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An Encyclopedia of the History of Technology part 99 potx

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962
oil-pressure systems for automobile braking and many other power-
transmission applications.
Another form of power-transmission which has made a contribution to public
services has been compressed air. Pneumatic devices in the shape of bellows have
been familiar to craftsmen from antiquity, but little general use was made of
them until the twentieth century, when they became very valuable tools in the
construction industry and in mining, and in various forms of machine tool.
They have also provided an essential part of the modern jet engine in aircraft,
and they have become familiar to motorists the world over as a means of
inflating pneumatic tyres. They have been particularly valuable in deep-mining
processes because they do not cause pollution of the air supply and they
minimize the danger of accidents from sparking or short-circuiting. The facility
for transmitting power over long distances through flexible hosing has made
pneumatic power convenient for many heavy but portable tools such as the drills
used in constructional work. With a compressor coupled to a small diesel engine,
air-powered drills have become a familiar feature of modern roadworks, As with
hydraulic systems, the compressed medium is used to drive a piston or a ram
which can then deliver a reciprocating action or which can be readily converted
to rotary movement. It is less suited than hydraulic power to large-scale
applications and has not been popular for municipal public services, but a system
of underground compressed air pipes was installed in Paris in the 1880s,
carrying power to pneumatic devices in various parts of the city.
WASTE DISPOSAL
Modern life generates many forms of waste, and important public services are
devoted to disposing of them. The water-borne removal of organic waste has
already been considered, because this is so closely related to the provision of a
constant supply of fresh water. Other forms of waste removal can be more
episodic. Thus, industrial and domestic garbage is collected regularly in modern
towns and subjected to various forms of processing to recover metals, glass, and


other reusable materials. The remainder is usually pulverized and compacted
before being disposed of by emptying into holes such as those left by old
quarrying operations, or dumped from barges into river estuaries from which it
can be dispersed by the movement of the tides. A few of the most progressive
public authorities in Sweden and elsewhere have installed the expensive plant
necessary to burn such garbage, using it as a fuel to heat water and generate
power. There is little doubt that this is the most desirable solution to the problem
posed by the disposal of constantly growing masses of rubbish, after everything
of commercial value has been extracted from it, but the heavy initial costs are a
formidable deterrent, tempting authorities to seek cheaper, if less satisfactory,
solutions. It should also be admitted that even the best incinerators of this type
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963
are known to produce dangerous fumes, so this method of disposal is not
problem-free.
Other forms of waste such as those produced by many modern industrial
plants pose even more serious problems of disposal. Some of them, like the waste
from nuclear energy installations and certain chemical works, can present
considerable health hazards. Normally, the producers are prevented from
emitting these effluents into the air and local rivers by legislative controls, but
these are not always adequate and in some cases insufficient to prevent serious
accidents with which neighbours to nuclear power stations and large chemical
works have had to cope. The maintenance of surveillance in these situations is
an important public service, and modern technological equipment such as that
used for monitoring the presence of radioactive materials and for protecting
personnel against dangerous materials, performs a vital part of this service.
ROADS AND POSTAL SERVICES
Amongst those secondary services which, although not basic to the existence
of civilized social life, go far towards making it more pleasant and satisfactory,
the provision of good roads and a postal system are very important. Towns can

