the chief restorer, Professor Haysinek, and Mr. Sochor, the head of the
technical department, who had practiced that special method of cradling
since 1930, the reinforcement of wooden supports was accomplished in a
quite traditional way with the use offlat cradle systems. It is quite remark-
able that partial transfers were executed on some Rubens’s panel paintings:
paintings situated on portions of the panels whose grain orientation was
not parallel to the rest of the support were transferred to new supports of
the same wood species with parallel grain; they were then inserted back
into the overall ensemble (Keyselitz 1960:73–75). The Vienna method is
also known as the Sochor method.
Avery concise summary about all the problems of cradling and
the reasons to avoid it was written by Straub (1963:139–64).Balsa-block systems
Straub made a major contribution by bringing to the German conservation
scene the discussion about structural panel painting conservation raised by
Richard Buck in the United States (Straub 1963:154). Several years later
Roettger published a case study about an application of the new balsa-block
system (Roettger 1967:13–17). During the following fifteen years, this
method was frequently used in cases where formerly thinned panels were
reinforced after the removal of rigid lattices or cradles. Some interesting
case studies are in the archives of the Schweizerisches Institut für
Kunstwissenschaft, among them Holbein’sSolothurn Madonna(the treat-
ment ofwhich will be described in detail below). Normally the balsa blocks,
cut longitudinally into little bricks, were applied as an initial layer along the
grain of the panel. Then a second layer of blocks was set across the grain,
or again along the grain. The glue was usually wax cement with filler.
Christoph von Imhoffproposed the application ofquadratic balsa blocks
affixed diagonally in relation to the grain of the support with the use of
Master Model Paste (a putty ofsawdust and epoxy resin, also marketed
under the trade name Araldite) as glue; the blocks also served as an equal-
izer for the support’s surface (von Imhoff1973:94).Transfer to a new support
Wooden panel paintings have been transferred to new supports for many
years. The significance of such a treatment in relation to the original sub-
stance ofa panel painting, comprising a support and its paint layer, was
not yet recognized at the beginning of this century (Krattner 1910:150).Total transfer
In comparison to partial transfers of thinned wooden supports, total
transfers were not frequently done in Germany. Total transfer was often
described in early restoration texts. The most extensive coverage of the
subject can be found in Hertel’s 1853 translation of Hacquin’s work on the
Madonna di Foligno. Köster clearly stated that the paint layer should be con-
trolled and that blisters should be consolidated before the joiner’s work
begins (Köster 1827:16). Welsch described how the joiner is involved in the
transfer work (Welsch 1834:66).
Transfer from wood to wood. Until the end of the nineteenth
century, wooden panels were used as new supports for the transferred
paintings. Since the only technical possibility was to transfer the painting
to another wooden panel, the transfer of paintings did not occur oftenH P P C A, G, S 219