[1] The illustrations in this article are from Prof. G. Lunge's _Coal
Tar and Ammonia_, by permission of Friedrich Vieweg u. Sohn.
COALVILLE, a town in the Loughborough parliamentary division of
Leicestershire, England, 112 m. N.N.W. from London. Pop. of urban
district (1901) 15,281. It is served by the Midland railway, and there
is also a station (Coalville East) on the Nuneaton-Loughborough branch
of the London & North-Western railway. This is a town of modern growth,
a centre of the coal-mining district of north Leicestershire. There are
also iron foundries and brick-works. A mile north of Coalville is
Whitwick, with remains of a castle of Norman date, while to the north
again are slight remains of the nunnery of Gracedieu, founded in 1240,
where, after its dissolution, Francis Beaumont, the poet-colleague of
John Fletcher, was born about 1586. In the neighbourhood is the Trappist
abbey of Mount St Bernard, founded in 1835, possessing a large domain,
with buildings completed from the designs of A. W. Pugin in 1844.
COAST (from Lat. _costa_, a rib, side), the part of the land which meets
the sea in a line of more or less regular form. The word is sometimes
applied to the bank of a river or lake, and sometimes to a region (cf.
Gold Coast, Coromandel Coast) which may include the hinterland. If the
coast-line runs parallel to a mountain range, such as the Andes, it has
usually a more regular form than when, as in the _rias_ coast of west
Brittany, it crosses the crustal folds. Again, a recently elevated coast
is more regular than one that has been long exposed to wave action. A
recently depressed coast will show the irregularities that were
impressed upon the surface before submergence. Wave erosion and the
action of marine currents are the chief agents in coast sculpture. A
coast of homogeneous rock exposed to similar action will present a
regular outline, but if exposed to differential action it will be
embayed where that action is greatest. A coast consisting of rocks of
unequal hardness or of unequal structure will present headlands,
"stacks" and "needles" of hard rocks, and bays of softer or more loosely
aggregated rocks, when the wave and current action is similar
throughout. The southern shore-line of the Isle of Wight and the western
coast of Wales are simple examples of this differential resistance. In
time the coast becomes "mature" and its outline undergoes little change
as it gradually recedes, for the hard rock being now more exposed is
worn away faster, but the softer rock more slowly because it is
protected in the bays and re-entrants.
COAST DEFENCE, a general term for the military and naval protection and
defence of a coast-line, harbours, dockyards, coaling-stations, &c.,
against serious attack by a strong naval force of the enemy,
bombardment, torpedo boat or destroyer raids, hostile landing parties,
or invasion by a large or small army. The principal means employed by
the defender to cope with these and other forms of attack which may be
expected in time of war or political crisis are described below. See
also for further details NAVY; ARMY; FORTIFICATION AND SIEGE-CRAFT;
AMMUNITION; ORDNANCE; SUBMARINE MINES; TORPEDO. The following is a
general description of modern coast defences as applied in the British
service.
No system of coast defence is of any value which does not take full
account of the general distribution of sea-power and the resultant
strength of the possible hostile forces. By resultant strength is meant
the balance of one side over the other, for it is now generally regarded
as an axiom that two opposing fleets must make their main effort in
seeking one another, and that the force available for attack on coast
defences will be either composed of such ships as can be spared from the
main engagement, or the remnant of the hostile fleet after it has been
victorious in a general action.
Coast defences are thus the complement and to some extent the measure of
naval strength. It is often assumed that this principle was neglected in
the large scheme of fortification associated in England with the name of
Lord Palmerston, but it is at least arguable that the engineers
responsible for the details of this scheme were dependent then as now on
the naval view of what was a suitable naval strength. Public opinion has
since been educated to a better appreciation of the necessity for a
strong navy, and, as the British navy has increased, the scale of coast
defences required has necessarily waned. Such a change of opinion is
always gradual, and it is difficult to name an exact date on which it
may be said that modern coast defence, as practised by British
engineers, first began.