function without properly surfaced roads and pavements, but the volume of
urban traffic makes such improvements desirable at an early stage of town
development, and corresponding improvements in roads to neighbouring
districts and places further afield provides immediate benefits in terms of
communications, so that the efficiency of a postal system is closely related to
the condition of the roads. The pressure to improve urban roads came from
local residents anxious to protect their property, and resulted in the paving of
market places and the surfacing of roads with cobbles or granite setts. The
condition of inter-urban roads was not susceptible to the same imperatives for
improvement, although it was occasionally subject to military contingencies
such as led to the construction of sound main routes between Paris and the
frontiers of France, and to the military roads built by General Wade in the
1720s to pacify the Highlands of Scotland. Elsewhere, they were usually left to
the inefficient care of local authorities with little incentive and scant resources
to undertake substantial road improvement.
Industrialization brought both an increase in traffic, which caused more
rapid deterioration of inadequate roads, and a new determination to improve
the roads, stimulated in part by the need for a more efficient postal service. In
Britain, this conjunction of means and needs produced a vigorous programme
of road improvement in the second half of the eighteenth century, carried out
mainly by Turnpike Trusts which sought increasingly effective professional
advice from road builders like John Loudon Me Adam and his family. The
many miles of improved ‘macadamized’ road which resulted involved a fairly
PART FIVE: TECHNOLOGY AND SOCIETY
964
simple technology discussed in Chapter 8. Stage coaches were quick to take
advantage of the improvements and which served, amongst other things, to
extend and accelerate the mail services. Stages coaches were first used in place
of mounted post-boys for British mail services in 1784, and by the 1830s these
vehicles were able to average ten miles an hour over long distances, providing

prompt deliveries of mail in most parts of the country. Later improvements
became necessary in the roads with the advent of motor vehicles and the
pneumatic tyre, because the latter tended to reduce the macadamized surfaces
to dust with a consequent alarming increase in the rate of decomposition of the
roads. The solutions to this problem, first by tar-spraying and then by the
development of highly resilient tarmac and asphalt surfaces, supplemented in
some places by concrete, restored the road system and were generally adopted
both in the towns, where the old-established cobbled streets tended to
disappear, and on the inter-city highways.
Postal services have taken advantage of successive improvements in transport
technology, readily adopting the railways, often with the provision of special
sorting coaches and other equipment, and then accepting the facility for rapid
transit over long distances to all parts of the world offered by regular air-line
services. Otherwise, however, they do not involve very sophisticated
technological equipment, or at least they have not done so until the recent
introduction of electronic devices for scanning and sorting letters. The
introduction of Rowland Hill’s ‘penny post’ in 1840 brought a great increase in
the volume of mail handled by the postal services and the use of adhesive stamps
created a need for perforating machines, making it easier to distribute stamps.
Franking machines, used to cancel the stamps and to register the time and place
of postage were also adopted, and letter boxes were introduced to facilitate the
collection of mail, considerable thought being given to the manufacture of a safe
receptacle, resulting in the cast-iron pillar box bearing the Royal monogram
which, in a succession of forms, has become a traditional feature of the British
postal service. More recently, the introduction of air-mail, area-coding, automatic
sorting devices, pre-paid stamping machines, and optical character readers
(OCR) (see Chapter 15) designed to read key elements in the address and thus
accelerate the sorting process, have all helped to cope with an increasing volume
of postal communications. Only the last of these involve a high degree of
electronic sophistication, and for the most part postal services all over the world

remain heavily dependent on human labour. They have, nevertheless, achieved a
remarkably efficient standard of handling the mail.
TELEGRAPH AND TELEPHONE SERVICES
Most countries have assumed responsibility for operating their postal services
as some form of public corporation, and many countries have extended this
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965
measure of state control to their telegraph and telephone services, although
virtually all of these began as private enterprise ventures and in some countries
they have remained such. The electric telegraph began in Britain in 1837 as
the result of an invention by William Cooke and Charles Wheatstone, who
succeeded in transmitting an electric signal along a wire and registering its
reception with a deflecting needle on a dial (see p. 714). This system was
adopted in the following year in Britain by the Great Western Railway in order
to operate its signalling system, for which purpose it became indispensable to
the railways in their great mid-century boom because it allowed distant signal
boxes to keep in contact with each other. Samuel Morse meanwhile promoted
his own system with its characteristic code of dots and dashes in the United
States, and the network built up by him under the terms of the Morse Bill in
1843 played a vital part in the westward expansion of American settlement.
The establishment of a cable across the English Channel in 1851 put the
business communities of Paris and London into instantaneous contact with
each other and demonstrated the practicability of submarine cables. Several
attempts were made to lay a trans-Atlantic cable before the S.S. Great Eastern
was successful in doing so in 1866, and thereafter other cables were quickly
prepared to bring the advanced societies of the world into telegraphic contact.
The achievement of this objective was signalled in 1872 when the Mayor of
Adelaide in South Australia exchanged telegraph greetings with the Lord
Mayor of London.
The telephone was invented in America in 1876 by A.G.Bell, but it made

