IMPROVEMENTS IN THE CONSTRUCTION OF ROOFS OR COVERINGS OF BUILDINGS
Year: 1865

page_text: LETTERS PATENT to Felix Clovis Fourgeau, Builder, of 2, Rue Sainte
Appoline, Paris, (Empire of France,) for the Invention of "IMPROVEMENTS
IN THE CONSTRUCTION OF ROOFS OR COVERINGS OF BUILDINGS."
Sealed the 4th July 1865, and dated the 14th January 1865.
PROVISIONAL SPECIFICATION left by the said Felix Clovis Fourgeau at
the Office of the Commissioners of Patents, with his Petition, on the
14th January 1865.
I, FELIX CLOVIS FOURGEAU, Builder, of 2, Rue Sainte Appoline, Paris,
(Empire of France,) do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF ROOFS OR COVERINGS OF BUILDINGS,"
to be as follows :—
The main object of my Invention is to dispense with nails in the roofs or
coverings of buildings usually used for securing the slate or other material
thereto, and it consists in replacing the said nails by and in the employment
of, metal hooks or clasps for sustaining the said slates by holding them between
them and by fixing them to the frame, which may be of wood or metal, in
such manner that, no matter what power the wind may exert, the slates
cannot be raised or blown off the roofs of buildings, all as hereafter described.
The metal books or clasps are by preference made of metal wire bent in con-
trary directions at each end. At one end they may be pointed to facilitate

page_text: their insertion into the wood or metal; on the other end the hooks are
enlarged and carry the slate in the bent part, whereby contact of the slates
with one another is insured, permitting at the same time a free circulation of
air to preserve the slates and the frame, for the plan just described avoids all
infiltration of water.
The accompanying Drawings show the manner in which my Invention may
be carried into effect.
fis the hook or clasp secured at one end to a cross bar t, fixed as shown to
a rafter c; the other end of the hook or clasp carries a slate a. The hook or
clasp may be somewhat varied in shape to adapt it to the shape or size of the
slate employed and the construction of the framework. The different forms
of slates in use may be employed for the purposes of my Invention; however,
I prefer the lengthened octagon on account of its cheapness, of the facility
with which it is cut, and of its durability.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Felix Clovis Fourgean in the Great Seal Patent Office on
the 14th July 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FELIX
CLOVIS FOURGEAU, Builder, of 2, Rue Sainte Appoline, Paris, in the Empire
of France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of January, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Felix Clovis Fourgeau, Her special licence that I, the said Felix Clovis
Fourgeau, my executors, administrators, and assigns, or such others as I,
the said Felix Clovis Fourgeau, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF ROOFS OR COVERINGS OF BUILDINGS," upon
the condition (amongst others) that I, the said Felix Clovis Fourgeau, my
executors or administrators, by an instrument in writing under my, or their,
or one of their bands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to be

page_text: performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I; the said Felix Clovis Fourgeau, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
"The main object of my Invention is to dispense with nails in the roofs or
coverings of buildings usually used for securing the slate or other material
thereto, and it consists in replacing the said nails by and in the employment
of metal hooks or clasps for sustaining the said slates by holding them
between them, and by fixing them to the frame, which may be of wood or
metal, in such manner that no matter what power the wind may exert the
slates cannot be raised or blown off the roofs of buildings, all as hereafter
described.
The metal hooks or clasps are by preference made of metal wire bent in
contrary directions at each end; at one end they may be pointed to facilitate
their insertion into the wood or metal, on the other end the hooks are enlarged
and carry the slate in the bent parts, whereby contact of the slates with
one another is insured, permitting at the same time a free circulation of
air to preserve the slates and the frame, for the plan just described prevents all
infiltrations of water.
The accompanying Drawings show the manner in which my Invention may
be carried into effect. The hook or clasp may be somewhat varied in shape
to adapt it to the shape or size of the slate employed and the construction of
the framework. The different forms of slates in use may be employed for the
purposes of my Invention, but I prefer the lengthened octagon on account of
its cheapness, of the facility with which it is cut, and of its durability."
It is a well-known fact that slate resists for a very considerable length of
time the inclemencies of the seasons, therefore, the rapid deterioration of slate
roofing can only be attributed to the faulty method of construction generally
adopted. Slaters are unanimous in allowing that nails are insufficient for
preserving slates from the agitation of the wind, besides, the nails cause the
infiltrations of rain, which destroys at the same time the slate and the wood-
work, and necessitates difficult and costly reparations. These inconveniences
are in a great measure caused by the slight inclination often given to roofs at
the present day, and particularly by the false economy made in the nails, the
overlap of the slates and that of the scantling, and lastly by the mistaken use
of a part of the slate. Generally speaking the iron used for making the nails

