576 
therefore, that a fimplification of the pro- 
cefs will increafe the value of this inven- 
tion, which is. certainly one that, promifes 
to be of ccnfiderable advantage to the 
public. 
a eel 
MR. RANDOM BESENGER for TRANSPA- 
RENT PAINTING 07 SILK. 
A PatTeEnT has been granted to Mr. 
RaNDoM-BEsENGER (now RanDoM and 
/STAINBANK, of Old Bond Street, London) 
for dn improvement in the method of tran- 
{parent painting upon filk, linen, or cotton. 
The method cf making thele tran{pa- 
rencies is the following. The dark parts 
of the piéture are engraved on a copper- 
plate, which is then warmed over a 58 
coal fire, laid over with Frankfort black, 
the furface cleared, and upon the plate is 
placed the filk or linen to be painted. A 
Sheet of paper is laid over the back of the . 
filk, as the colour penetrates through, and 
the whole is printed in the ufual manner 
in the copper-plate prefs. The light parts 
of the picture are then well wathed on 
each fide witha ftrong {olution of ifinglafs, 
in water, and when thoroughly dry, the 
colours are laid on with the brufh. Thefe 
fhould be the cleareft and brighteft oil-co- 
‘ours. To compleat the whole, the bright 
parts may be.covered with a clear oil 
varnifh, and the piéture is finifhed, and is 
either put in a frame or mounted on {pring 
rollers. 
EE 
MR. WM. POCOCK j07 @ MACHINE for 
MOVING HEAVY BODIES. 
A Parent has been granted to Mr. 
Witiam Pocock, of Leyton, in Effex, 
carpenter, for a machine for raifing, low- 
ering and moving heavy bodies. 
This machine confilts of a long iron 
Spindle revolving on its axis, and turned 
by a winch at each extremity. The fpin- 
dle is cafed with a {trong male {crew or 
worm, the upper part of which is a right- 
hand {crew, and the lower a left-hand, or 
<aice verfa, which meet in the centre. 
‘The fpindle with its {crew which form 
oue long cylindrical piece is firmly fixed in 
an oblong immoveable frame, which in- 
clofes it on each fide, and on the frame are 
placed two moveable blocks, which lide 
up and down the frame, and alfo are cut 
in with a female fcrew, the one right- 
handea, the other left-handed, which ft 
the two male fcrews of the {pindle. 
chain or rope is fixed to the moveable 
blocks,’ and by turning the winch ‘of the 
{pindle, the motions produced, which may 
be direGed by pullies as ufualy 
\ 
is 
New Patents lately enrolled. 
MR. CHARLES TENNANT for PREPARING 
the OXYGENATED MURIATES Of LIME, 
Beczoth 
A Parent has been granted to Mr, 
CuHaRLes TENNANT, of Darnley, near 
Glalgow, bleacher, for preparing the 
oxygenated muriates of lime, barytes, 
ftrontites, or magnefia, in a dry and pow- 
dery form, or in the ftate of pafte; to 
be applied to the purpofes of bleaching, 
In a former number we gave an account 
of the patent which the fame inventor ob- 
tained for preparing thefe oxygenated mu- 
riatic falts in a liquid form, the prefent is 
an alteration in the procefs, and in fome 
degree. an improvement. It is efle&ted 
merely by expofing lumps or pieces .of 
any fize of thele earths, in clofe veffels, to 
the oxygenated marine acid in vapour; 
and by the mere contact of thefe fubftances 
they willunite, and great part of the earth 
will thus be rendered foluble in water, and 
may be applied to the purpofes of bleach- 
ing. The improvement gained by the 
former invention, of fubftituting a cheap 
earth inftead of an alkali, as a bafis for 
detaining this volatile acid, was very con- 
fiderable; and the eafe with which this 
falt may now be prepared in the dry way, 
and its convenience for carriage, will pro- 
bably be found a great faving both to the 
preparer of this article, and the manufac- 
turer. 
a 
MESSRS. DARBY, and. NICHOLS for @ 
PORTABLE OVEN. 
A PatenT has been granted to Mefirs. 
Ropert Darsy and Morcan Ni- 
CHOLS, of the city of Bath, for a port- 
able oven. 
This invention, which is very fimple, 
is intended to be applied to any circular 
upright flue, through which heated air 
will pafs, and may, therefore, occafionally 
prove a faving of fuel. It confifts of a 
tinned iron circular box, compofed of an 
upper piece that lets down upon a flat bot- 
tom plate, which forms the oven, and is 
furmfhed with a moveable ftand for fmall 
articles of paftry. ‘The box is loofely en- 
clofed in an outer cafe of the fame mate- 
rials, and between the two there is a {pace 
fufficient for the paflage of the heated air 
which pafles in at a circular epening at the 
bottom of the outer cafes, and after being 
diffufed on every fide around the oven, is 
again collected in a fmall flue at the top 
ot the cafe and carried off. ‘To prevent 
the unequal action of the heated air, there 
is a falie bottom between the oven and 
the outer cafe, which in fome degree 
checks the violence of the heat as it enters 
the oven. 
THEATRICAL 
[July 1, 