little progress until two years later when D.E.Hughes invented the
electromagnetic microphone which, when added to the telephone, amplified
the weak voice currents produced in Bell’s device and thus made it suitable for
long-distance communication (see p. 719). As such, the telephone was eagerly
adopted by the American business community, and after a slower start it
became a universal tool of business and domestic communication in Europe
also. The first British telephone company was formed in 1878, and soon
afterwards telephone exchanges were established in all the main towns and
cities of the country and inter-city lines were constructed. By 1884, there were
11,000 ‘telephone stations’ (i.e. offices and homes with telephones) in Britain,
while the United States at the same time had 148,000. As with the
development of the telegraph system, British telephony was pioneered by
private companies and then taken over by the General Post Office and
conducted virtually as a government monopoly. The telegraph network had
been taken over in 1868, and by 1912 most of the telephone network had been
similarly acquired. By 1958, the GPO was responsible for about 7 million
telephones, amounting to about one for every seven inhabitants of Britain,
which compared with 67 million telephones in the USA, giving about one for
every two-and-a-half inhabitants. Technologically, the telephone service has
continued to improve, with automatic exchanges, trunk dialling schemes, a
PART FIVE: TECHNOLOGY AND SOCIETY
966
trans-Atlantic telephone cable carrying 35 channels which was opened in 1956,
and now the ever-expanding facility for satellite links through telephone
stations in synchronous orbits round the Earth which has brought the whole of
the planet within the scope of instantaneous voice communication. This has
been a technological revolution of tremendous significance, and has provided
an outstanding public service.
CONCLUSION
In several of the public services considered in this chapter, it is important to

remember the contribution made in the past 25 years by electronic devices and
especially by computers. These ubiquitous innovations of modern technology
have made themselves indispensable in many aspects of industrial
manufacturing, commerce, transport and communications. It is not surprising,
therefore, to find them widely adopted in the public utilities like gas and
electricity supply (though less obviously in water undertakings, which still
impress mainly by their civil engineering works).
These valuable products of modern high technology should not be taken
for granted. A sophisticated technology underpins all the basic services which
the citizen of modern megalopolis has come to rely upon with remarkable
confidence. Consternation is complete when there is a serious breakdown in
the system, so that the lights go out, the elevators stop working and the water
dries up in the taps. In such circumstances, an awareness of the complexities
and interdependence of modern technologies is at least an aid to peace of mind
and, at best, a help towards working out the solution to the problem.
There are, of course, other problems associated with many of the
technologies employed in the public services in addition to the possibility of
outright failure. Air and noise pollution, for instance, are insidious facts of
modern town life; acid rain derives from our thoughtless consumption of
carbon fuels; the urban environment tends to become spiritually and culturally
restrictive. But without ignoring these problems, it is salutary to recognize the
enormous service of technology to the community in the shape of the public
services, and, while trying to eliminate harmful by-products and side-effects, to
seek their extension to communities which at present do not enjoy their
benefits. It is important, in short, to envisage a goal whereby the sort of public
services at present enjoyed by citizens of developed nations are made available
to everybody.

