IMPROVE- MENTS IN MAKING ROADS AND WAYS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, MARCEL
JEAN MILON, of Rue Frouchet, in the City of Paris, in the Kingdom of
France, Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of the United Kingdom of Great Britain
and Ireland, bearing date at Westminster, the Eighth day of October, One
thousand eight hundred and forty-six, in the tenth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Marcel
Jean Milon, my exors, adiñors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said Marcel Jean Milon, my exors,
adñors, and assigns, or such others as I, the said Marcel Jean Milon, my
exors, adiñors, or assigns, should at any time agree with, and no others, from
time to time and at all times during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVE-
MENTS IN MAKING ROADS AND WAYS;" in which said Letters Patent is contained
a proviso, that I, the said Marcel Jean Milon, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited
Letters Patent, as in and by the same, reference being thereunto had, will
more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the said
Marcel Jean Milon, do hereby declare that the nature of my said Invention
and the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had
to the Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say:-
I will begin by stating that I have found that the carbonate of lime, which
has been always employed in the composition of the bitumenous mastic, which
is called "mastic factice," does not combine so well as could be desired with
mineral tar; and also that pure lime or hydraulic lime watered just enough
and no more than necessary to make it fall into impalpable powder, unites
perfectly well with bitumen, which, when in a state of fusion and very hot, is
rapidly absorbed by it. Coal tar, derived from the distillation from coal,, should
be separated from its volatile oil before it is employed in the composition
of bitumenous mastic; a degree of malleability may be given to it, which
preserves the low temperature, by means of vegetable fixed oils; it resembles
then the Bastennes tar, and can, if well prepared, have the same qualities.
First, I take it as it comes from the distillation of coal in the manufacturing
of gas, that is to say, in consistence, liquidity, viscosity, &c.; I put it in a
distilling apparatus with water, to extract from it its volatile principle, and
make it more dense. The volatile oil goes off with the steam, and both are
received in a condenser; I continue the distillation till the tar is deprived of
the pure volatile oil it contains in excess, and to give it the degree of ductility
which it should have in the bitumenous-mastic, I add to it from one to three
per cent of fixed oil, but particularly pyrogenous oil extracted from virgin
resin; the distillation is continued with a moderate fire until the tar attains
a consistence similar to that of Bastennes. When the tar is so prepared, I run
it off into a receiver or into barrels.
Of the Composition of the Mastic.-This mastic is composed of ordinary lime,
or hydraulic lime, or soft stone powder, with coal tar, prepared as I have
mentioned above; I put at different times into a copper placed on a fire
a proportion of seventy-five pounds of this tar, having its volatile oils removed
by distillation or otherwise, which must be melted with care; when it is liquid,
I add to it at different times, in order that the mixture may be well made with
the tar, one hundred pounds of ordinary lime, or hydraulic lime, slightly
damped with water to reduce it to a fine powder without depriving it of its
active property; I mix the whole carefully over, a moderate fire. When the
two substances are well mixed, the mastic is made, and I pour it into moulds

page_text: to form it into blocks, if not intended for immediate use. The proportions of
seventy-five pounds of tar with one hundred pounds of lime is not rigorously
fixed; it may be varied according to the quality of the lime, being made less
absorbent, and the degree of resistance which it is intended the mastic should
have, according to the temperature to which it is to be submitted. In order
to give my mastic the pliability and softness which it may preserve without
alteration, I add to it a proportion of pyrogenous oil or of prepared fixed oil.
Under certain circumstances and for special works, I substitute for lime,
powder made from stone of a calcareous nature, without any silica in it, the
powder being ground very fine; I warm it, in order that the tar may penetrate
it more easily, and mix more intimately with it; the proportion is the same as
that of lime, and I add to it either pyrogenous oil or coal tar in its viscous
state.
Of the Application.-The composition of my mastic, with which solid and
durable bitumenous coatings can be put on roads and ways, has a further
quality, which is a very important part of my Invention, and is one of its
advantages. It consists in the means of ascertaining with exactness the
quantum of resistance at different degrees of temperature.
Of the Manner of Operating.-If I employ mastic which has been already
manufactured, it ought to be put into the copper with a small quantity of tar
to help the melting of it. If it be made at the moment when it is required
for use, I mix together the materials, according to the proportions above men-
tioned. The mastic in the copper should be maintained at a degree of heat
of from 370 to 430 Fahrenheit. The mastic may in either case have almost
the same quantity of gravel added to it, namely, from 60 to 80 per cent. of its
weight. In order to ascertain the degree of consistence of the mastic before
it is employed, and when it is judged to be sufficiently hot, and after it has
been well stirred, the proof must be made as follows:-I take a small form or
mould made of a piece of thin iron, of which the sides are turned up at 0.47
of an inch on each side. This mould has a wooden handle (see Figure a).
Into this mould I put, with a wooden spatula, a small sample of the mastic
taken from the boiler. I flatten it by pressing it with the spatula to the level
of the edges of the mould, so as to make a small piece or sample of mastic
of 0.47 of an inch thick. I then fill a small pail, containing about two
gallons, with water at a temperature of 77 degrees Farenheit. The degree of
heat should be ascertained in every proof with a thermometer.
If the water
be too warm, cold water should be added to it; if the contrary be the case, the
temperature may easily be raised by plunging a hot iron into the water. The

