of lines
meant to run parallel to one another is to be found on the
opposite side of the Plan in the alignment of the three
buildings that contain the Mill, the Mortar, and the Drying
Kiln (fig. 8). This kind of linear aberration might easily
occur in the process of copying when the translucency of
the skin on which the Plan was being traced was temporarily
marred by changing light conditions, but would be unlikely
to occur on an original where the quill of the draftsman
followed the grooves of a constructional underdrawing.
On the Plan of St. Gall such grooves can be discovered
neither on the recto in the form of the familiar furrows nor
on the verso in the form of thin ridges. Throughout the
entire expanse of the Plan, with its total of forty separate
structures of varying size, no trace is to be discovered of
any underdrawing that would have enabled the architect
to fix the dimensions of an individual structure within the
aggregate of its superordinate building site, or the boundaries
of the individual building site within the layout of the
entire Plan. Yet it is obvious that even the most accomplished
architectural draftsman could not assemble such a
variety of different structures into an over-all design of
such complexity without the aid of a guiding underdrawing.
In the absence of underdrawing, the design can only have
been produced by tracing.
Parchment, because of its relative opacity, is not an ideal
medium for tracing; but designs can be traced directly
from one sheet of parchment to another, as may be established
easily by experimentation in any library that is
provided with scraps of medieval manuscripts.[110]
ABSENCE OF GUIDING UNDERDRAWING IN THE
INTERNAL LAYOUT OF INDIVIDUAL BUILDINGS
An examination of the procedure followed in the construction
of the internal layout of the various buildings leads us
to the same conclusions. No building illustrates this fact
more persuasively than the Monks' Dormitory.
The Dormitory of the monks (fig. 60.A) accommodates a
total of seventy-seven beds. These are arranged in a
complicated pattern, resembling the letter U along the
two side walls, and the letter H (the U-pattern of the side
walls coupled) along the center of the building. One does
not have to look twice at this complex arrangement to
realize that it is impossible to distribute seventy-seven beds
in the manner just described within an area of such small
dimensions without a carefully calculated underdrawing.
Yet intricate as this layout is, the basic frame of reference
from which it was developed was ingeniously simple. It
consisted, most likely, of a simple grid of squares of the
type that I have reconstructed in figure 60.B, making use of
a measurement that serves as a basic unit value throughout
the entire Plan. In the development of the primary design
for such a layout, which must have been worked out before
the building was inked onto the original plan, such a
square grid may have been pressed into the parchment in
full detail. As the design was transferred to the master
sheet in the final assembly, there was no need to retrace
the square grid in its entirety, but a minimum of auxiliary
co-ordinates and prickings must, nevertheless, have been
laid down to enable the draftsman to fix the width and
length of each bed and to enter it in its proper place. Yet
nowhere in the interstices between the beds, on the Plan
of St. Gall, is there the slightest trace of such auxiliary
construction work. It is omitted from the internal layout of
the buildings shown on the Plan, and absent as well from
their external alignment.
ABSENCE OF CENTER POINTS IN THE
CONSTRUCTION OF CIRCLES
To construct a circle accurately, one must firmly anchor the
center leg of the compass in the material on which the
circle is to be drawn. The point of this leg has to penetrate
deeply enough to stay in place while the outer leg strikes
the circle. This is bound to leave a mark in the parchment,
and for this reason, on all medieval architectural drawings
on which circles have been drawn with the aid of a compass,
there is always a clearly visible depression or minute hole
in the skin, which reveals the point from which the circle
was struck. I refer once again to the drawing of the southwestern
tower of Cologne Cathedral as a typical case. It
contains two circular installations, a spiral stairwell built
into the masonry of the southwestern corner pier (fig. 9)
and a circular opening in the vault of one of the two inner
bays of the tower (the latter not reproduced here). In both
instances the hole that the center leg of the compass left in
the parchment as the circle was struck appears as a small
but clearly perceptible mark.