An approximation may, however, be made by taking the bombardment of
Alexandria (1881) as being the parting of the ways between the old and
the modern school. At that time the British navy, and in fact all other
navies, had not really emerged from the stage of the wooden battleships.
Guns were still muzzle-loaders, arranged mainly in broadsides, and
protected by heavy armour; sails were still used as means of propulsion;
torpedoes, net defence, signalling, and search-lights quite undeveloped.
At this time coast defences bore a close resemblance to the ships--the
guns were muzzle-loaders, arranged in long batteries like a broadside,
often in two tiers. The improvement of rifled ordnance had called for
increased protection, and this was found first by solid constructions of
granite, and latterly by massive iron fronts. Examples of these remain
in Garrison Fort, Sheerness, and in Hurst Castle at the west end of the
Solent. The range of guns being then relatively short, it was necessary
to place forts at fairly close intervals, and where the channels to be
defended could not be spanned from the shore, massive structures with
two or even three tiers of guns, placed as close as on board ship and
behind heavy armour, were built up from the ocean bed. On both sides the
calibre and weight of guns were increasing, till the enormous sizes of
80 and 100 tons were used both ashore and afloat.
The bombardment of Alexandria established two new principles, or new
applications of old principles, by showing the value of concealment and
dispersion in reducing the effect of the fire of the fleet. On the old
system, two ships firing at one another or ships firing at an
iron-fronted fort shot "mainly into the brown"; if they missed the gun
aimed at, one to the right or left was likely to be hit; if they missed
the water-line, the upper works were in danger. At Alexandria, however,
the Egyptian guns were scattered over a long line of shore, and it was
soon found that with the guns and gunners available, hits could only be
obtained by running in to short range and dealing with one gun at a
time.
This new principle was not at once recognized, for systems die hard,
and much money and brains were invested in the then existing system. But
a modern school was gradually formed; a small group of engineer officers
under the headship of Sir Andrew Clarke, the then inspector-general of
fortifications, took the matter up, and by degrees the new views
prevailed and the modern school of coast defence came into being between
1881 and 1885. Meanwhile important changes had been developing in the
gun, the all-important weapon of coast defence, changes due mainly to
the gradual supersession of the muzzle-loader by the breech-loader. The
latter gave the advantages of quicker loading and more protection for
the gun detachment over and above the technical improvements in the gun
itself, which gave higher muzzle velocity, greater striking effect and
longer effective range.
All this reacted on the general scheme of coast defence by enabling the
number of guns to be reduced and the distance between forts increased.
On the other hand, the ships, too, gained increased range and increased
accuracy of fire, so that it became necessary in many cases to advance
the general line of the coast defences farther from the harbour or
dockyard to be defended, in order to keep the attackers out of range of
the objective.
Another change resulted from an improvement in the method of mounting.
Even in the older days discussion had arisen freely on the relative
merits of barbette and casemate mounting. In the former the gun fires
over a parapet, giving a larger field of view to the gun-layer, and a
larger field of fire for the gun, with, however, more exposure for the
detachment. The latter gives a restricted view and greater safety to the
layer, but unless the casemate takes the form of a revolving turret, the
arc of fire is very limited.
An important advantage of the barbette system is its cheapness, and thus
in order to obtain with it concealment, suggestions were made for
various forms of mounting which would allow of the gun, under the shock
of recoil, disappearing behind the parapet to emerge only when loaded
and ready for the next round. A mounting of this description for
muzzle-loading guns, designed by Colonel Moncrieff, was actually in use
in the defences of Alexandria and in H.M.S. "Temeraire."
But with the increased charges and length of breech-loading guns, a
further change was desirable, and after some trials a system of
disappearing mountings (see Ordnance: _Garrison Mountings_) was adopted
into the British service.