page_text: is of inferior quality; the body of the nail wears tolerably well, but the head
is so thin that being bruised by driving it becomes more or less detached from
the body under the blows of the hammer without the workman being aware
of it, and rust promptly detaches this bead entirely. Endeavours have been
made to remedy this difficulty by using copper nails, but this metal, while
being very dear, is too easily adulterated to be relied upon. Besides, the
two-thirds of the slate which are overlapped insensibly absorb the damp, and
the slate gradually loses its consistence.
By the use of my improvements I do away with these inconveniences, no
longer employing the nails, but supplying their places with hooks made of
galvanised iron or copper, and as they are to be bent they can only be made
of iron of the best quality, much purer than that used for nail making; the
brass or copper hooks present the same guarantees.
This kind of slating may be fixed on wooden or iron framing as well as on
framings made of wood and iron together, and all kinds of slates may be used
whatever their forms and sizes.
The accompanying Drawings represent several examples of my improve-
ments. Fig. 1 and 2 show these improvements employed with slates of
different forms.
I have found that to obtain the best results it was suitable to form at each
side of the slates two small notches in which to place the hooks, so as not
to leave any space between the slates. Other notches proportioned to the
diameter of the hooks also exist in the ends of the slates in order to assure
the maintaining and fixing of the same, as represented in Figures 3, 4, 5,
and 6.
Figure 3 shows part of an ordinary slate roof fixed by hooks on wooden
battens, these battens may be broader than those generally used, or the space
existing between the battens may be filled by a light scantling, while leaving
an opening of two or three centimetres (an inch more or less) so as to facilitate
the free circulation of the air, as shown Fig. 3 and 4, A and B. The slates
placed at the edges are also held by hooks, but they are inclined towards the
gutters.
Figure 5 shows slates of an English form applied by means of hooks on a joist
work and lath framing of iron, the disposition is similar to the former one.
The upper angles C of this kind of slate are generally intended for the nails
so as to prevent the capillary infiltrations, but this mode of application has
but little strength, and its reparation is difficult, the hook on the contrary
holds the slate, particularly by the bottom, and, on account of this disposition
the part of the slate exposed to the air does not soften and never.rots, and the

