IMPROVEMENTS IN THE PREPARATION AND LAYING DOWN OF BITUMINOUS ASPHALTE FOR PAVEMENT
Year: 1872

page_text: LETTERS PATENT to William Alexander Lyttle, of the Grove, Ham-
mersmith, in the County of Middlesex, Engineer, for the Invention
of "IMPROVEMENTS IN THE PREPARATION AND LAYING DOWN OF BITUMINOUS
ASPHALTE FOR PAVEMENT."
Scaled the 7th June 1872, and dated the 4th January 1872.
PROVISIONAL SPECIFICATION left by the said William Alexander
Lyttle at the Office of the Commissioners of Patents, with his
Petition, on the 4th January 1872.
I, WILLIAM ALEXANDER LYTTLE, of the Grove, Hammersmith, in
the County of Middlesex, Engineer, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE PREPARATION AND LAYING
DOWN OF BITUMINOUS ASPHALTE FOR PAVEMENT," to be as follows:-
I prepare an asphalte consisting of natural or artificial bitumen
mixed with any convenient earthy or silicious matter in a finely divided
state, or of natural asphalte, together in every case, with a non-drying

page_text: oil or fat, the object of such oil or fat being that the resulting asphalte
may thereby possess in some degree the character of shoemakers' wax,
and may so retain its elasticity and the tenacious adhesiveness with
which its particles when first prepared are held together. A good pre-
paration of this sort consists of about sixteen cwt. of finely powdered
chalk, three and three-quarter cwt. of pitch, natural or artificial, and
one-quarter cwt. of whale oil. A mixture of tallow and any non-drying
oil, such as a fish oil, or the hydrocarbon oil known as dead oil answers
well.
Fine sand or gritty matter or dry earth finely ground can be used
with or without the chalk, and the proportions of the pitch, fat, or oil
required will be found to vary according to the absorbent nature of the
earthy materials used. The bonding character of the pitch depends on
the degree of waxiness imparted by the oil or fat, and this must be
qualified as may be found best suited to each description of chalk, or
earth, or other mineral.
In order to prevent waste through destructive distillation of the pitch
and oil, or fat, I prefer to heat thoroughly the powdered chalk or earthy
matter before mixing it with the aforesaid bituminous wax, and for this
purpose I either spread the chalk or other powder upon a reverberatory
hearth, or cause it to pass slowly down a rotating cylinder, like those
used for sifting flour, whilst the hot gases from a furnace are made to
traverse this cylinder on their way to the chimney. The bituminous
wax and the hot chalk, earth, or sand are then mixed and thoroughly
blended together in a machine like that used in mixing brick materials,
or they may be ground together in a mortar mill, the mixing machine
or mill being kept hot. If the mixture should not appear of the proper
consistency, it can be qualified by an extra quantity of the deficient
ingredient.
In order to lay this asphalte, I either proceed in any of the well-
known modne MAN Mound in laxing natural
T
T

page_text: flame and hot gases from the furnace shall rush along the surface of the
concrete underneath the platform on their way to the chimney like the
flame in a reverberatory furnace. This will dry thoroughly and heat
the concrete, and whilst this is going on the platform can be employed
for the purpose of heating the aforesaid asphalte.
The platform may be made in moveable sections like the leaves of a
dinner table, so that when the concrete next to the furnace is dry one
or more sections of the platform may be taken up, transferred to the
chimney end, the chimney and furnace being advanced accordingly.
This asphalte can be heated in any other way now employed for such
purpose, but when heated on the aforesaid platform it should be supplied
broken as small as possible, and whilst heating it should be frequently
turned like malt on a kiln. This asphalte should be spread when hot,
and should be rolled or rammed level in a hot state.
5 SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said William Alexander Lyttle in the Great Scal
Patent Office on the 3rd July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALEXANDER LYTTLE, of the Grove, Hammersmith, in the County of
0 Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of January, in the year
of our Lord One thousand eight hundred and seventy-two, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,
5 give and grant unto me, the said William Alexander Lyttle, Her
special licence that I, the said William Alexander Lyttle, my exe-
cutors, administrators, and assigns, or such others as I, the said William
Alexander Lyttle, 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

page_text: 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 PREPARATION AND LAYING DOWN OF
BITUMINOUS ASPHALTE FOR PAVING," upon the condition (amongst others)
that I, the said William Alexander Lyttle, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office
within six calendar mouths next and immediately after the date of the
said Letters Patent.

page_text: the surface of the concrete to the chimney underneath the aforesaid
platform. The concrete would thus be superficially heated and dried,
and whilst this is going on, the upper surface of the platform can be
employed for the purpose of heating the asphalte prepared, as herein-
before described, or any other asphalte of a similar character.
This platform may be made in moveable sections something like the
leaves of a dinner table, so that when the concrete next to the furnace
is dry, one or more sections of the platform, with sides, may be taken
up and transferred to the chimney end, the chimney and furnace being
advanced accordingly. All the parts of this arrangement may, if desired,
be mounted upon castors or wheels, and the exclusion of the atmospheric
air from entrance underneath the platform may be effected by means of
ropes or sand bags laid in the same way as when such articles are
intended to prevent the passage of a draught of air under a closed door
or window.
This asphalte can be heated in any other way now employed for such
purpose, but when heated on the aforesaid platform it should be supplied
broken as small as possible, and whilst being heated it should be turned.
frequently like malt upon a kiln.
]
When this asphalte is made with a large proportion of wax or pitch 2
to the mineral powder, it may be laid in pasty state, but by increasing
the proportion of the mineral powder and thoroughly incorporating all
the ingredients in a hot state, a dry brown powder will be produced,
which can be rammed down or rolled in the same way as that adopted
in laying the asphalte designated "Val de Travers." The proportions 2
herein-before designated are intended to produce an asphalte of the
latter character.
Having now described the nature of my Invention, and some of the
best means known to me for carrying the same into effect, I wish it to
be understood that what I claim is,―
Firstly. The manufacture of asphalte, consisting of any finely divided
mineral powder incorporated in a hot state with wax, made as herein-
before described.
Secondly. Imparting a waxy character to natural asphalte by incor-
porating with it a non-drying fat or oil in a hot state.
3

page_text: Thirdly. Heating or drying the concrete foundation for this or any
other asphalte by converting it as described into the hearth of a portable
reverberatory furnace.
In witness whereof, I, the said William Alexander Lyttle, have
hereunto set my hand and scal, this Twenty-eighth day of June,
in the year of our Lord One thousand eight hundred and
seventy tin
In the presence of
HUNTLEY DAYER,
44, Mansion House Street,
Hammersmith, W.
W. A. LYTTLE. (L.S.)