page_text: sample of mastic should be plunged into the water, and moved about in it
quickly for two minutes exactly. It should then be taken out of the water
quickly, that the temperature may not change, and immediately after it should
be submitted to the proof following. This proof is made by means of an iron
stamp, having exactly the dimensions following:-The stamp (Figure 6) is a
quadrangular prism, of a pyramidal form, of which the height, 0.60 of an inch,
is equal to one of the sides of its base, also 0-60 of an inch. Two of these
stamps are placed opposite to each other on a small board, Figure c, of 23
inches in length, 1 inch thick, and 10 inches in width, to bring it on a level
with the sample of mastic, in order that the workman may stand firmly upon
it, and press equally with both feet. At the centre of the base of the stamp
there is a screw (Figure d), which serves to fix it on the board. Before the
stamp is used the corners should be slightly beaten in, and the point somewhat
blunted, in order that the impression may be at all times the same. The
sample of mastic should be put on a smooth horizontal plane of stone, or any
other hard body, and should be pressed. The point of one of the stamps.
.should then be placed on this sample, and that of the other on another sample,.
which has been already proved, and which is to be kept at a temperature of
25 degrees of heat by holding it in water heated to that temperature. A man
of the weight of about one hundred, and thirty-three or one hundred, and forty-
three pounds should-get- on the board, and press. the stamp on the sample,
moving backwards and forwards with a see-saw motion, that is to say, pressing.
alternately with his toes and heels for about ten seconds, which is the time
necessary for making the impression of the depth required in a square shape.
In default of a watch, the workman may count rapidly from one to forty, which
will serve to mark the seconds.. It is important that the workman should not
remain longer than ten seconds, because the impression being made in the pro-
portion of about 0.039 of an inch to a second, it is obvious that if he remain
even one or two seconds longer than necessary, the impression would be made
so much the wider, which would cause mistakes. This movement forces the
stamp into the mastic. When this proof is complete the stamp is shifted to
another part of the sample, when the same operation is
gone through, after
which the sample should be taken out as quickly as possible. The impressions
are then measured by a decimeter. If the impressions be equal, each of them,
for instance, 0.24 of an inch in diameter (which is the consistence of the
mastic of seyssel), the fire may be damped, or even extinguished; if, on the
contrary, the impressions should not be large enough, for example, only 0.21
of an inch, it would be necessary to put into the copper a small quantity of

