Improvements in the Manufacture of Spiral Tubes, Rods, Pedestals, Chimney Pots, Architectural Mouldings, and such like Articles of Terra Cotta or other Earthenware, and in Apparatus to be Used for this Purpose.
Year: 1887

page_text: Date of Application, 19th July, 1887
Complete Left, 19th Apr., 1888
Complete Accepted, 25th May, 1888
Improvements in the Manufacture of Spiral Tubes, Rods, Pedestals,
Chimney Pots, Architectural Mouldings, and such like Articles
of Terra Cotta or other Earthenware, and in Apparatus to be
Used for this Purpose.
We, HENRY LEWIS DOULTON of Lambeth Pottery, London, S.E., Potter, and
MARK MARSHALL of 31 Aytoun Road, Stockwell, Designer, do hereby declare the
nature of this invention to be as follows:-
We manufacture tubes or rods of any desired cross section and in a spiral form by
expressing plastic clay earth through a spirally formed die of the cross section and
pitch required.
The stream of clay we cause to issue downwards from the die so that it may turn
freely and in cases where a certain amount of support has to be given to the stream
to prevent it from breaking we support it upon a surface which not only can descend
with the stream of clay but can also readily revolve with it.
Chimney tops, umbrella stands, pedestals and such like may be made with their
central portion only of the spiral form and with a head and foot separately moulded
and made to adhere to them before burning.
Moulded figures or ornaments in plastic clay can also be applied to the side sin the
spiral grooves and made to adhere before burning the grooves giving great facility for
fixing them in place.
By applying figures or ornaments in this way undercut work can readily be
produced which otherwise could only be obtained at considerable expense.
In architectural work spiral mountings can also be produced in the same way and
applied in any desired position upon the clay block before firing or while in the
soft state.
For chemical manufactures in processes of evaporation or condensation tubes or
rods of pottery ware may be made by the above nained method thereby obtaining
increased condensing area in the same cubic space.
CARPMAEL & Co.,
Agents for the Applicants.

page_text: Improvements in the Manufacture of Spiral Tubes, Rods, Pedestals,
Chimney-pots, Architectural Mouldings, and such like Articles
of Terra Cotta or other Earthenware, and in Apparatus to be
Used for this Purpose.
We, HENRY LEWIS DOULTON of Lambeth Pottery, London, S.E., Potter, and
MARK MARSHALL of 31 Aytoun Road, Stockwell, Designer, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
We manufacture tubes or rods of any desired cross section and in a spiral form by
expressing plastic clay earth through a spirally formed die of the cross section and
pitch required.
The spiral passage through the die we make of the same size and section for a short
distance which will vary say from a quarter of an inch to an inch in length according to
the form of the die and the nature of the clay. As the clay is being expressed it
travels through the die in the direction of the spiral and so acquires a revolving motion
and continues to rotate after leaving the die.
The stream of clay we cause to issue downwards so that it may turn freely and it
may either be allowed free play or in cases where a certain amount of support has to
be given to the stream to prevent it from breaking we support it upon a surface
which not only can descend with the stream of clay but can also readily revolve
with it.
The drawing annexed shews an elevation partly in section of an apparatus formed
in this way.
A is a piston which can be forced downwards into a cylinder B filled with clay.
C is the die with spiral passage through it. D the issuing stream of clay. E is a
revolving table by which the lower end of the stream of clay is supported. The pivot
of this table turns in a bearing in a frame F which can rise or fall in guides in the
vertical standards of the frame.
The frame is counterbalanced by weights G as shewn.
Chimney tops, umbrella stands, pedestals and such like may be made with their
central portion only of the spiral form and with a head and foot separately moulded
and made to adhere to them before burning.
Moulded figures or ornaments in plastic clay can also be applied to the sides in the
spiral grooves and made to adhere before burning the grooves giving great facility for a
fixing them in place.
By applying figures or ornaments in this way undercut work can readily be
produced which otherwise could only be obtained at considerable expense.
In architectural work spiral mountings can also be produced in the same way and
applied in any desired position upon the clay block before firing or while in the soft a
state.

page_text: For chemical manufactures in processes of evaporation or condensation tubes or
rods of pottery ware may be made by the above named method thereby obtaining
increased condensing area the same cubic space.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what
we claim is :-
1. The manufacture of spiral tubes rods pedestals, chimney pots, architectural
mouldings and such like articles of terra cotta or other earthenware by expressing
plastic clay through a spirally formed die.
2. The manufacture of spiral tubes rods pedestals chimney pots, architectural
mouldings and such like by expressing plastic clay downwards through a spirally
formed die and supporting the stream of clay as it issues from the die upon a counter-
balanced revolving table which can descend with it.
3. The combination of clay-expressing apparatus spiral die and counterbalanced
revolving table for supporting the stream of clay which issues from the die
substantially as described.
H. L. DOULTON.
M. MARSHALL.