IMPROVEMENTS IN MAKING LITHOGRAPHIC STONES, BATHS, WASHING TUBS, SINKS AND OTHER ARTICLES OF PORTLAND CEMENT
Year: 1885

page_text: COMPLETE SPECIFICATION.
I, PETER WALKER, of 20, West Nicolson Street, Edinburgh, in the County of
Mid Lothian, North Britain, Plasterer and Cement Worker, do hereby declare the
nature of my Invention for IMPROVEMENTS IN MAKING LITHOGRAPHIC STONES,
BATHS, WASHING TUBS, SINKS AND OTHER ARTICLES OF PORTLAND CEMENT," and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, that is to say :-
My said Invention has for its object the making of lithographic stones, baths, .
washing tubs, sinks and other articles of Portland cement in a simple, economical
and expeditious manner. The cement being shaped into the desired form by
means of moulds having glass surfaces which render the surface of the moulded
articles very smooth and resembling a polished surface.
The mould which is used in making lithographic stones has for its bottom a
piece of polished plate glass of the size of which it is intended to make the stone.
The sides of the mould consist of pieces of wood or other material of a depth
corresponding to the intended thickness of the stone which is moulded with the
surface downwards, which is intended to be used for printing. The cement
employed is passed through a very fine sieve in order to separate objectionable
matters and is then made up into a plastic condition and filled into the mould. Or
the mould may be placed in water and the cement allowed to descend through the
water into the mould, this latter method preventing the possibility of "blown
holes" forming in the stone when hardened. When water is thus used it is
subsequently run off and the cement allowed to set after which the side pieces are
removed and the stone is left on the glass plate until sufficiently hardened.
In making baths, washing tubs, sinks and similar articles the sides of the mould
are formed by means of two frames of the desired shape open at top and bottom
one being placed inside the other, and the inside frame having fixed on its outer
surfaces pieces of plate glass. A piece of glass is also placed across the top of the
inner frame which piece of glass is shaped to form the bottom of the article which
is moulded upside down. The space between the glass surfaces on the inside frame
and the inside of the outer frame corresponds to the thickness of the article to be
moulded, and the cement is filled into this space at the top and the open surface
slecked over or smoothed level with the tops of the outer frame. After the cement
has sufficiently set the outer frame is removed to facilitate the hardening of the article.
Price di

page_text: Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is
1. Making lithographic stones, baths, washing tubs, sinks, and other articles
of Portland cement, by forming the same in moulds, having glass surfaces,
substantially as herein before described.
2. In the making of lithographic stones of Portland cement, the causing of the
cement in a finely sifted condition to sink through water in filling the mould
substantially as hereinbefore described.
EDMUND HUNT,
Applicant's Agent,
By Charles Aubrey Day.