page_text: hook pressing on the slate the latter cannot be agitated by the wind. The
leaden garnitures of the edges are made with a rib or shoulder projecting
above their surfaces, and are placed one in the other at each overlap; on
wooden lathwork they are fixed by nails placed at their upper ends on iron
batten work, they are fixed by hooks riveted to the ends of this batten work,
in all cases with an inclination or slope towards the gutter.
Fig. 7 shows a kind of pointed compass for tracing the divisions of the
battens and the overlap of the slates, seen Fig. 3 and 4, but for the slates
seen, Fig. 5 and 6, as they are longer they require compasses proportioned
to their dimensions, one for the battens and the other for the joints or
overlap. The distance between the battens depends upon the length of the
slates. The divisions of the battens should be made parallel to the gutter or
to the ridge of the roof. The last rows may be nearer to, but should
never be wider; they may even be closer at one end than at the other.
When the length of the part to be covered is unequal, false rows may also be
mado if necessary. The lines of the joints or ties should be made at right
angles with the battens.
Fig. 8 is a section size of execution of a slate fixed on a wooden frame-
work; the hook shown is not pointed at the outer extremity D, and by giving
it the bend shown at D' an empty space is left between the head of the hook
and the under side of the slate e, so that the slate F is isolated from the batten,
and thus the water which may enter the pores of the slate is allowed to run
off, and air is allowed to circulate in order to dry it, thus insuring great
durability without deterioration of the slate.
Fig. 9 is a section of a ridge on wooden framing, the rafters being joined as
usual, a wooden bracket is placed on the last two battens, fixed by stout nails
to the ends of the rafters; a band of zinc is placed at each side and held by the
last hooks; a cap or cover joint is placed and fixed by flat hooks on the
bracket.
Fig. 10 shows a section of a ridge mounted on iron framing, the ridge and
its purlins are of double T-iron, and the T-rafters are joined at the ridge by
a band of angle iron placed astride of the ridge at each side of the rafter at g.
The rafters may be joined by crossing the two blades of the rafters, held by a
bolt, or by riveting to the blade of one of the rafters a flat band of iron
forming a mortice, in which would be made to enter the blade of the other
rafter, also stopped by a bolt. This latter way of joining would have some
analogy with the mode used for wooden framing. On the purlin the rafter is
fixed by two bands of angle iron prepared beforehand and held on each side
of the rafter by two or more bolts, as seen at h, Fig. 10. If the two rafters

page_text: are joined the use of two bolts will be necessary. The T-rafter above-
mentioned has at its upper blades two slots, which allow of boring them when
fixed and in a cold state by choosing the thinnest places, and placing a bolt or
rivet so as to join the battens to the rafters. The skin i on the ridge, Fig. 10,
is made of sheet iron and descends on to the rafters, it is riveted or bolted to
the last or upper battens, after placing the slate a band of zinc is also applied
on each side and is fixed at its lower edge by the last hooks. A cylindrical
covering slid over the skin i from one end finishes and fixes the sheets of
zinc placed at the top. The joints of the skins should be opposite the rafters,
a mandrel formed of a lead pipe filled with plaster, and of the size of the
inside of the skin should be used for joining them and the zinc. Semi-
cylindrical hooks should be nailed in the joints and to the mandril, thus fixing
the covering, wooden mandrils may also be used. The same system is followed
for the corners or hips, except that the lead garniture which takes the place
of the ridge bands is bent under the slates at the bottom, and attached or
folded under the battens at the top. Any other form may be given to these
skins, or they may even be done away with by applying a simple band of
zinc or lead on the ridge, which should be fixed by the bent hooks, and on
the ribs or corners by hooks specially prepared for the purpose.
Fig. 11 is a section of the size of execution of an application of roofing on
iron framing. In some cases it is usual to imbed the slates in order to better
protect them against the action of the wind, but with my system this is not
necessary as the slates are perfectly well held. Should a hermetically closed
roof be required the slates could be fixed by applying a thin band of putty or
other substance under the part of the slate which is seen when in place.
Fig. 12 shows a pair of plyers intended for withdrawing the slates for
repairing. The projecting part of the hook is in the first place turned aside,
then, by raising the slate with the lower jaw of the plyers the slate is with-
drawn, and after replacing it by another the hook is bent back again. The
hooks à may be used for fixing any other matter capable of replacing the slate,
and they may be made of wire of an oval, square, or other section, but theso
forms offer less advantages than the ordinary round section.
Figures 13, 14, and 15 show my system applied to an iron framework in
Fig. 13, the batten k has ribs of unequal size, the larger blade is provided
with a slot in which enters the extremity of the hook, the batten is fixed to
the rafter by a holdfast i, Fig. 18s, which is riveted to the batten k. This
holdfast is united to the rafter m by a bolt, which also passes through a
thin part of said rafter in order to be able to bore the holes in a cold state,
and thus facilitate the mounting of the battens. The part of the holdfast

