478 Paper at the International Exhibition. [October, 
represented, to the surface of the fine wire gauze, of which 
the hand mould, or machine dandy roller, is constructed. 
To produce a line water-mark of any autograph or crest, 
the pattern or device must first be engraved on some yielding 
surface, from which an electrotype in copper is afterwards 
taken in the usual manner, thus producing the device in 
relief. ‘This is then affixed to the surface of the wire gauze 
of the mould, and produces a corresponding impression on 
the paper. Supposing perfect identity to be essential, as in 
the case of a bank note, the device is first engraved on a 
steel die, those parts which are intended to give greater 
effect in the paper having to be cut deepest. The die is 
then hardened and properly prepared in the usual manner, ~ 
and an impression transferred from it on to a plate of sheet- 
brass by being placed under a steam hammer or other 
stamping apparatus. ‘This being done, the die, with the 
mould plate in it, is next taken to a perforating or cutting 
machine, where the portion of the mould plate projecting 
above the face of the die is removed, whilst the portion 
embedded in the engraved design is left untouched. The 
latter is subsequently taken from the interstices of the die 
and placed ina frame upon a backing of fine wire cloth, 
and so forms a mould for the manufacture of paper of any 
pattern that may be desired. 
Light and shade are occasioned by a very similar process, 
but one which requires more care, and is consequently some- 
what more tedious. Inthe former case the pulp is distributed 
equally throughout the entire surface of the wire forming the 
mould, whereas, to produce the effects of light and shade, 
means have to be adopted for increasing, to a very great nicety, 
the thickness or distribution of the pulp, and at the same 
time to make provision for the water to drain away. This 
has been accomplished by first taking an electrotype of the 
raised surface of any model or design; and again, from that, 
forming in a similar manner a matrix or mould, both of which 
are subsequently mounted upon lead or gutta-percha, in order 
that they may withstand the pressure which is required to 
be put upon them in giving impression to a sheet of very 
fine copper wire gauze, which, in the form of a mould, and 
in the hands of the vat-man, suffices ultimately to produce 
those beautiful transparent effects in paper pulp. 
At the Exhibition there is a large display of water-marked 
papers, consisting principally, so far as England is con- 
cerned, of specimens of English and. Indian bank-notes; 
whilst the Imperial State Paper Establishment of St. 
Petersburg exhibits a large collection, including landscapes, 
