sh E34 I 
[Aug. 1, 
NEW PATENTS AND MECHANICAL INVENTIONS: 
— 
To Tuomas Attwoon, of Birmingham, 
Warwick, Banker, for a Communica- 
tion made to ‘him by a Person, residing 
abroad, of certain Improvements mm 
the making of Cylinders for the 
Printing of Cottons, Calicos, and other 
Ariicles.—June 9; 18238. . 
HIS improvement is to solder a 
cylinder of ‘copper, or other me- 
tal; or alloys of metal, upon a cylinder 
of iron; which is to he done by any of 
the usual modes of suldeiing metals 
together. Cylinders may be thus 
produced, with surfaccs suited for 
engraving devices upon,, for printing 
ealicos, &e.: the surface only being of 
eopper, while the internal part of the 
eylinder is composed of a cheaper and 
stronger material. 
This contrivance allows of the sub- 
ject, on the face of the copper, being 
removed, by turning and polishing, 
without reducing the cylinders so as 
to affect their strength, and even per- 
mits the whole of the copper to be 
taken off, and new copper attached to 
the sanie iren cylinders, at a trifling 
expense, compared to the entire cost 
of new copper cylinders. — Louden 
Journ. of Arts, Se. 
—f—— 
To: Tuomas’ Hopper, of Reading, 
Berks, esq. for his Tuteition of certain 
Unmprovements in the Manufactire of 
Silk Hats-Noy. 2, 1823. 
The proposed object of this patent is 
to render the materials of which silk 
hats are made completely water-proof. 
The woollen substance which forms 
the basis. is first to be boiled in a so- 
Jution of the supersulphate of alumine 
and potass (common alum) for two 
hours; th; the proportion of two or 
three pounds of alum to a gallon of 
water. Tt is then to be taken’ out, 
well rinsed in clear waiter and wrung, 
and immediately dipped in’ a solu- 
tion: of isinglass\ or glue, of: variable 
strength, at a boiling heat; and put on 
a frame to dry and give it a shape. - 
The eloth thas prepared, and before 
it becomes: quite dry, may be again 
immersed ini a’ strong solution of the 
acétate or tartrate of alumine, or su- 
persulpliate, and allowed to remain in 
the Tiquor for afew hours ; it may then 
be ritsed and dried as before. - The 
lignor must not be hot. 
A third method is to dip the cloth 
(previously alumed) in a solution of 
gelatine and. one of the nigenibilin 
salts added together; when wrung, 
immerse. it once or twice inan al- 
kaline lixiviam; afterwards: let it be 
dried.. By these ‘processes, the ge- 
latine is set or fixed in what may be 
termed the first, second, and third, 
degree. In the last process, a double 
chemical change is effected: the acid 
of the aluiminous salt leaves it, and 
attaches itself to the alkali, while ‘its 
base, the alumine, combines with the 
gelatine, and renders it insoluble vin 
water, and together with it Remaion 
affixed to the cloth. 
Various important advantages ‘aps 
pear to be derived from the alumining 
process; it effectually removes \ tho 
crease from the wool, by whieh, eon-= 
joined with its strong aflinity, for the 
cloth and, gelatine, between -which 
there exists but litde naturally, it acts 
as a powerful intermediumyin fixing 
the latter, enables it to resist the: ae-— 
tion of water, from the absorption of 
which, when used in its simple state} 
and. consequent increase of volume; 
arises one of the principal causes of: 
the disjunction and fallin to powdér 
of the resinous gums. It prevents the 
cloth from shrinking in any sensible 
degree iwhen subsequently, wetted; 
facilitates the adhesion of the ¢urtis 
with the wool, and serves to equipoisé 
those materials bei are fusible’ BY : 
heat. 
The resinous gums may now we ‘aps 
plicd in the same manner. as at présent 
practised, or they may be used in tlie 
humid way, dissolved m a spirituous 
menstruum, with: a) proportion .of 
Venice turpentine. {tis usual to mix 
a third or fourth part of resin.or san 
daric With the lac; but tlie: mastic is 
preferable, not curling. up inocoodling 
like the sandaric, and possessing:more 
tenacity than» either. ‘It contains a 
stbstanee; amounting ‘to nearly: a 
fifth, greatly analogous to caoutchones 
Caoutchoue or elastic gum, dissolved: 
in’ rectified oil of turpentine, and rene 
dered: drying by pure alumine;:or by 
washed, zther, or, which is more eco+ 
noshical, as:much acetate ofialumineag 
it will absorb : they should: be: rubbed 
together. It is, however, only. intended 
as a partial application. .2» #0 
. Between the resinous guins: and'the 
varnish,! an intervening substance, not 
fusible by heat, is necessary, to pre- 
vent 