page_text: pyrogenous oil in addition, until the impression required be obtained; and if
the impression should be too large, it would be necessary to increase the heat
so as to evaporate the bitumen, taking care to mix the mastic well. The oil
ought not to be put into the copper before the lime or powdered asphalt is
well incorporated with the tar. The whole should remain on the fire the
shortest time possible, that it may not thicken. The mastic is fit for use when
a white smoke issues from the copper.
When the mastic is of the consistence
required the fire should be extinguished, and the mastic immediately poured
out, for if kept beyond the time necessary an alteration may take place, the
composition may increase in density, and the mastic be too hard and unyielding
when laid on the road. When a good specimen has been obtained it should be
kept as a standard whereby to procure similar results under like circumstances.
If it be required to prepare the mastic for a road of which the bed is formed of
bitumen alone, the consistence of the mastic should be such as to take an
impression of 0.32 of an inch in diameter; but when it is to be used in the
formation of the paving blocks, of which mention will be made hereafter, the
consistence of the mastic ought to be of two kinds, namely, from 0.20 to 0:21
of an inch of the stamp for the bottom, and also for the sides, with the excep-
tion of 0.08 of an inch of the upper part of the sides, for which mastic of 0.47
of an inch of the stamp should be used, as that part will be on a level with the
upper part of the stones. I refer for the details on this subject to that part of
the description in which I speak of the stones cut in a regular form, and
which are called in Paris "paves smillés et repiqués." Instead of a man
being employed, scales may be used, made as shewn in Figure e. By this
means a given weight may be obtained to determine the depth and the
diameter of the impression, and thus a standard of weight and temperature
may be formed. It will be seen that for making the above proofs, water
at a temperature of 77 degrees, a weight of from 133 lbs. to 143 lbs.,
and a see-saw motion on the plank for 10 seconds, are necessary to force the
stamp into the mastic, to produce an impression sufficiently deep. All the
above directions should be strictly complied with to procure a good specimen
of the bitumenous mastic made after the above method, applicable to roads
and ways, observing that for a zone between 46 and 54 degrees of latitude, the
resistance of the mastic should be proved by its taking an impression of 0.32
of an inch. This will serve as a basis to determine the degree of resistance
for all the temperatures of the various climates, of the coldest as well as of the
hottest, to which the mastic may be exposed. This is the medium number of
a kind of scale of which the extreme points will be 5 and 95; but the tein-

page_text: perature between the 46th and 54th degrees of latitude is sometimes lower and
sometimes higher, but it is so only accidentally, and does not remain so long.
But it must be remembered that between these degrees there are various tem-
peratures; it will, however, always be easy to find the medium consistence
which must be adopted for each of them in giving greater resistance or more
softness to the mastic, in conformity with the degrees above mentioned, and I
will here observe that for roads and ways with bitumenous coatings under the
temperature of between 46 and 54 degrees of latitude, the consistence of 0.32
of an inch of the stamp is a very good one, for at 0.28 of an inch the mastic is
too firm, at 0.23 of an inch it is too hard, and at 0.26 of an inch it offers too
little resistance, thus, if the medium temperature of the place where the work
is to be carried on approach nearer to 5 degrees than to 95 degrees, it will
_ be necessary to make the mastic more malleable, capable of receiving an im-
pression of 0.32 of an inch; but if the medium temperature be of the opposite
degree, it will be necessary to give such firmness to the mastic that the
impression may be under 0.32 of an inch.
I will now describe a very important feature in my Invention, which is,
that all repairs of the bitumenous coatings of my roads can be made with
great facility, for example, it sometimes that in roads there are some slight
cavities, which necessarily must be filled up, so as to restore the level, this is
done by simply applying to the parts affected of the bitumenous coating, with
a hair brush, coal tar, oil of coal, or pyrogenous oil, as I have mentioned above,
and sprinkling them with pure lime powder, and afterwards with a small
quantity of sand, these substances unite, the whole is quickly consolidated, and
becomes firmly and fixedly incorporated with the original mass, thus the
bitumenous coating is made perfectly level and smooth, and by this means all
the cavities and irregularities on the surface of the road are made to disappear."
The thickness of the coating of bitumen is no hindrance to the repairs being
made; the ordinary method can be followed, namely, softening with hot
mastic the parts necessary to be surrounded to take up the required surface.
Foundation of the Road.-If the road upon which the bitumenous mastic is
to be laid be already constructed on the Macadam principle, it should be seen
that the existing surface is free from holes and ruts, that it is level and even;
if it be not in a good state it will be necessary to repair it and well ram it,
make solid and level the parts repaired, the dust should then be swept from
the surface as completely as possible, to facilitate the adhesion of the bitu-
menous substance to the stone, and to get rid of all the detritus, which would
be liable to swell from humidity or frost acting under the coating or bitumen..