page_text: comprised between the rafter and th batten is pointed in order to facilitate
the placing of the hook, which would pass right or left of this piece were the
hook in this place.
Fig. 14 represents a two-armed iron batten o fixed to the rafter by a bolt
or rivet; this batten is like the rafter provided with a slot so as to pierce
these two pieces in a cold state; as each one is placed a wedge p is placed
between the two; it is seen in two projections, Fig. 14b.
Fig. 15 shows a disposition similar to the two preceding ones; here the
batten r is fixed on a V-shaped rafter which may be united to the purlin by a
piece of iron s, the ends of which after each passing through a hole made in
the bottom of the rafters are bent over on the ends of the purlin; however,
this iron s may be replaced by two holdfasts riveted or screwed. The
batten r is fixed to the rafters by two pins T, the ends of which are open and
bent down with the hammer after placing; generally the holes made in these
battens should be long in order to allow of the play required for the dilatation
and contraction of the iron; for the same reason a space must be kept
between the ends of the two battens, but if a hook falls on this joint, although
it is easy to deviate it by enlarging the hole or notch in the slate, it would be
preferable to cover the joint by a band of zinc or sheet iron counterbent
around the ends of these two battens.
Fig. 16 shows the rafter u made of T iron of a particular form; it may be
bored at the point u after placing, in order to fix the batten by two pins u¹
well driven and if necessary riveted; these two, pins u' may be replaced by
screws or small bolts.
(of the ordinary
Fig. 17 represents a rafter vand a batten x of iron
kind); these two are joined by a metal screw or by rivets. The joint of tho
battens is made by means of a sort of half round chamfered pin x, and the
ends of the battens are reserved (see Fig. 18). If the joint of two battens
happens to fall on a rafter the two ends a¹ may be crossed as seen Fig. 19.
The result of these improvements is a slate roof stronger and more lasting
than those of other systems, besides which my system considerably reduces the
expense of keeping in order and facilitates reparation, and even if necessary
allows of taking down the roof with but little expense, as all the slates may be
used again.
One of the distinctive features of this Invention is the iron or copper wire
book of remarkable simplicity and effect; this hook, the strength of which is
very superior to that of nails, fixes the slate by four different points, and offers
justly appreciated guarantees either on openwork battening or on lathwork
and scantling, which leave the under part of the slate exposed to the air, and

page_text: prevent its becoming impregnated with damp, which conditions are decidedly
advantageous for the preservation of the slate and woodwork, besides the hook
is fixed in the batten at about 15 millimetres (3 fifths of an inch) under the
upper end of the slate, and thus cannot communicate the damp nor attract
water as the nails sometimes do by the capillary action.
Lastly, the use of the hook allows of giving a long octagonal form to the
slate, which form gives great advantages to manufacturers, as it is well
known that right angles are difficult to cut and occasion much waste. Again,
this new form gives to the slate a much more uniform overlap and application,
giving more security against the collection and retention of damp. The hook
neither allows the use of too thin slates nor the diminution of the upper
overlap, and the battens cannot like the lath or scantling spring or shrink, and
thus deteriorate the roofing when finished.
Having thus described the nature of my said Invention, and the manner
in which the same is to be performed, I would have it understood that I claim
the exclusive property of the improvements introduced in the construction of
roofs of buildings as above described and represented in the accompanying
Drawings, that is to say, the use of the aforesaid hooks or clasps for the
purpose of fixing slates or other similar materials on the roofs of buildings,
and the peculiar mode of notching said slates, whereby they are held and fixed
when in place by four different points, thus allowing the use of long octagonal
shaped tiles or slates.
In witness whereof, I, the said Felix Clovis Fourgeau, have hereunto set
my hand and seal, this Fifth day of July, in the year of our Lord
One thousand eight hundred and sixty-five.