found in the ruins of Herculaneum. 
*99 
gdly. An account of the experiments on Papyri, made in the Mu- 
seum at Naples. 
Only one method, and that a very simple mechanical one, 
has been adopted for unrolling the MSS. It was invented by 
Padre Piaggi, a Roman, and consists in attaching thin animal 
membrane by a solution of glue to the back of the MSS. and 
carefully elevating the layers by silk threads when, the glue 
is dry. 
In considering this method in its general application, some 
circumstances occurred to me which afforded an immediate 
improvement. A liquid solution of glue had been used, which, 
when the texture of the MSS. was loose or broken, pene- 
trated through three or four layers, and these, when the 
glue dried, separated together. To obviate this objection, I 
mixed the solution of glue with a sufficient quantity of alcohol 
to gelatinize it; and a mixture of the jelly and the fluid being 
made and applied by a camel's hair brush, a film of jelly 
remained on the exterior of the surface of the leaf, which 
attached itself to the membrane. 
The effect of the solution of glue applied in the ancient 
method, was always likewise to separate the layers, by 
expanding the imperfectly carbonized fibres. In the im- 
provement I have mentioned, the alcohol, from its greater 
lightness, penetrated farther into the papyrus, but produced 
its greatest effect immediately on the first layers. 
I adopted in some cases ether, as an agent for assisting 
the separation of the layers ; and it was always found very 
efficacious, whether it was necessary to remove a single 
