50 Prof. Hausmann on the Composition of the Ancient 
which is known by the different degrees in which the mass ab- 
sorbs water. 
It is the general opinion of all who have written on the com- 
position of antique vases, such as Grivaud * * * § , Rossi *f*, Hirt j, 
and Jorio §, that the painted vases of antiquity have been manu- 
factured in the same manner as our finer modern pottery-ware ; 
that after being first baked, the paintings have been applied, 
and the whole submitted again to a greater heat. 
From the vases themselves we cannot now learn whether they 
have been once or twice baked ; but from any investigations, 
with regard to the nature and composition of the paintings, it 
seems to me more probable that the whole have been once 
strongly baked, by which they have acquired the necessary de- 
gree of hardness and fineness, and at the same time preserved 
their porosity, and that the colours have afterwards been spread 
over them by a lesser heating. 
5. Composition of the Paintings. — In a disquisition regard- 
ing the mode in which the colours may have been applied, 
the following subjects demand investigation : — 1. The nature 
of the pigments ; 2. The mechanical mode in which they are 
laid on ; 3. The operations used after the pigments have been 
applied. 
None of the vases are overlaid with the vitreous substance 
which we call glaze , either joined with the colours, or separated 
from them. The vases which are entirely black, have no coat- 
ing different from the mass, and the lustre of the surface is pro- 
duced by the substance of the vase itself, as we shall presently 
show. Other vases are furnished with a simple black coating, 
which, however, has no resemblance to the glaze of our earthen- 
ware, but is more like varnish ||. Painted vases either show in 
certain parts a surface of baked clay, or there is a very thin, 
* Ant. Gaul, et Rom. p. 126. 
-j- Millingen , Peint. Ant. p. 5, 
£ Boettiger's Griech. Vasengemalde, Bo. 1. Heft, 3. p. 28* 
§ Sul. Met. d. Ant. nel Dipingere i Vasi, p, 19. 
|| Jorfoy who has made very accurate observations regarding the paintings of 
vases, aptly compares the black varnish to China ink ; loc, cit, p. 5. 
