Year: 1887

page_text: Date of Application, 18th July, 1887
Complete Left, 29th Mar., 1888
Complete Accepted, 25th May, 1888
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E. do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in roofs, principally flat roofs and roofing
material which because of its quality and construction as well as the mode of
applying it forms a very solid roof and prevents any danger of leaking or expansion
of the material employed.
The squares or flags composing the paving of the roof consist of a mixture of
hydraulic or Portland cement and sand covered on the outside with a mixture
of hydraulic lime or a special cement and any suitable mineral coloring material.
The whole is slightly damped and submitted to hydraulic pressure in special moulds.
Some three days after the moulding the squares are immersed in water for a few
hours for the perfect union of its component parts.
The squares or flags thus obtained are of great resistance and strength.
The squares are of such construction that they form a butt joint on one side and
a lap joint on the other. The frame of the roof consists entirely of double channel
or H section irons on which are placed angle irons with the angle downwards
resting in suitable chairs. The squares or flags are placed on these angle irons
which are laid down at such distances that the butt joints of the squares are
immediately above them; they thus form gutters for any water which might filter
through the joints.
T
1011
Tl 1007
2

page_text: I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E. 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 :-
This invention relates to improvements in roofs, principally flat roofs, and roofing 5
material which because of its quality and construction as well as the mode of
applying it forms a very solid roof and prevents danger of leaking from the expansion
or contraction of the material employed.
"
In the accompanying drawings.
Fig. 1 represents a plan view of the top of a portion of a roof constructed according 1
to this system.
Fig. 2 is a plan view of the bottom of the same.
Fig. 3 is a section on line X Y of figure 1.
Fig. 4 is a section on line X' Y' of figure 2.
The squares or flag C composing the paving of the roof consist of a mixture of 1
hydraulic or Portland cement and sand covered on the outside with a mixture of
hydraulic lime or a special cement and any suitable mineral coloring material. The
whole is slightly damped and submitted to hydraulic pressure in special moulds.
Some three days after the moulding the squares are immersed in water for a few
hours for the perfect union of their component parts.
2
The squares or flags thus obtained are of great resistance and strength.
The squares are of such construction see figures 3 and 4 that they form a butt
joint on one side and a lap joint on the other. The frame of the roof consists
entirely of double channel or H section_irons A B placed at right angles to each
other, on which are placed angle irons E with the angle downwards and resting in 2
suitable chairs D.
The squares or flags C are placed on these angle irons which are laid down at such
distances that the butt joints of the squares are immediately above them; they thus
form gutters for any water which may filter through the joints.
Having now particularly described and ascertained the nature of the said invention, a
as communicated to me by my. foreign correspondents, and in what manner the
same is to be performed, I declare that what I claim is :-
The system of constructing flat or other roofs characterized essentially by:
1. The employment of squares or flags such as C forming the paving and produced

page_text: by moulding under strong pressure a mixture of Portland or hydraulic cement and
sand and covering this with a composition of hydraulic lime or special cement and
mineral color, the whole being slightly moistened after the moulding for the union
of the component parts.
2. The arrangement of the squares or flags C on the iron frame of the roof con-
sisting of the angle irons E resting in suitable chairs D on the double channel irons A
the said angle irons E supporting the squares C and forming gutters for the removal
of any water which might filter through the joints between the squares C.
The whole substantially as described and illustrated in the accompanying drawings.
Dated this 29th day of March 1888.