205 
found in the ruins of Herculaneum. 
iron ; and it would seem from these circumstances, as well 
as from the omission of any mention of such a substance by 
Pliny, that the Romans, up to his period, never used the ink 
of galls and iron for writing : and it is very probable, that the 
adoption of this ink, and the use of parchment, took place at 
the same time. For the ink composed of charcoal andsolution 
of glue can scarcely be made to adhere to skin ; whereas the 
free acid of the chemical ink partly dissolves the gelatine of 
the MSS., and the whole substance adheres as a mordant ; and 
in some old parchments, the ink of which must have contained 
much free acid, the letters have, as it were, eaten through the 
skin, the effect being always most violent on the side of the 
parchment containing no animal oil. 
The earliest MSS. probably in existence on parchment, are 
those codices rescripti, discovered by Monsignore Mai, in the 
libraries of Milan and Rome. Through his politeness I have 
examined these MSS., particularly that containing some of 
the books of Cicero de Republica, and which he refers to the 
second or third century. From the form of the columns, it 
is very probable that they were copied from a papyrus. The 
vegetable matter which rendered the oxide of iron black is 
entirely destroyed, but the peroxide of iron remains ; and 
where it is not covered by the modern MSS., the form of 
the letter is sufficiently distinct. Monsignore Mai uses 
solution of galls for reviving the blackness. I have tried 
several substances for restoring colour to the letters in an- 
cient MSS. The triple prussiate of potash, used in the man- 
ner recommended by the late Sir Charles Blagden, with 
the alternation of acid, I have found successful ; but by mak- 
ing a weak solution of it with a small quantity of muriatic 
acid, and by applying them to the letters in their state of 
