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being also killed。〃*＇2＇ The remaining part of the bridge continued
for some time unrepaired； just space enough being left for a single
carriage to pass。 The road trustees seemed to be helpless； and did
nothing； a local subscription was tried and failed； the district
passed through being very poor； but as the road was absolutely
required for more than merely local purposes； it was eventually
determined to undertake its reconstruction as a work of national
importance； and 50；000L。 was granted by Parliament with this
object； under the provisions of the Act passed in 1816。 The works
were placed under Mr。 Telford's charge； and an admirable road was
very shortly under construction between Carlisle and Glasgow。
That part of it between Hamilton and Glasgow； eleven miles in length；
was however left in the hands of local trustees； as was the
diversion of thirteen miles at the boundary of the counties of
Lanark and Dumfries； for which a previous Act had been obtained。
The length of new line constructed by Mr。 Telford was sixty…nine
miles； and it was probably the finest piece of road which up to
that time had been made。
His ordinary method of road…making in the Highlands was； first to
level and drain； then； like the Romans； to lay a solid pavement of
large stones； the round or broad end downwards； as close as they
could be set。 The points of the latter were then broken off； and a
layer of stones broken to about the size of walnuts； was laid upon
them； and over all a little gravel if at hand。 A road thus formed
soon became bound together； and for ordinary purposes was very
durable。
But where the traffic； as in the case of the Carlisle and Glasgow
road； was expected to be very heavy； Telford took much greater
pains。 Here he paid especial attention to two points： first； to lay
it out as nearly as possible upon a level； so as to reduce the
draught to horses dragging heavy vehicles；one in thirty being
about the severest gradient at any part of the road。 The next point
was to make the working； or middle portion of the road； as firm and
substantial as possible； so as to bear； without shrinking； the
heaviest weight likely to be brought over it。 With this object he
specified that the metal bed was to be formed in two layers； rising
about four inches towards the centre the bottom course being of
stones （whinstone； limestone； or hard freestone）； seven inches in
depth。 These were to be carefully set by hand； with the broadest
ends downwards； all crossbonded or jointed； no stone being more
than three inches wide on the top。 The spaces between them were
then to be filled up with smaller stones； packed by hand； so as to
bring the whole to an even and firm surface。 Over this a top course
was to be laid； seven inches in depth； consisting of properly
broken hard whinstones； none exceeding six ounces in weight； and
each to be able to pass through a circular ring； two inches and a
half in diameter； a binding of gravel； about an inch in thickness；
being placed over all。 A drain crossed under the bed of the bottom
layer to the outside ditch in every hundred yards。 The result was
an admirably easy； firm； and dry road； capable of being travelled
upon in all weathers； and standing in comparatively small need of
repairs。
A similar practice was introduced in England about the same time by
Mr。 Macadam； and； though his method was not so thorough as that of
Telford； it was usefully employed on most of the high roads
throughout the kingdom。 Mr。 Macadam's notice was first called to
the subject while acting as one of the trustees of a road in
Ayrshire。 Afterwards； while employed as Government agent for
victualling the navy in the western parts of England； he continued
the study of road…making； keeping in view the essential conditions
of a compact and durable substance and a smooth surface。 At that
time the attention of the Legislature was not so much directed to
the proper making and mending of the roads； as to suiting the
vehicles to them such as they were； and they legislated backwards
and forwards for nearly half a century as to the breadth of wheels。
Macadam was； on the other hand； of opinion that the main point was
to attend to the nature of the roads on which the vehicles were to
travel。 Most roads were then made with gravel； or flints tumbled
upon them in their natural state； and so rounded that they had no
points of contact； and rarely became consolidated。 When a heavy
vehicle of any sort passed over them； their loose structure
presented no resistance； the material was thus completely
disturbed； and they often became almost impassable。 Macadam's
practice was this： to break the stones into angular fragments； so
that a bed several inches in depth should be formed； the material
best adapted for the purpose being fragments of granite；
greenstone； or basalt； to watch the repairs of the road carefully
during the process of consolidation； filling up the inequalities
caused by the traffic passing over it； until a hard and level
surface had been obtained。 Thus made； the road would last for
years without further attention。 in 1815 Mr。 Macadam devoted
himself with great enthusiasm to road…making as a profession； and
being appointed surveyor…general of the Bristol roads； he had full
opportunities of exemplifying his system。 It proved so successful
that the example set by him was quickly followed over the entire
kingdom。 Even the streets of many large towns were Macadamised。
In carrying out his improvements； however； Mr。 Macadam spent several
thousand pounds of his own money； and in 1825； having proved this
expenditure before a Committee of the House of Commons； the amount
was reimbursed to him； together with an honorary tribute of two
thousand pounds。 Mr。 Macadam died poor； but； as he himself said；
〃a least an honest man。〃 By his indefatigable exertions and his
success as a road…maker； by greatly saving animal labour；
facilitating commercial intercourse； and rendering travelling easy
and expeditious； he entitled himself to the reputation of a public
benefactor。
＇Image＇ J。 L。 Macadam。
Owing to the mountainous nature of the country through which
Telford's Carlisle and Glasgow road passes； the bridges are
unusually numerous and of large dimensions。 Thus； the Fiddler's
Burn Bridge is of three arches； one of 150 and two of 105 feet span
each。 There are fourteen other bridges； presenting from one to
three arches； of from 20 to 90 feet span。 But the most picturesque
and remarkable bridge constructed by Telford in that district was
upon another line of road subsequently carried out by him； in the
upper part of the county of Lanark； and crossing the main line of
the Carlisle and Glasgow road almost at right angles。 Its northern
and eastern part formed a direct line of communication between the
great cattle markets of Falkirk； Crief； and Doune； and Carlisle and
the West of England。 It was carried over deep ravines by several
lofty bridges； the most formidable of which was that across the
Mouse Water at Cartland Crags； about a mile to the west of Lanark。
The stream here flows through a deep rocky chasm； the sides of
which are in some places about four hundred feet high。 At a point
where the height of the rocks is considerably less； but still most
formidable； Telford spanned the ravine with the beautiful bridge
represented in the engraving facing this page； its parapet being
129 feet above the surface of the water beneath。
＇Image＇ Cartland Crags Bridge。
The reconstruction of the western road from Carlisle to Glasgow；
which Telford had thus satisfactorily carried out； shortly led to
similar demands from the population on the eastern side of the
kingdom。 The spirit of road reform was now fairly on foot。
Fast coaches and wheel…carriages of all kinds had become greatly
improved； so that the usual rate of travelling had advanced from
five or six to nine or ten miles an hour。 The desire for the rapid
communication of political and commercial intelligence was found to
increase with the facilities for supplying it； and； urged by the
public wants； the Post…Office authorities were stimulated to
unusual efforts in this direction。 Numerous surveys were made and
roads laid out； so as to improve the main line of communication
between London and Edinburgh and the intermediate towns。 The first
part of this road taken in hand was the worstthat lying to the
north of Catterick Bridge； in Yorkshire。 A new line was surveyed by
West Auckland to Hexham； passing over Garter Fell to Jedburgh； and
thence to Edinburgh； but was rejected as too crooked and uneven。
Another was tried by Aldstone Moor and Bewcastle； and rejected for
the same reason。 The third line proposed was eventually adopted as
the best； passing from Morpeth； by Wooler and Coldstream；
to Edinburgh； saving rather more than fourteen miles between the
two points； and securing a line o