page_text: But if an entirely new road is to be made, the first thing to be done is to
examine the ground and to ascertain the nature of the soil. The road is to be
constructed in the following manner :-The ground must be firmly compressed
by ramming it or by rolling it with a heavy roller, if practicable, then there should
be thrown upon it two layers of sand of two inches each, well beaten down
each time, which layers are to be watered, afterwards there should be placed
thereon a layer of small stones, of the size and shape of those used for Mac-
adamizing, and of the thickness of about six inches, taking care to put them
down on the surface without disturbing the sand; this layer of stones must
also be beaten down.. When this operation is finished a light layer of sand
should be put down to fill up the cavities, the road should be swept lightly to
remove the sand from the Macadam, the whole should then be watered to
make the sand go into the interstices, finally, a heavy roller should be passed
over the road, or it should be rammed down until the surface is quite even;
this should be done with great care. These layers of stony substances, if made
altogether of the thickness of ten inches, will be sufficiently solid; it is upon
these strata that the bitumenous coating is to be placed. I must here remark,
that I do not approve of the use of beton for foundations, it is expensive,
almost always useless, and frequently injurious to the composition laid on it.
Of the Bitumenous Coating.-I will commence by observing that for my
system to work well, it should be applied in summer, that is to say, from the
Fifteenth of April to the Fifteenth of September, and preferably at the com-
mencement of that period; the work which is executed during that season is
solid and durable, the temperature helping to consolidate the bitumen, for the
substance seems at such time to condense and to lose entirely the properties
which in the cold seasons tend to the formation of vesicles or cracks, which are
developped by traffick; the same effect may be produced by humidity in the
latter part of the year, or by the coldness of the soil in winter, which, in
lowering the temperature of the bitumen at the time of its being laid on,
renders it more unequal, and prevents its adhesion from being complete in all
its parts. This kind of road is not slippery when properly kept and watered,
but it has that defect when mud is left upon it, from the mud getting between
the horses' feet and the coating, a lateral inclination of 0.40 of an inch per yard
is sufficient for the drainage of the water that falls upon the road. For roads
which have a longitudinal inclination, the bitumenous mastic must not be em-
ployed alone, in such case stones cemented with it should be used. The mastic
to be used for this road ought to retain a certain softness, for which an im-
pression of 0.32 of an inch of the stamp will suffice, first, in order that the ruts

page_text: (which however are only apparent in very hot weather) may be effaced without
breaking up the mastic; secondly, that it may not be affected by any degree
of cold, and to enable it to yield with sufficient elasticity to the various weights
which may pass over it.
Application of my Mastic to Roads and Ways constructed with Hard Stone,
cut or uncut. Pavement made according to my system consists of hard stones
cut regularly, put into moulds, and cemented with my mastic, prepared at
different degrees of my stamp. The stones should be cut in that form which
is best adapted to the kind chosen for use, and which can be given to hard
stone. To render the solidity of this pavement complete, the following
methods should be scrupulously adhered to; first, the hardest stone proper for
paving should be chosen, it should be of an uniform quality, that its surface
may be worn equally, all soft stone should be rejected, such kind of stone
instance, as is used in Paris, which is brought from the valleys of L'Yvette, La
Marne, &c.; secondly, the stone must be cut into parallelopipeds, measuring
about six inches in width, five inches in height, and from eight inches to
twelve inches in length, Figure f; these dimensions I have found from
experience suitable, but other dimensions may be adopted, see Figure g. It is
adviseable that all the stones be cut regularly and with great care, that their
surfaces may be very even. When the stones necessary for making the
number of squares required for paving a given surface are prepared, the work
is performed in the following manner :-Of the form: the moulds into which I
put the stones, when cut, are composed of two large bands of wrought iron, as
in Figure J, placed opposite to each other, and of traverses, Figure K, put
between these two bands at regular distances; the opening of these traverses
is larger at the entrance than it is at the bottom, in order to permit of the
objects moulded passing out easily; the length of the iron band J is in proportion
to the number of blocks required to be moulded at one time. It is important
that the height of the moulds be exactly that of the stones, which should be all
of one uniform level, in order that the block may be equal every way, and so
as the under part of it may rest perfectly flat and even upon the bed of the
road, that the juxtaposition of the blocks may be perfect. The moulds must be
brought together by placing the iron bands and the traverses on long plates of
cast iron, put end to end, exactly horizontal, that the mould may be perfectly
regular; when the stones are to be put into the moulds, the traverses should
left for the reception of the
be placed at such a distance that the hollow part
stones may be wide enough for each division to contain nine stones of from
eight inches to ten inches long, disposed three in a row lengthwise, so as to

