Feb. 5.] THE NEW ZEALAND GAZETTE. 393

termittently rotated and of pressure rollers mounted in a
block reciprocated relatively with the said rotary die, sub-
stantially as described. (4.) The improved apparatus for
grooving the lids or covers of sheet-metal cans or boxes,
consisting of the parts constructed and combined substan-
tially in the manner described, and operating as and for the
purposes set forth. (5.) A sheet-metal box or can the lid or
cover of which has grooves formed by means of apparatus
substantially as described, and wherein a portion of the metal
between the grooves is pressed up and has a tongue attached
to it for facilitating the tearing-out of the strip, substantially
as set forth.
(Specification, 5s. 6d. ; drawings, 1s.)

No. 15870.—15th January, 1903.—BRYAN TULLY, of Victor,
Teller, Colorado, United States of America, Inventor. Im-
provements in barrel filters.

Claims.—(1.) A filter of the class described, comprising a
rotatable barrel provided with an acid-proof lining arranged
in intimate contact with the interior of the barrel, for pre-
venting the solvent coming in contact with the barrel, and
filters formed in the body of the lining, said barrel being
apertured at the points where the filters are located, sub-
stantially as described. (2.) A filter of the class described,
comprising a rotatable barrel provided with a lead lining,
the body of the barrel being provided with outlets, and the
lining being perforated opposite said outlets, substantially as
described. (3.) A filter of the class described, comprising a
rotatable barrel provided with a lead lining, the body of the
barrel being provided with apertures and the lining being
perforated opposite said apertures, a launder arranged on
the exterior of the barrel and provided with a plurality of
branch pipes, said branch pipes at their inner ends being
fitted in said apertures and connected to the lead lining
about said perforations, substantially as described. (4.) A
filter of the class described, comprising a rotatable barrel
provided with a lead lining, the body of the barrel being
provided with apertures and the lining being perforated
opposite said apertures, a lead launder arranged on the
exterior of the barrel and provided with a plurality of le.d
branch pipes, said branch pipes at their inner ends being
fitted in said apertures and connected to the lead lining
about said perforations, substantially as described. (5.) A
filter of the class described, comprising a rotatable barrel
provided with a lead lining, a lead launder arranged on the
exterior of the barrel, a plurality of laterally projecting
branch pipes, said pipes at one end being fused to the
launder and at their ends extending through the shell or
body of the barrel and fused to the lead lining, the lead
lining being perforated at the points where the branch pipes
are connected to it, substantially as described. (6.) A filter
of the class described, comprising a rotatable barrel provided
with a lead lining, a launder arranged on the exterior of the
barrel and parallel to the longitudinal axis of the latter,
branch pipes connected at their outer ends to the launder
and extending at their inner ends through the body of the
barrel and united to the lead lining, said lead lining opposite
the inner ends of each of said branch pipes being provided
with a circular series of perforations, substantially as de-
scribed. (7.) A filter of the class described, comprising a
rotatable barrel provided with an acid-proof protective lining
in direct contact with the interior of the barrel, and filter
formed in the body of said lining, said lining being im-
pervious to the solution at all points excepting those wherein
the filters are located, substantially as described. (8.) A filter
of the class described, comprising a rotatable barrel, an acid-
proof lining fitted within said barrel and in close contact
with the interior thereof, filters formed in the body of the
lining, said barrel being apertured opposite the filters, and a
launder arranged exteriorly of the barrel and in communica-
tion with the filters, substantially as described. (9.) A filter
of the class described, comprising a rotatable cylindrical
barrel, and an acid-proof protective lining arranged in con-
tact with the barrel, a filter located within the body of said
lining, and a launder arranged exteriorly of the barrel and
connected with said filter, substantially as described. (10.) A
filter of the class described, comprising a cylindrical rotatable
barrel provided with an acid-proof lining closely conforming
to the interior of the barrel and provided with a plurality of
circular series of perforations, pipes secured at the inner
ends to the lining about the circular series of perforations,
and a launder arranged on the exterior of the barrel and con-
nected to all of said pipes, for the purpose specified.
(Specification, 5s. 6d. ; drawings, 2s.)

No. 15871.—15th January, 1903.—Dr. HERMANN PASSOW,
of 33, Billhorner Röhrendamm, of Hamburg, Germany,
Manager. New and improved process for producing cement.

