Bank-notes are printed upon paper composed of linen, the qualify of
which is not always the same, and it varies in thickness. Therefore,
the paper is not always a sure test, but it is important. The
manufacture of this paper is a profound secret, as carefully kept as
the combinations to the great vaults where the government's millions
lie awaiting further river and harbor bills. It is made only at
the Dalton mill, which dates back almost to colonial days. What its
combinations are nobody knows except those intimately connected with
its manufacture. The secret of the paper-making is jealously guarded,
as is also the paper itself. From the moment it is made until it gets
into the treasury vaults it is carefully guarded. It goes there in
small iron safes, the sheets carefully counted, and all precautions
against its loss being taken both by the government officials and by
the express companies which carry it.