page_text: form a length of from twenty-four inches to thirty inches in three rows, placed
laterally with their points of junction opposed, these three rows being from
twelve inches to sixteen inches in width, Figure i. The stones must be placed
in the mould head downwards and flat on the plate of iron, but previously to
their being put in the interior of the mould should be washed with lime or
clay dissolved in water, to prevent the mastic sticking to it, Figure m. When
the mould is properly prepared, the stones should be taken out one by one and
placed in it, preserving between them a space of from 04 of an inch, to 0.5
of an inch wide, to allow the mastic to penetrate to the bottom of the inter-
stices, that the stones may be cemented together as firmly as possible, Figure n.
Great care should be taken that the stones be properly laid on the iron plate,
when they are placed it should be ascertained, by passing over them a very
exact line, whether they are even with the mould, if by chance some of them
should be found to jut out, they must be removed, cut to the required size, and
replaced. If the stones be warmed before they are put into the mould, it
would facilitate the adhesion of the mastic to them. When they are placed
in the position chosen, the mastic should be poured into the interstices,
of the consistence and in the manner about to be mentioned. I have
described, in my directions as to the application of my mastic for the
coating of roads, pages 6 and following, the method of proving the mastic, in
order to be sure of its degree of consistence, the same method should be
followed in applying the mastic to the cementing of hard stones, with this
exception, that in this latter case the mastic should be of two different degrees
of consistence. For this purpose the mastic should be put into the copper
pure, without any mixture of gravel in it; it should be prepared with great
care, and be very fine; its consistence should be ascertained by the method
above pointed out for testing the mastic employed in the coating of roads, as
the mastic is to be put between the paving stones, so as to fill completely all
the interstices of the blocks; it should be of the consistence of 0.5 of an
inch of the stamp. To pour in the mastic between the stones, a funnel with a
handle should be used, the mastic should be very liquid, that it may pass
easily through the neck of the funnel; the funnel should be put with care
between the stones, the mastic should be brought with a ladle and poured in
dexterously and lightly, in order that the man who holds the funnel may be
enabled to fill most completely all the interstices of the mould, and that
without spilling any on the ends of the stones; it must be poured in to an
uniform height of 0.8 of an inch, if by chance some of the mastic should fall
on the ends of the stones, it should be removed as quickly as possible,

page_text: with leaving any particle remaining, because this mastic being too soft,
it would prevent the other mastic from adhering to the stones.
I must
observe, that when the stones are put into the mould their ends are
reversed, that is to say, the stones are placed on their heads, but when the
operation is completed, and they are to be laid down, that which was the
under part will then be the upper part of the block. It remains now to
fill up the remaining parts of the interstices, in order that every hollow may
be effectually stopped; for this purpose, mastic, of the consistence of 0.24 of
an inch of the stamp should be employed, which mastic is consequently of
a greater consistence that that which was used for the former part of the
operation. This second application of mastic should be poured in without
the aid of the funnel, and should be poured in quickly, so as to prevent
the bitumen from cooling. The surface of the stones must be made quite
even, and small stones pressed as lightly and dexterously as possible into
the mastic which fills the interstices, care being taken that the paving stones
be not displaced, as the least disarrangement of them would be injurious. So
soon as the first layer is finished, I proceed with the others in like manner,
until the mould is filled up, after which I pass a very true level over the mould,
to level the mastic and make it quite even at the surface; this operation
finished, three-quarters of an hour should elapse before the mould is touched,
at the expiration of that time the iron bands may be taken out, but the
traverses should not be touched before the lapse of three hours, and when
they are taken out it must be done with care, so as to prevent the corners of
the stones from being broken. If it should be considered better that the
second batch of mastic should be poured into the interstices at twice, it may
be effected by dividing the height to be filled up into two parts, by this means
the formation of bubbles is avoided, and the perfect adhesion of the mastic to
the stones insured. Before the second layer of stones is placed in the mould, it
ought to be ascertained whether the first layer is as as complete in all respects
as is desired to be, and so on of all the rest; a level should then be passed
over, in the manner of a scraper, at right angles with the longitudinal iron
band, in order to make the surface quite even.
When the stones are thus
cemented, they may be removed in any convenient manner to a cool place,
take being taken that the shapes of them do not become injured.
The Manner of Laying Down the Blocks of Stones. Before the blocks are
laid down-there-ought-to be spread on the road between the levels, of 0.40 of
an inch thick, a layer of fine sand, well sifted from all grosser stony substances;
this layer should be even with the level, and should be spread with great care.

