Historical Painting Techniques, Materials, and Studio Practice

Abstract

The problems of interpretation of
written sources on painting tech­
nique are well known. Through loss
of the technical tradition, within
which details of information were
well understood at the time of writ­
ing, technical information is ob­
scured for later generations. In
courses on historical techniques of
painting at the School of Conserva­
tion in Copenhagen, attempts at re­
constructing the kind of gesso
ground used in early Italian painting
have prompted investigation into the
actual meaning of the "giesso uolter­
iano" mentioned by Cennino Cen­
nini in his treatise. This paper exam­
ines the problem from three angles:
(1) the possible meanings of Cenni­
ni's text on this point; (2) the prepa­
ration of gesso grounds from the
possible forms of gesso resulting
from the first point (dihydrate, hemi­
hydrate, anhydrite); and (3) technical
evaluation of the reconstructions and
comparison with the results of scien­
tific examination of grounds in early
Italian painting.

58

Questions about Medieval Gesso Grounds

Beate Federspiel

Konservators Skolen

Danske Kunst Akademie

Esplanaden 34

1263 Kopenhagen-K

Denmark

Introduction

The problems in interpreting written sources on painting techniques are well

known. Besides the paintings themselves, the written sources are the only

testimony of materials and techniques used in fo rmer times. Advanced meth­

ods of scientific analysis employed in the examination of paintings do not

always answer questions about materials and techniques. And the written

sources do not always provide easy access to painting techniques. Time has

obscured the comprehension of the texts. The pure linguistic translation of a

written source is often far from sufficient, but may be greatly aided by re­

constructing the technical details described and comparing the results of the

scientific analyses.

Understanding Cennini's text

During the courses in historical techniques of painting at the School of Con­

servation in Copenhagen, it was increasingly dissatisfying fo r the author and

others to reconstruct the gesso grounds as described by Cennino Cennini,

and it was eventually necessary to scrutinize his text concerning grounds.

Merely reading Cennini's instructions in the English translation by D. V

Thompson in 1933 was not sufficient; it was obvious that things were not as

easy as they may have seemed (1). Not that Cennini is imprecise in his in­

structions on this point; he is more thorough in his instructions on ground

than in his description of paint application. But how can certain important

passages be interpreted 600 years later?

The original manuscript by Cennini being lost, the question of which sur­

viving copy to use as a source remains, of course, a central one. That aspect

will not be addressed in this article; the source used here is Lindberg's Swedish

version of Cennini's Codex Laurentianus. Lindberg's translation shows semantic

details, absent in previous translations, that are important fo r the understand­

ing of decisive technical details (2).

In Chapter CXV of his treatise, fo r example, Cennini describes the prepa­

ration of the ground fo r painting on panel. Painting in the Middle Ages

included gilding. Gilding was the main reason fo r the great efforts invested

in creating a perfe ct ground. Gypsum was the material used in the prepara­

tions of grounds fo r painting and gilding throughout the whole Mediterra­

nean area as far back as the first millennium B.C.E. (3). The first written

evidence of a ground fo r painting made of gypsum appears in the ninth­

century Lucca manuscript, which mentions a ground consisting of gypsum

and glue fo r gilding on wood (4). Cennini clearly distinguishes between gesso

grosso and gesso sotille; that is, a double-structured ground consisting of several

layers of a coarse ground on top of which are applied several layers of a finer

ground. In both structures, the medium is animal glue (5). Such grounds, with

local variations, were fo und in fo urteenth-and fifteenth-century paintings

from Florence and Siena (6).

Lindberg's translation, here translated from Swedish into English by the author

(7), diff ers in several crucial passages from the 1933 English translation by D.

V Thompson. The passage concerned is the fo llowing: The Italian text says,

"poi abbi giesso grosso cioe uolteriano che e purghato ede tamigiato amodo

di fa rina, ... " which Thompson translates as, "then take some gesso grosso,

Historical Painting Tech niques, Materials, and Studio Practice