For purposes of comparison, five circular installations
shown on the Plan of St. Gall are reproduced in figures
10-13. Figures 10.A-B are the ambo and the baptismal font
in the nave of the church; figures 11.A-B are the two
circular towers that flank the Church to the west. Figure 12
is the enclosure for the hens to the south of the House of
the Fowlkeepers. No trace of the center point is found in
any of these drawings. Furthermore, these circles are too
inaccurate to have been constructed with the aid of a
compass. A circle drawn by compass forms a continuous
line of equal thickness, all points of which are equidistant
from the center point, as is well illustrated by the circle
that forms the outer boundary of the stairwell of Cologne
Cathedral. The circles reproduced in figures 12-13, on
the other hand, are drawn in successive motions of the
rotating hand, the beginning and end of which can still
be identified in many cases. Thus, for instance, close
inspection of the Plan of St. Gall shows that the outer
circle of the Henhouse (fig. 12) was drawn in five separate
strokes. The circle must have been started at the top
with a leftward motion and continued counter-clockwise
in four successive strokes, as I have indicated in figure 13.
As the draftsman passed through this course, he must
have rotated the two skins on which he worked in a
clockwise motion, a procedure which he repeated when
he entered the large explanatory title enclosed by the
circle that identifies this structure as the Henhouse. As he
approached the close of the circle, the draftsman discovered
that his terminal stroke was not in alignment with his
opening stroke, corrected this discrepancy with an additional
stroke which ran parallel to the first, but about 1 mm.
farther out.
While the circles are neither continuous nor accurate
enough to have been drawn by compass, they are far too
accurate to have been drawn without auxiliary construction
lines. As no such lines are to be discovered, we are once
more left with no alternative but to assume that the circles
were traced directly from an underlying original.
ANGULAR DISTORTIONS CAUSED
BY A SHIFT IN THE RELATIVE POSITION OF
ORIGINAL AND OVERLAY
My second argument in support of the contention that the
Plan of St. Gall is not an original rests on the observation
that in several areas the drawing exhibits angular distortions
that owe their origin to a shift in the alignment of original
and overlay. This observation is of crucial importance not
only for the question of originality but also because it gives
us a clue for establishing the sequence in which the buildings
were traced. We shall analyze this phenomenon in
detail in a subsequent chapter.[112]
For the present discussion,
suffice it to stress that we are faced here with a type of
linear deflection caused in the process of tracing when an
inadvertent shift between original and overlay is not
immediately detected and corrected. These deflections are
unlikely to occur on an original, as the underdrawing
would contain each individual building within the area
assigned to it, and would prevent the parallels from running
askew. The author of the Plan of St. Gall was able to
dispense with an elaborate system of auxiliary reference
lines, since for him the original itself performed the
function of the underdrawing. But as it was delineated on
a different surface, his drawing was subject to displacement
in relation to the original.
INCOMPATIBILITY BETWEEN THE FLUID
EXECUTION OF THE DRAWING AND
THE PRECISE DRAFTSMANSHIP REQUIRED IN THE
DEVELOPMENT OF THE ORIGINAL SCHEME
My last and final argument in favor of the proposition that
the Plan of St. Gall is not the original version of the scheme
is based on the observation of a profound discrepancy
between the fluid style of the drawing and the extraordinary
precision of construction that must have been employed in
the development of the original scheme—not only as the
dimensions of each individual building were established,
but also in the even more complicated task of fitting the
aggregate of structures into a coherent and scale-consistent
whole. No single line of the Plan has the mark of having
been drawn by rule or compass, as is the case with all the
principal lines of the pier and the tower of Cologne Cathedral (figs. 6 and 9). The draftsman of the Plan of St. Gall
rendered his lines with a broad quill in firm and fluent
strokes, the ease of which reveals the self-assurance of an
experienced hand; but being drawn without the aid of
supporting instruments, his rendering abounds with
inaccuracies and inconsistencies that are incompatible
with the precise draftsmanship required in the development
of the original scheme. About the nature of the latter more
will be said below. The observations presented here admit
of no other explanation than that the Plan of St. Gall is
a copy that was traced on sheets of parchment superimposed
upon a prototype plan. This raises the question
of the nature and origin of the prototype plan.
[ILLUSTRATION]
12. PLAN OF ST. GALL. HENHOUSE
