470 Paper at the International Exlibition. [Oétober, 
Messrs. B. Donkin and Co., of London, and by Messrs. 
G. Bertram and Co., of Edinburgh. 
The pulp, when sufficiently ground, descends into a 
reservoir, in which it is kept constantly agitated in water. 
From this reservoir the pulp passes into a trough, where it 
is strained by means of a sieve, or ‘‘knotter,’’ as it is called, 
the under part of which communicates with an exhaust 
pump in order to facilitate the passage of the pulp through 
the fine meshes of the “‘knotter.”” Passing from the strainer, 
the pulp is next distributed equally throughout the entire 
width of the machine, and is afterwards allowed to flow 
over a lip or ledge in a regular and even stream, whence 
it is received by the upper surface of an endless woven 
wire band, upon which the first process of manufacture 
takes place. This wire band, as it travels forward, has also 
a gentle vibratory motion given to it in order to assist the 
pulp to spread evenly over its surface, and to facilitate the 
separation of the water, which latter is also further aided 
by the action of a suction pump beneath, and thus the pulp 
solidifies as it advances. The width of the paper is regulated 
by deckle or boundary straps, which travel at the same rate 
as the wire gauze, and so limit the spread of the pulp. 
The partially solidified pulp now passes under the 
“‘dandy”’ roller, which is employed to give any impression 
to the paper that may be required, and in forming what is 
called the ‘“‘ watermark,” to which we shall presently refer 
more fully. The paper ‘then passes under two “‘ couching ” 
rollers, which are simply wooden rollers covered with felt. 
Merging from these the paper is received from the wire 
gauze by a continuous felt, which conducts it through two 
pairs of pressing rollers, and afterwards to the drying 
cylinders, which are heated internally with steam. The 
paper, after passing over these cylinders, is finally wound 
upon areel. For the finer sorts of paper, and especially 
for writing paper, a subsequent process of sizing must be 
undergone, which in most cases is effected continuously 
with the manufacture of the paper, and before it is finally 
wound. 
To convey some idea of the number of substances which 
have been really tried for paper making, it may be stated 
that in the library of the British Museum may be seen a 
book, printed in low Dutch, containing upwards of sixty 
specimens of paper, made of different materials, the result 
of one man’s experiments alone, so far back as the year 
1772. Infact, almost every species of tough fibrous vegetable, 
and even animal substance, has at one time or another been 
