Year: 1887

page_text: Date of Application, 18th May, 1887
Complete Left, 14th Feb., 1888
Complete Accepted, 23rd Mar., 1888
I, LEWIS GODFREY KNEMEYER of 49 Bedford Street, Strand W.C. and 2 Wellesley
Villas, Westbourne Road, Forest Hill (Kent) Manufacturers Agent do hereby declare
the nature of the said invention to be as follows:-
The Cement is a mixture of about 2 parts ground Tophus (Tufa), 1 part Lime and 1 part
Portland Cement. Its value consists in the fact, that it is not subject to efflorescence
or air cracks like other cements, but can be painted on without risk as soon as the
material is dry.
The invention is specially intended
1) for moulding artificial Stone work and ornamental features (such as columns,
cornices, friezes, pilasters, vases, slabs etc.) The natural colour is an oven light
grey, which is unchanged by time and exposure, and is in itself an admirable
finish.
2) for coating walls etc., either inside or outside of buildings, with a suitable
surface for the reception of weatherproof artistic painting in oil, watercolours, alfresco
or other decorative work.
3) for mixing hydraulic Mortar or Concrete by a proportionate admixture of Sand
or Gravel.
For coating walls etc. this Cement is to be mixed with water only, kneaded and
battered until it forms a plastic mass, wherewith the rough brick or stone-wall is to be
rendered and floated. This Cement does not harden and dry so quickly as other
cements, according to circumstances its hardening process will require from 3 to 6 weeks,
when it will get as hard as any stone. During the first week the surface should be
frequently besprinkled with water. When the material is perfectly dry, the surface is
to be cleansed and washed with a mixture of 1 part Muriatic Acid and 3 parts
water.

page_text: The next day the ground is ready for painting, but before commencing it the
ground is to be brushed over with a mixture of 1 part Waterglass and 3 parts
Water.
For painting on this Cement many mineral (earth) colours can be employed, and by
its use great difficulties hitherto obstructing the art of alfresco painting are removed.
Experiments can be made whilst the design is in progress, mistakes and failures can
easily be removed and painted anew.
When dry, the colours are to be fixed with a mixture of 1 part Fixativo
(consisting of 9 parts Waterglass and 1 part Sal-Ammoniac NH.) and 4 parts hot, not
boiling, water, which is to be brushed over with a soft brush 3 or 4 times in
intervals.

page_text: COMPLETE SPECIFICATION.
Cement Adapted for Artificial Stone-work and for Coating Walls
with a Suitable Surface for the Reception of Weatherproof
Painting.
I, LEWIS GODFREY KNEMEYER, Cement-Maker, of No. 2 Wellesley Villas,
Westbourne Road, Forest Hill (Kent) 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 :-
The Cement is a mixture of about 4 parts fine ground Tufa-stone, a natural volcanic
product, which, on account of its porousness, is especially adapted for the reception
and absorption of colours without spoiling their effect.
2 parts Portland-Cement, natural or artificial.
1 to 2 parts ground Lime, such as Dorking greystone, blue Lias and similar
sorts.
The admixture of Lime is to be in accordance with the proportion of Lime contained
in the Portland-Cement; should this contain 60% Lime or more, the quantity of
Lime for admixture can be reduced to 1 part or even less.
The parts are to be taken by measure, and the three materials well mixed, dry, in a
trough, drum or other apparatus.
The following directions for use should be observed:
For wall coating and decorative painting the Cement is to be mixed with water
only, well stirred and battered until it forms a plastic, not crumbling mass, like
glaziers putty. Before rendering the rough wall is to be watered, and, in order to
get a fine granular surface, the floating should be done with a wooden or felt
float.
To prevent air-cracks, the surface should be sprinkled frequently with water during
the first week and also be protected against sun and frost. As soon as the material is
dry the surface is to be washed with a solution of 1 part Muriatic Acid and 3 parts
water; the following day it can be painted on. Before commencing this work, the
painting-ground is to be washed with a solution of 1 part Fixative (a mixture of
9 parts Silicate of Soda and 1 part Ammonia NH,) and 4 parts water.
For painting on it none but the finest ground, pure earth or mineral colours should
be employed, with plenty of water and soft brushes in order to prevent the
formation of crusts on the painting-ground. The colours dry quickly and when the
work is finished, it is to be brushed over, slightly, with a soft flat brush, in intervals
two or three times, with 1. part, Fixative (described before) and 4 parts water mixed
together.
For moulded work, the mould is first to be coated carefully with the Cement in a
plastic state, and afterwards filled up with mortar or concrete. The block should be
kept in the mould for a few days; when dry and hardened the features can be treated
and painted in the same manner as a plain surface.

page_text: The Cement can also be coloured throughout in various tints by adding about
5% pure earth or mineral colour, dissolved in water and mixed with the Cement
until it forms a plastic mass; 1 part coloured water being required for 2 parts
Cement.
For general building purposes and for hydraulic works this Cement is to be treated
like Portland-Cement.
Having now particularly described and ascertained the nature of my said Inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1) The manufacture of a Cement, suitable for the above mentioned purposes and
consisting of ground Tufa-stone, Portland-or other Cement containing similar
ingredients, and Lime.
2) In combination with this Cement, the manner of painting on it in watercolours
as described.
3) In combination with this Cement, the manner of colouring it throughout as
described.
1
1000
LEWIS GODFREY KNEMEYER.