page_text: pave-
At one side of the road, at one of the ends thereof, a level of 0.40 of an inch
is to be placed transversely; opposite to this level there is to be placed another
level, of the like thickness, at the distance of 24 inches from the first level, by
which, consequently, an area of that width is marked off from the length of
the road; this space is to be filled with sand, which, by means also of a level,
is to be made even with the levels enclosing it; a space of the width of the
ment intended to be laid down is also to be measured off; .a cord is to be placed
upon the sand, and pressed upon it, in order to make a transverse impression
thereon; it is in this space that the blocks are to be laid down. Then a plank,
24 inches wide by 78 inches long, should be placed on the sand, which plank
is to be withdrawn from time to time as the work proceeds; it serves both to
press down the sand and for the workmen to stand on; to prevent their dis-
placing the sand a trestle should be put near to where the work is carrying
on; it ought to be 32 inches wide by 78 inches long. Upon this the blocks
intended for immediate use should be placed; two workmen should give their
special attention to this part of the work. A string should be passed under
and at each end of the blocks, in order that the workmen employed in laying
down the blocks may take them carefully and with facility to where they are
to be laid down, and without danger of any accident happening thereto.
These strings should not be withdrawn from the blocks until the whole width
of the road has been coated, to the end that if any of the blocks should happen
not to be properly placed the defect may be easily remedied. When it is ascer-
tained that the blocks are laid down as they ought to be, the strings may be
carefully withdrawn; half an hour after the laying down has been completed
the blocks should be lightly passed over with a wooden beater to efface the
marks left on the road by the strings. The stones should be brought upon
the road in the position in which they are intended to be laid down; the
blocks should have between them a space of from 0.4 of an inch to 0-6 of an
inch, to facilitate the introduction of the mastic between them; the interstices
must not be filled up before the expiration of five or six hours from the time
of the blocks being laid down; after which there should be poured into them,
at four different times, four separate layers of the mastic of which the blocks
are made; this is done to prevent any bulging in the blocks. The first batch
of mastic ought to be very fine and very liquid, of the consistence of 0.21 of
an inch to 0.24 of an inch of the stamp at the utmost, and poured into the
thickness or height of 0.40 of an inch, and should be poured in with a funnel,
so that the hollows between the stones may be filled up; the first and second
layers of mastic, of about 0-20 of an inch thick each for stones from 5 inches

page_text: to 6 inches high, should be also of the consistence of 0.21 of an inch to 0:24
of an inch of the stamp at the utmost at 25 degrees of heat. After the
second layer there should be left between the stones, where they are to be
joined, a hollow of 0.8 of an inch deep, to receive the third layer. Finally,
this hollow should be filled up with mastic of 0.5 of an inch of the stamp at
at the temperature of 25 degrees, as above mentioned. But now the work
ought to be proceeded with in a manner the very opposite to that which has
been followed in the making of the blocks, that is to say, in this stage of the
operation the blocks are to be placed with their tops or heads to the surface of
the road, whereas, when they were being made, their tops or heads were placed
flat down. This third layer of mastic is intended to remain at the point of
junction of the upper part of the pavement, and maintain its position by its
malleability in adjusting itself to the surface of the stones, and uniting with
the adjoining parts. There should not be any traffick on this road for four
hours at least after the execution of the works, that should any of the blocks
be imperfectly laid down they may have time to settle into their proper position.
This kind of road will stand any temperature, and bear almost any degree of
traffick upon it, without detriment to it either in sinking or otherwise. The
old hard material will serve to break up for further use. This method of con-
structing roads may also be successfully employed in the most abrupt ascents
without danger of the horses slipping, by making at certain distances grooves
across the road, which grooves would in fact be formed by the hollows, of 0.8 of
an inch where the blocks unite, as mentioned above, not being filled up with
mastic. When the blocks are brought together they resemble the Figure P.
Application of the Mastic to Roads and Ways made of Hard Stones of
Irregular Forms, or of Pebbles.-I prepare a mould made of iron bands, of
5 inches high and about 20 inches in diameter. I adopt the hexagonal or
quadrangular form with upright or curved sides, see Fig. O; this mould is
laid on a stone or cast-iron floor. As respects this matter I refer to what I
have said above. I put carefully in order the pebbles, which have been pre-
viously broken in two, for the purpose of giving to each part a flat surface; I
cut the stones as square as I can make them, in order to bring them as close
together as possible. To render the mass more solid, I lay the stones on the
flat part which is intended to form the surface of the road, keeping the other
end of the stones inwards; I then pour into the interstices, to the height of 0.8
of. an inch; mastic of 0.5 of an inch of the stamp, in the same manner as I
have before mentioned. When the stones are placed in the mould, it would
be as well, if convenient, to warm the mass, so as to take out all humidity