967
21


WEAPONS AND ARMOUR

CHARLES MESSENGER
PREHISTORIC WEAPONS
Among the earliest and most widespread of man’s weapons is the spear.
Originally it was merely a wooden pole with one end sharpened with a stone
or piece of bone, but once palaeolithic man had discovered fire, some 500,000
years ago, charring was also used to harden and sharpen the tip. The next
stage was to insert pieces of stone or bone in order to reinforce the point, and
then to fit a stone head. From a very early period there were two types of
spear, thrusting and throwing. The throwing spear, or javelin, tended to be
lighter and in order to increase its range a device called the spear thrower was
introduced. This acted as a lever and was a piece of shaped wood, bone or
horn with a hook or recess into which the end of the spear fitted.
Two of man’s other original weapons are the club and the axe. The club
was originally made of hardwood, the head being larger than the handle. Like
the tip of the spear, the head was then reinforced with stone. The original axe
was made entirely of stone, simply an almond-shaped head sharpened by
flaking. In about 3500 BC the wooden haft or handle was introduced, being
attached to the stone head by means of bent wood, horn sockets, lashing and
gum. Then, during the neolithic or New Stone Age era, 7000–2000 BC, the art
of grinding, polishing and drilling of stone was developed, which radically
increased the effectiveness of the axe, both as a tool and as a weapon of war.
The head was now often fitted to the handle by means of a circular hole drilled
through it, known as the ‘eye’.
Perhaps surprisingly, the bow was already in existence around 15000 BC. It
was first developed by the Mediterranean civilizations, and was taken up in
northern Europe during the ninth millennium. From the start, yew, because of
its good tensile characteristics, was the preferred wood, although in colder

climates, where yew did not grow, elm and occasionally pine were used. Most
bows were man-sized, and by the third millennium the composite bow,
PART FIVE: TECHNOLOGY AND SOCIETY
968
strengthened with horn and sinews, was in use in some regions. The string
was normally made with plaited leather strips. Stone arrowheads were used,
and the arrow itself was straightened by passing it through a hole drilled in
bone or horn. In order to obtain arrows of standard size—important in terms of
accuracy—they were shaved by means of a hollow tube cut as grooves in a split
stone. The other basic weapon was the slingshot, a spherically shaped stone
which was projected from a leather sling, which the firer whirled above his
head in a circular motion in order to impart increased velocity to the stone.
THE BRONZE AGE AND CLASSICAL ERA
As with much else in the history of technology, the discovery of metal and the
coming of the Bronze Age in about 2000 BC had a dramatic impact on
weapons. The development of the forced-draught furnace, in particular,
enabled the known ores to be smelted and to be fashioned into shapes that
could not be achieved, or at least only with much difficulty, by the stone
craftsman. Furthermore, damaged metal weapons could be recycled. An added
advantage was that much longer cutting and thrusting weapons could be
made. Daggers had existed in stone, but, using bronze and copper, the sword
could now be made. Both these metals are, however, relatively soft, and in
order to make a more durable weapon, which would not bend easily, the metal
was strengthened by hammering, then by the addition of lead at the smelting
stage (see Chapter 1). Initially, the sword was merely a thrusting weapon, with
a strong central rib running down the centre of the blade and smaller side ribs,
but gradually a cutting capability was introduced, with double cutting edges.
With the discovery of iron, around 1000 BC, weapons became much tougher,
but it was a much more difficult metal to work than copper and bronze, and
hence for a long time the three coexisted.

The growing effectiveness of weapons in their ability to kill and maim
caused increasing attention to be paid to personal protection. The original
form of armour, consisting of layers of linen wrapped round the body, was
used by the Egyptians in the third millennium. Hide was also used and
gradually metal strips were introduced; the Sumerians in Mesopotamia had
long cloaks reinforced with metal discs during the first half of the third
millennium BC. Two basic types of early armour were scaled and lamellar.
The former consisted of a short tunic on which were sewn overlapping bronze
scales, while lamellar armour had pliable metal plates, or lames, which were
laced together in slightly overlapping horizontal rows. Later, in about the 5th
century BC, chain mail was developed by interlinking metal rings, or
sometimes wire. Like body armour, helmets were originally made of cloth, but
this gave way to leather, metal, or a mixture of the two. Apart from the basic
conical style, helmets with cheek pieces to protect the face from sword cuts
WEAPONS AND ARMOUR
969
became popular. Often they were elaborately decorated, including horns and
crests, not merely from male vanity but more to make the wearer look
imposing and formidable in the eyes of his enemies.
The third major item of personal protection was the shield, which was
certainly in common use by the beginning of the second millennium BC.
Shields existed in several different shapes—round, rectangular and oval—and
were made of leather, leather-covered wood and wickerwork. They also often
had overlaid thin strips of metal which were used both decoratively and to
provide additional protection.
Before 1000 BC the main centre for both military and political development
was bound by the three major rivers of the Middle East, the Nile, Euphrates
and Tigris, with the two dominant countries being Mesopotamia and Egypt.
From about 3500 BC the dominant weapon in Mesopotamia was the chariot,
which gave warfare much greater momentum and punch than hitherto.

