In Australia there appears to be a continuum between a variety of scientific
roadmaking systems, commencing in the 1830s and 40s and leading to
standardised construction methods under the various colonial road and
transport departments by the late nineteenth century. The following is a
brief summary. I would be interested to see how this compares to American
practice.

ROADS IN AUSTRALIA
Knowledge of road engineering came to Australia from Great Britain, and in
particular through the British Parliamentary Select Committees of the early
1800s whose witnesses included Thomas Telford and John Loudon MacAdam.
Both men devised schemes for road construction that put emphasis on good
drainage, the creation of a hard durable pavement surface and the
minimisation of convexity. MacAdam favoured raising the roadway above the
ground and building up layers of broken stone no less than 2 inches in
diameter over a curved base. Telford's designs involved excavating
foundations below the surface, and laying large tightly packed stones over a
flat base with larger stones to the centre to provide curvature. A six inch
surface of small broken stone or clean gravel was placed over the large
stones. Binding such as clay was used to seal the surface to prevent water
seeping down to the foundations.

New South Wales Engineer Soldiers from the Royal Engineers took over road
construction in 1820. The first civil road authority was the Roads and
Bridges Department formed in Tasmania in 1827 and the first district Roads
Trusts or Boards were set up in 1840 in Tasmania, NSW and Victoria. The
source of their scientific engineering when it did come, was the Treatise on
Telford's Road-making methods produced by Sir Henry Parnell in 1833, and
picked up by Lord Elgin, Secretary of State for the Colonies who considered
it essential for his colonial officers to be informed of the Telford
methods.

ROADS IN VICTORIA
Hoddle's Melbourne Town Plan set the precedent for wide streets and roads
(supposedly to allow bullock teams to turn around).
Convict labour was used for some road making in 1837 in Melbourne. NSW
Government was responsible for roads in the Port Phillip district from 1836
to 1851 (separation and creation of the Colony of Victoria) but its Public
Roads Act of 1833 was not applied in Victoria and little planning or
construction was undertaken, or road finance provided. Some land was
surveyed without provision for road reserves, and what roads existed were
impassable in wet weather.
The first macadamised road (constructed on a formed and drained crushed
stone base) was part of  a 13 km section of the Great Heidelberg Road built
between 1842 and 1848 by a private trust and financed by a toll gate in
1847. In 1848 it was described as "the only made road in the colony ... hear
and there as we went along there were neatly piled heaps of broken stone,
just as you see in England..." (Kenyon 1934, MG Lay 1984).
David Lennox came to Melbourne as superintendent of Bridges.

In 1851 when Victoria became a separate colony, there were still no surfaced
roads outside Melbourne and Geelong and roads became the chief item of the
new Government's expenditure. In November 1851 a committee to inquire into
the deplorable condition and alignment of the roads was established which
drew heavily on the work of Hoddle and Lennox.

The Central Roads Board was created in 1853 with powers over the main roads
and District Roads Boards for minor roads. Expenditure increased tenfold
with the windfall of taxes from the gold rushes and massive immigration so
that by 1855 some 300 km of road had been surfaced. By 1860 some 800 km of
passable roads were in existence. The Central Roads Board was disbanded in
1863 and its functions gradually transferred first to the District Roads
Boards and eventually the shires. While there were 125 tollgates in Victoria
in 1870, tolls were abolished by an Act of Parliament in 1877.

The District Roads Boards were abolished in 1869 and the rate of road
construction rapidly declined in the face of competition with railways.
The adoption of the motor car in the early twentieth century put pressure on
a road system built for horse and cart so that in 1913 the Country Roads
Board was formed.
· A general road plan
· Macadamised roads
· A Central Roads Board

TELFORD SYSTEM
Thomas Telford was one of the greatest engineers of the nineteenth century.
He applied scientific methods and an understanding of the properties of
earth and stone to road building. He devised a number of construction
techniques for road construction, one of which has been synonymous with his
name. The Telford System involves the following stages:
· Excavating the road base to provide a level bed below the soil surface and
on a regular gradient less than 1 in 24.
· Laying large stones along the sides of the road to form a firm shoulder to
contain the base of the road. Sometimes an additional line is laid down the
centre to form the apex of the road.
· Filling in between the shoulders with base stones measuring around 10 to
15 inches diameter (25 to 43 cm). These are hand-packed with their largest
dimension vertical and placed directly on the earth.
· Washed gravel or stones screened to a regular size are spread over the
base stones to a depth of 2 inches (5 cm) and packed down using a rammer or
maul.
· A coating of clay is sometimes laid over the stones to seal the road
against water penetration.
· A wearing surface of fine screenings or gravel is laid over the surface.
This is intended to be renewed as it wears away from use or weather.
· Drainage ditches are dug on both sides of the road to take the water away
from the foundations.
The main alternative to Telford's System, was devised by his contemporary
John MacAdam. Macadamised roads involve laying progressively smaller
screened stones over a raised and cambered earth bed. Drainage was also
important. Two inch diameter broken stone was laid to a depth of 10 inches
and tamped down a wearing surface was created by the effect of metal tyres
on wagons and horses hooves grinding the stones down. No clay or other
binding agent were allowed to be used.

some confusion exists between MacAdam's own system and "tarmac" - Tar
MacAdam, the latter being a description of the various forms of more modern
bitumen or asphalt sealed roads. The first use of tar as a sealant against
dust may go back to the 1870s, however, development of bitumous agregate as
a road surface probably only developped with the popularity of rubber tyred
motor vehicles from the early 20th century.

Gary Vines