A word must be now said on the size of gun finally adopted. At first
muzzle-loaders figured largely in the British defences, even though
these were planned on modern ideas; and even in 1906 muzzle-loading guns
still existed and were counted as part of the defences. The sizes of
these guns varied from the 32- or 64-pounder, of which the nomenclature
depends on the weight of the shell, to the 7-in., 9-in., 10-in., 11-in.,
12.5- and finally 17.25-in., the size indicating the calibre. Such a
multiplication of sizes was due to gradual improvements in the science
of gun manufacture, each advance being hailed as the last word to be
said on the subject, and each in turn being rapidly made obsolete by
something bigger and better. But with the improvements in gun design
which followed the introduction of breech-loaders, the types used in
coast defence were gradually narrowed down to two, the 9.2-in. and the
6-in. guns. Of these, the 9.2-in. was considered powerful enough to
attack armour at any practical range, while the 6-in. gun was introduced
to deal with lightly armed vessels at shorter ranges where 9.2-in. guns
were unnecessarily powerful.
A few larger guns of 10-in. calibre have actually been used, but though
the British navy has now sealed a 12-in. 50-ton gun as the stock size
for battleships, for the heavy armament of the coast defences the War
Office remain faithful to the 9.2-in. calibre, preferring to develop
improvements rather in the direction of more rapid fire and higher
muzzle velocity.
The 6-in. has also been retained and is extensively used for the smaller
ports, where attack by powerful vessels is for various reasons
considered improbable.
The design of the forts to contain the guns necessarily varied with the
type of defence adopted, and the duties which the forts had to fulfil.
These duties may be said to be twofold, first to facilitate the service
of the guns, and secondly to protect the guns and their detachments from
damage by fire from ships, or by close attack from landing parties. The
service of the gun is provided for by a system of cartridge and shell
magazines (see AMMUNITION), well protected from fire and suitably
arranged. The shelters for the gun detachments must be bomb-proof and
fitted with some arrangements for comfort and sanitation. Formerly it
was the custom to provide living accommodation for the full garrison in
casemates inside each fort, but it is now considered better to provide
barrack accommodation in the vicinity and to occupy forts in peace only
by a few caretakers. The shelters in the fort itself can thus be kept at
the minimum required when actually manning the guns. The protection of
the guns and magazines against bombardment is provided, in the British
service, mainly by an earthen parapet over a substantial roof or wall of
concrete, but immediately round the gun an "apron" of concrete is
necessary to withstand the shock of discharge or "blast."
It has been already mentioned that in the old designs a large number of
guns was put in each fort, but with dispersion and improved gun power
this number was much reduced. At first the type of fort adopted was for
four guns, of which the two in the centre were heavy and the two on the
flank of medium power. Such a design was good from the point of view of
the engineer; it gave an economical grouping of magazines and shelters
and was easily adapted to varying sites, and the smaller guns helped the
larger by covering their flanks both towards the sea and also over the
land approaches. But from the point of view of the artillery officer the
arrangement was faulty, for when the guns are too much separated,
ranging has to be carried out separately for each gun. On the other
hand, two guns of the same calibre placed near one another can be fought
simultaneously and form what is known as a "group." In the typical 4-gun
battery described above, the flank guns had to be fought independently,
which was wasteful of officers and staff. Further, in a battery of more
than two guns the arc of fire of the centre guns is much restricted by
that of the guns on either flank.
For these reasons it is now generally recognized that new works should
be designed for only two guns of the same calibre, though 3- or 4-gun
batteries are occasionally used in special circumstances.
Protection of the gun detachments against infantry attack is best
provided by a line of infantry posts outside and on the flanks of the
gun batteries, but as small parties may evade the outposts, or the
latter may be driven in, it is necessary to place round each fort a line
of obstacles sufficient to protect the guns against a rush and to cover
the infantry while it rallies. This obstacle was formerly a wet or dry
ditch, with escarp, counterscarp and flanking galleries; but with the
new design of parapet a simpler form of obstacle was adopted. This was
obtained by carrying down and forward the slope of the parapet to a
point well below the level of the surrounding ground, and then placing a
stout fence at the foot of the parapet and concealed from view. It is in
fact the old principle of the sunk fence, and has this further
advantage, that the fence, being visible from the parapet, can be kept
under fire by men posted between the guns without any special flanking
galleries.