Originally it was drawn by asses, until the horse arrived from the steppes of
Mongolia around 2000 BC. Chariots were used to make frontal charges on the
enemy in order to create panic, their crews being equipped with both javelins,
to engage at medium range, and spears for hand-to-hand fighting. By 1500
BC, with the development of the spoked wheel, means were found to make the
chariot lighter and hence more mobile, thus increasing its effectiveness as a
weapon of shock action. Surprisingly, the Egyptians did not use the chariot
until about 1600 BC, but it quickly became the basis of their military might.
Armed also with the double convex shaped composite light bow, with a range
of 275–365m (1200–1600ft), which they used both mounted in their chariots
and on foot, they became a formidable force. Indeed, it was the arrow
projected by the light composite bow, with its reed shaft and bronze head,
which brought about the need to consider personal protection.
It was not until the rise of the Assyrians at the end of the second
millennium BC that horse cavalry began to appear, and then in only a
secondary role on the battlefield, being used to harry the enemy’s flanks, while
the chariot remained the decisive weapon. Early cavalry were armed with both
bows and spears, but their horses had merely a bridle, with no stirrups.
So formidable was the Assyrian army that opposing forces would not take
to the field against it if they could avoid it. Instead they relied on the protection
of the fortified city, a concept which had been in existence since the third
millennium. An example is the fortress of Megiddo, which was built at the
beginning of the nineteenth century BC. The base of its main wall was 2.13m
(7ft) and it had 5.5m (18ft) salients and recesses, with a crenellated parapet on
top. To counter these strong defences the Assyrians introduced battering rams
designed to break down the main gates to the city. They were mounted in
wooden towers, which were roofed and protected by metal plates, and were
borne on six wheels. Under the roof was a platform used by archers to shoot
at the defenders on the walls. Tunnelling and scaling ladders were also used.
PART FIVE: TECHNOLOGY AND SOCIETY

970
By 500 BC, the Greeks had become the major military power and they
made two significant contributions to the history of warfare. The first was
the phalanx, a close order formation made up of hoplites, infantry equipped
with 2.44m (8ft) spears and swords and dressed in horsehair-plumed
helmets, breastplates and calf and shin plates known as greaves, with a
0.91m (3ft) diameter round shield held on the left arm. This tightly packed
‘mobile fortress’ was frequently more than a match for looser and less well
disciplined bodies of enemy. The other development engineered by the
Greeks was the invention of torsion artillery, in the shape of the catapult. It
was the Alexandrian mathematicians who developed the theory of the
catapult, showing how there was a direct correlation between the proportions
of the various parts and the diameter of the ‘straining hole’ through which
the skeins which controlled the tension passed, and the Greeks who put it
into practice. They had two types of catapult (or ballista, as the Romans were
to call it). The katapeltes were used to project arrows, javelins and smaller
stones—a 3.63kg (8lb) stone could be projected accurately to a range of 228m
(750ft)—while the larger petrobolos could hurl stones of up to 25kg (55lb) in
weight. The skeins themselves were made of twisted human hair and sinew.
A further refinement was the use of fire arrows, either with their heads
wrapped in inflammable material and ignited just before firing, or made red
hot by heating in coal fires.
Unlike the Greeks, the Romans were not innovators but very practical
engineers, who applied the ideas of their predecessors. Perhaps their most
outstanding feats of engineering were the numerous aqueducts which are still
to be seen today. The Romans have been called ‘the greatest entrenching army
in history’ and it was a constant principle that when legions halted after a day’s
march they constructed a fortified camp, usually square in shape, with
ramparts, palisades and ditches. Apart from the comfort afforded, it also meant
that they always had a secure base from which to operate. Roman camps,

