50 
only the linen, but the paper manufacture 
has been effentially benefited hereby. 
Formerly writing paper could be made 
of unprinted linen alone, but by means 
of the procefs of Mr. Bertholet even 
printed linen may be made into the fineft 
and whiteft paper. The prefent patent 
is the laft that we fhall detail on this 
fubje&t, except in cafe of fome effential 
improvement in the procefs or inftru- 
ment made ufe of. It was granted to 
Mr. Erias CARPENTER of Bermond- 
fey, Surrey, and is entitled a Method of 
Bleaching Paper in tbe Water Leaf, and 
fixing it without drying. 
In the preparation of the pulp, the 
eoarfer rags are to be macerated for two 
or three days in a cauftic alcaline ley, 
and wrought into fheets of paper, in the 
wiual way; a ftrong wooden box or 
trough is then to be procured, of a fize 
proportioned to that of the paper, lined 
on the infide with white paint, and fur- 
_hifhed with feveral ftages of crofs bars 
of glafs: the bottom of the box is to 
be covered with a ftratum about one 
inch deep of cauftic ley, and the paper 
laid by quarter-reams, or lefs, acrofs the 
glafs bar.. A hole muft be made in the 
box to admit the beak of an earthen- 
ware retort, into which muft be put 
manganefe and fea falt, in powder, ful- 
phuric acid, and an equal quantity of 
water impregnated with the fteams of 
burning fulphur (fulphureous acid).— 
The cover of the box is to be made air- 
tight by luting or flips of paper dipped 
in pafte. The apparatus being thus pres 
pared, the belly of the retort is to be 
plunged in water, kept boiling, and in 
a fhort time the oxymuriatic acid gas 
will be driven into the box, will pene- 
trate the paper, and render it of a 
dazzling whitenefs, while the alcaline 
ley at the bottom will, by gradually ab- 
forbing it, prevent its becoming fo con- 
centrated as to deftroy or injure the tex- 
ture of the paper. From three to four 
pounds of fylphuric acid will fuffice for 
pne hundred weight of paper, and. the 
operation will be completed in. about 
eight hours. The fheets as they are 
taken out of the box are to be fized with. 
the following mixture : 
To xewt. of clippings of skin add 
New Patents—Mr. Wedgwood’ s. 
f Jan. 
r4 lb. of allum, 7 of calcined vitriol, 
and 1 lb. of gui arabic, witha fufficient 
quantity of water to fize so reams of 
fools-cap. * | 
The fame method will ferve equally 
well to clean engravings or printing, for 
though the oxymuriatic acid difcharges 
all ftains, dirt, &c. yet it is incapable of 
acting on printers’ ink, 

MR. WEDGWOOD's, FOR MAKING OF 
j GLASS. ids 
IN November, 1796, a patent was 
granted to RatpH WEDGwooD, of 
Buriflem, Staffordthire, for anew compo- 
pofition for glafs. The two extreme 
quantities for the materials, are given 
in the following formula ; for according 
to the required hardnefs of the glafs will 
be the proportions to be made ufe of, 
From 10 to 50 lbs. of pearl-afh are to 
be diffolved in from 12 to 20 quarts of 
water ; to which are to be added from 
3 to 10 lbs. of borax, diffolved in from 
10 to so quarts of water: of Paris 
plafter, or lime, are to be added from 
40 to 100 lbs,; of flints, or any pure 
quatzy ftone, powdered, from 50 to 
100 lbs. ; of pounded barytes from 5 to 
tolbs.;and of broken china,or fine earthen- 
ware, from s0 to '1rgo lbs. (Inftead of 
this laft, from 80 to 100 lbs. of baked 
clay may be added). All thefe mate- 
rials are to be ground into a fmooth 
cream-like confilttence in the common 
mill, then eyaporated to drynefs, after- 
wards melted in a full white heat, and 
poured into water. The glafs thus pre- 
pared is ufed either by itfelf, or mixed 
with different colouring fubftances. 

MR. WEDGWOOD'S, FOR PLATING 
‘EARTHEN WARE. r 
Together with the above patent is 
enrolled one, taken out at the fame 
time by the fame perfon, for an im- 
provement in the manfaéture of earthen 
ware.. To a plate of foft unhaked cuarfe 
pottery clay, is applied on each fide a 
thin plate of china, white ware, or creams 
coloured ; the three plates are then 
united firmly to each other by. means of 
a.prefs : afterwards the mafs by rolling 
is. brought to a proper thicknefs, and 
thaped in moulds in the ufyal way. 
VARIETIES, 