page_text: from them, and to render the mastic more adhesive. The round stones may
be easily broken in two with a paviour's hammer. I complete the filling up
of the moulds with small stones, placed in the best manner possible, so as to
avoid any hollow being left; for this purpose I employ mastic of 0.20 of an
inch of the stamp. The remainder of the operation is the same as that which
I have described above.
Recapitulation. My Invention consists in the discovery of new methods of
constructing roads and ways with a bitumenous mastic, prepared as I have
described, and made of different degrees of consistence, and in an entirely new
process of preparing the materials used in the formation of such roads and
ways, namely,
First, in the manner of manufacturing the bitumenous mastic with ordinary
lime or hydraulic lime, or soft stone, with prepared coal tar purified, and with
pyrogenous oil extracted from virgin resin, as above described. The discovery
of these combinations forms an essential part of my Invention, and I may justly
affirm that this composition has never been employed for the paving of roads
and ways.
Secondly, in the method of giving to the substance all the consistence re-
quired, and to determine positively its degree of malleability, aggregation, and
resistance on roads and ways, by means of a stamp and the impression made
therewith, which impression, increasing in size according to the degree of
pressure under circumstances which never vary, shews the degree of resistance
and density at a given temperature. I will remark, that the employment of
the stamp as a test is a very important feature in my Invention, for without this
controulling power great uncertainty would be experienced in the prosecution.
of the works, and that it appears to me the form given to this stamp is the
best that could be given to it for facilitating the operation, and is also the:
most convenient for measurements, as square impressions can be easily mea-
sured, but it may be of the conical or of any other form with equal effect, for it.
is the principle acted upon to produce the above results which I claim as my
Invention, independently of the method by which that principle is put into
execution.
Thirdly, in the manner of joining paving stones in blocks cemented with
mastic at different degrees of consistence.
Fourthly, in the method of repairing the bitumenous coating of roads and
ways, in order to remove all inequalities. and fissures therein by passing over
them, as I have before observed, with a brush, coal tar produced from the dis-
tillation of gas or other oils, before mentioned, sprinkling it with lime, and

page_text: throwing sand upon it. This method is altogether new; it is efficacious, and
allows of the repairs being made expeditiously and at a small expence.
In conclusion, I further remark, that each of the processes above described
is in itself a new process, and that all such processes combined form likewise a
process which is entirely new as applied in the manner above stated; it is,
therefore, which I claim as exclusively of my Invention.
In witness whereof, I, the said Marcel Jean Milon, have hereunto set
my hand and seal, this First day of April, in the year of our Lord
One thousand eight hundred and forty-seven.
MARCEL JEAN (L.s.) MILON.
Taken and acknowledged by Marcel Jean Milon,
_ (party hereto,) at Paris, in the Kingdom of
France, this First day of April 1847, before me,
THOMAS PICKFORD.

page_text: AND BE IT REMEMBERED, that on the oath of William Henry
Ritchie the Specification aforesaid was enrolled word for word as above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Eighth day of April, in the year of our Lord One thousand
eight hundred and forty-seven.