especially those near rivers, are the foundation of many of today’s European
towns and cities. As with the Greeks, the main element was the regular
infantry of the legions, whose members were armed with a short stabbing
sword, javelins and spears. The main shield used as the scutum, large and semi-
cylindrical rectangular in shape, which when rested on the ground would come
up to a man’s chest. With this shield they went one stage further than the
mobile phalanx of the Greek hoplite by developing the testudo or tortoise,
especially useful in sieges. While the outside ranks protected the front and
flanks with their shields, those on the inside put theirs over their heads in order
to provide protection from arrows and missiles fired from above. Cavalry still
played a secondary role and, indeed, the Romans tended to rely on
mercenaries or ‘auxiliaries’ to provide it as well as their archers and slingers.
One new weapon of war introduced was the elephant. The Greeks had used it
as heavy cavalry, but it was the Carthaginians who brought it to the fore at the
WEAPONS AND ARMOUR
971
end of the third century BC, and their celebrated general Hannibal took
elephants on his march across the Alps which led to defeat of the Romans at
Cannae in 216 BC. The Romans finally gained their revenge at Zama in 202
BC by using trumpets to panic and stampede the beasts.
THE DARK AGES
By 400 AD the Roman Empire was beginning to disintegrate in the face of
Vandals, Goths and then Huns from the east. These races relied almost
entirely on the horse, and they brought with them the stirrup, which was
responsible more than anything else for the gradual elevation of cavalry to the
decisive arm on the battlefield. Stirrups gave the rider the necessary stability to
withstand the shock of the charge and meant that cavalry could now be
committed against the main force of the enemy rather than merely harrying his
flanks and being used in the pursuit. This, combined with brilliant
horsemanship and the hardiness of their mounts, which could travel up to

160km (100 miles) a day, as well as the use of mounted archers en masse, made
the Huns especially a devastating military power.
One relic of the Roman Empire in south-eastern Europe became the
Byzantine Empire, which successfully withstood the ravages of Huns, Arabs,
Turks and Magyars for five centuries before succumbing to the Turks at the
Battle of Manzikert in AD 1071. The Byzantines built their armies around the
cavalryman, having taken the Hun model to heart. He was dressed in a long
chain-mail shirt down to his thighs with steel helmet, gauntlets and shoes and
was armed with a heavy broadsword, dagger, short bow and lance. His horse
had a saddle and iron stirrups and was sometimes protected by a poitrel or
breastplate. There were two types of Byzantine infantry, light, which mainly
consisted of archers, and heavy, armed with lance, sword and axe. In battle
they held their ground while the cavalry achieved victory through repeated
charges at the enemy.
During this period the first chemical weapon made its appearance. This was
Greek Fire, which was certainly used by the Byzantine defenders of
Constantinople during some of its numerous sieges in the seventh and eighth
centuries. It was, in essence, liquid fire and a forerunner of today’s napalm. No
precise recipe for making it exists, but the main ingredients were sulphur, pitch,
nitre and petroleum, which were boiled together. It was effective on both land
and sea and appears to have been used in siphons or as a grenade made of
glass or pottery. During sieges it was often delivered by means of ballistae.
The equivalent to the Byzantine Empire in the west was that of the Franks.
Initially they were reliant on infantry, which was only lightly armoured and
armed with axes and barbed javelins, used as both throwing and thrusting
weapons. The axe, which was rather like the Red Indian tomahawk, was an

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