Occasionally two or more batteries are placed inside one line of
obstacles, but usually each 2-gun battery is complete in itself.
Cases arise, e.g. with sites on the top of a cliff, where no obstacle is
required; in such places the parapet merges into the surrounding ground.
In old days the parapet was shaped with well-defined edges and slopes.
Now the parapet slopes gently down to the front and is rounded at the
sides, so as to present no definite edge or angle to the enemy, and
concealment is furthered by allowing grass or small scrub to grow over
the parapet and round the guns. In order to obtain complete concealment
from view the background behind the guns must be carefully studied from
the point of view of the attack. Sites on the sky-line, and marked
contrasts of colour or shape, should be avoided. In some cases extensive
planting, amounting to landscape gardening, is justified. This is most
easily arranged in the tropics, where plant growth is rapid. In all
cases the guns and their mountings should be coloured to blend with the
background and thus avoid hard lines and shadows.
Any change of principle such as that of 1885 involves improvements both
in guns and their adjuncts. Of these latter the most important was the
position-finder designed by Colonel Watkin. This instrument in its
simplest form, when the observer is following a ship through the
telescope of the instrument, draws on a chart the track of the ship, so
that the exact bearing and distance of the latter can be ascertained at
any time and communicated to the guns by electrical and other dials, &c.
The position-finder may be some distance from the guns it serves, and
connected with them by electric cable. The guns can then be placed well
under cover and in many cases out of sight of the target, giving a
measure of protection which cannot be obtained with any system of direct
laying over sights. This instrument has been applied on a high site to
control guns placed low, or where guns are so placed as to be liable to
obscuration by fog or mist the position-finder can be placed below the
fog-line. In either case direct laying is provided for as an
alternative. In some defences batteries equipped with old pattern 9-in.
muzzle-loading guns, mounted as howitzers for long-range firing, have
been placed in folds in the ground so as to be quite invisible from the
sea and therefore invulnerable. Such batteries are fought entirely by
the position-finder.
The next adjunct to coast defences is the submarine mine. In Great
Britain the first submarine mining company dates from 1873, and from
that date mining defences were gradually installed both at home and
abroad; but the modern system of mining, which for twenty years was
maintained at British ports, really started into full life under the
impetus of Sir A. Clarke, about the same year (1885) in which we have
dated the commencement of the modern coast defence system.
With the increased speed of warships, a method of attack on
fortifications was evolved by running past the main defences and either
taking them in reverse, or disregarding them and attacking the dockyard
or other objective at short range. This was made more possible at most
defended ports by the pushing forward of the defences which has been
already alluded to, and it is especially dangerous where dockyards or
towns are situated some way up a river or estuary, so that once the
defences are passed there is a large stretch of water (e.g. the Thames,
the Solent, and Cork harbour) in which the enemy can manoeuvre. In such
cases there are two possible forms of defence, first by arranging for
gun-fire behind the main gun position, usually called the defence of
inner waters, and secondly by placing in the entrance and under the fire
of the main gun defence some form of obstruction to detain ships under
fire. This obstruction can be _passive_ (booms, chains, rows of piles or
sunken ships) or _active_ (mines or torpedoes). Passive obstructions are
only effective against comparatively small craft, and at important ports
mines are the only efficient obstruction which can be used against large
vessels.
