Earthen Vases known by the name of Etruscan. 5$ 
lava has formed the basis of the coating of vases, its natural fu- 
sion having been strongly assisted by the addition of seme saline 
substance * *. Vauquelin was the first who discovered that the 
black paint was carbonaceous, and he is at the same time of opi- 
nion, that it was prepared from graphite or anthracite *f*» 
From experiments made with the view of investigating this 
matter, I too have found that the black coating of vases con- 
sists of a combustible substance, either carbonaceous or bitumi- 
nous ; with this determination, the above-mentioned experiments 
also agree, inasmuch as it is not dissolved by acids. On throw- 
ing particles of the black coating into nitre fused in a platina 
cup, they burned by sparkling, and were quickly consumed. 
By this experiment, the singular phenomenon, that a coating so 
thin should have presented its colour and lustre for so long a 
period, is satisfactorily explained. 
The question regarding the substance from which this black 
coating has been derived, is more difficult of solution. I can- 
not give my assent to the opinion of the celebrated Vauquelin 
mentioned above. It is shown by the colour and lustre of the 
paint, that it could not have been prepared from graphite , a 
substance which has more of the colour of iron, and a metallic 
lustre. The quality which it possesses of fusing with nitre, as 
above related, is also against its derivation from graphite and 
anthracite. If we suppose the paint to have been laid on with 
a pencil, it may be inferred that its substance had been fluid of 
itself, or had been reduced to a state of fluidity by means of 
some other substance. As the appearance of the coating of 
vases proves its fusion, it may be concluded, that the matter 
was either fusible of itself, or had been rendered so by intermix- 
ture with some other substance. Nor does it seem improbable, 
that, in order to form this coating, a substance was applied, 
which either occurred in the different countries in which those 
vases were manufactured, or was easily procured by commerce. 
I instituted various experiments, with the view of determining 
this substance, which entirely failed, because I followed the com- 
mon opinion, that the black coating of the antique vases was 
* Mem. de l’lnst. 1808, p. 234*. 
*f* Milling Peint. des Vases Ant. p. 7, No. 47. 