Claims.—(1.) Process of producing cement consisting in
mixing air-granulated slag of glassy structure or dried slag
sands, which in a ground state do not show any or only a

small rising in temperature when treated with carbonic acid,
with roasted water-granulated slags or with air-granulated
slags of pumiceous structure, which in a stream of carbonic
acid show a great rising in temperature, substantially as
described. (2.) The addition of a small quantity of a
normal Portland cement, or other materials containing
disposable lime, to the product of the process claimed
in claim 1, for the purpose of regulating the time of
setting or other qualities, substantially as described. (3.) A
modification of the process claimed in claim 1, characterized
thereby that to the slags not reacting with carbonic acid,
Portland cement, Roman cement, hydraulic lime, or other
substances containing disposable lime or forming such lime
are added instead of adding the slags reacting with carbonic
acid, substantially as described.
(Specification, 7s.)

No. 15873.—12th January, 1903.—EDWYN ALBERT HOL-
DEN, of Ashfield, Cumberland, New South Wales. An auto-
matic lubricator.

Claim.—For lubricating purposes, in combination, an
oil-cup, a contracted part or sump the bottom of which is
in the form of an inverted cone, a leak-hole at the apex of
the cone, a ball within the sump which shall overlie the
aperture of the leak when the apparatus is at rest, and a
hollow pillar extending upwards from the sump, such pillar
being provided with means whereby the oil may, by capillary
attraction, be conveyed from the oil-cup to the sump, as
specified.
(Specification, 2s. ; drawings, 1s.)

No. 15874.—14th January, 1903.—WILLIAM MCCALLUM,
of Kyeburn, Dredgeman, and EDWARD ROBERTS, of Dunedin,
Consulting Engineer, both of Otago, New Zealand. An
improved revolving screen.

Claims.—(1.) In revolving screens, the combination of the
usual circular ends, races, and gearing, with the screening
portion made and formed to an irregular cross-section for the
purpose of turning the material to be screened and within
the screen over and over to facilitate thorough screening, all
substantially as described and as explained, and as illus-
trated in the drawing. (2.) In revolving screens, in com-
bination, the usual races and gearing, with the whole body of
the screen made and formed to an irregular cross-section for
the purpose of turning the material to be screened and
within the screen over and over to facilitate thorough screen-
ing, all substantially as described and as explained, and as
illustrated in the drawing. (3.) In revolving screens, in
combination with the usual races and driving gearing, either
the screening portion or the whole body of the screen made
and formed to a polygonal form, substantially as and for the
purposes already set forth, and as illustrated in the drawing.
(Specification, 3s. ; drawings, 2s.)

No. 15877.—19th January, 1903.—JOHN WILSON TONG, of
New Plymouth, New Zealand, Builder. An improved
siphon.

Claims.—(1.) A siphon comprising a tube bent into U
shape, having one member of the U longer than the other, a
piston reciprocatable within the longer member, an air plug
or valve near the top of the apparatus and between the two
members, and a discharge tap or branch near the bottom of
the longer member, substantially as and for the purposes
specified. (2.) In a siphon for withdrawing liquids from a
containing-vessel, a piston reciprocatable within the longer
member of the siphon, an opening in the side of the piston
for the passage of liquid closable by a washer upon the
piston-rod, and a nut upon the end of the piston-rod adapted
to engage the underside of the piston when said rod is drawn
up. (3.) In apparatus for the purposes indicated and as
described, a reducing-socket upon the longer member of the
siphon, and a screw-cap for closing one end of the said re-
ducing-socket, substantially as and for the purposes specified.
(4.) In apparatus for the purposes indicated, the means de-
scribed for adjusting the depth of one member of a siphon
in the liquid upon which it is desired to operate, consisting
of a bridle surrounding the two members of the siphon, and
having a thumb-screw by means of which its position upon
the said members may be adjusted, substantially as and for
the purposes specified and illustrated.
(Specification, 3s. ; drawings, 1s.)

No. 15880.—15th January, 1903.—THOMAS HEWTON, of
Waianakarua, New Zealand, Mill-manager. Improved self-
tightening nut and washer.

Claims.—(1.) In bolts and nuts that are for use in places
where they are liable to be shaken loose, the combination of
a nut and washer formed to fit one another in the form of a