After some years of experiment, English engineers adopted two main
classes of mines, called "observation" and "contact" mines (see
SUBMARINE MINES). Both were fired by electricity, which was applied only
at the moment a hostile ship was within the dangerous zone of a mine. In
the observation mines the moment of applying the electric current was
ascertained by a position-finder, which, tracing a ship's course on a
chart, made an electrical connexion at the moment the ship was over a
mine. These mines were placed so as to be well below the bottom of any
ships afloat and were used in channels which it was desired to leave
open for the entrance of friendly vessels. Contact mines, which are
moored a few feet below the surface of the water, are fired after
certain electrical connexions have been made in a firing room on shore
by the ship itself striking against the mine. These are used in waters
which it is intended to deny to friend and foe. Except in narrow waters
where the whole width of the channel was required for friendly traffic,
contact mines were generally used to limit the width of the channel to
the minimum consistent with the amount of friendly traffic which would
use the port in war. It will be readily understood that by bending this
channel and disclosing its exact position only to special pilots, a very
complete measure of security against surprise would be obtained. In
English ports the practical importance of allowing free ingress for
friendly traffic overruled all other considerations, and the friendly
channels were always straight and coincided with some part of the usual
fairway channel. They were also carefully marked by lightships and
buoys.
A variation of the submarine mine is the Brennan torpedo, purchased by
the British government about 1890. This differs from the torpedo used on
board ship, mainly by the fact that the engine-power which drives it is
on shore and connected with the torpedo by two strong wires. These wires
are wound out of the torpedo by the engine, and by varying the strain on
the two wires very accurate control of the steering can be obtained.
This torpedo shares with the submarine mine the disadvantages that it
must wait for the enemy to venture within its range, and with all other
forms of defence (except contact mines), that it is made useless by fog
or rain. As compared with a mine it has the advantage of being
unaffected by tide or depth, and of forming no obstruction to traffic,
except when actually in action. It was installed at the principal ports
only.
The system of defence hitherto described is thus a main gun defence of
9.2-in. and 6-in. guns pushed well forward, assisted by
position-finders, mine-fields and torpedo stations, and with some gun
defence of inner waters. Subject to improvements in patterns of guns and
mountings--of which the most important has been the substitution of
barbette mounting and shield for the recoil mounting described
above--this system held the field up to 1905, when, partly as a result
of the experience of the Russo-Japanese War, and partly owing to the
alteration of the naval balance of power due to the destruction of the
Russian fleet, both the scale and system of defence were very
considerably modified.
We can now consider another branch of defence, which was evolved _pari
passu_ with the automobile torpedo, and was therefore almost
non-existent in 1885. In this year the boats specially built for
carrying torpedoes were little more than launches, but in the next five
years was developed the type of first-class torpedo boat. This, while
seaworthy, was limited as to its radius of action by the small amount of
coal it would carry. But with a possibly hostile coast only a few hours'
steam away, and with foreign harbours thronged with torpedo craft, it
became necessary for the British government especially to consider this
form of attack and its antidote. It was obvious that in daytime and in
clear weather such an attack would have little chance of success, also
that in no circumstances would torpedo boats be able to damage fixed
defences. Their best chance was attack by night, and the only form of
attack was that referred to above as "running past," that is, an attempt
to evade the defences and to attack ships or docks inside. The light
draught of torpedo boats and their comparative invisibility favoured
this form of attack.
To meet it the first requirement was some form of illumination of the
defended channel. Experiments in the attack and defence of defended
harbours took place at Gosport in 1879 and 1880, at Milford Haven in
1885, at Berehaven (by the royal navy) in 1886, at Langston Harbour in
1887, and a series at the Needles entrance of the Isle of Wight up to
1892. During the course of these experiments various methods of
illumination were tried, but by far the best was found to be the light
from an electric arc-lamp of high power projected by powerful
reflectors. At first these were used as concentrated beams forming a
pencil of light with an angular opening of about 2 deg. to 3 deg. Such
a beam directed at an incoming ship gives effective illumination up to a
mile or more from the source of light, but has the disadvantage that it
must be moved so as to follow the ship's movements. Each beam thus
lights only one ship at a time, and the movements of several beams
crossing and recrossing have a very confusing effect, with the
consequent risk that a proportion of the attacking vessels may slip
through unnoticed.
An alternative method of using electric lights is to arrange the
projector so that the light comes out in a fan (generally of 30 deg.
divergence). Two or three such lights are usually placed side by side,
forming an illuminated fan of considerable divergence. These fans are
now used for the main defence, with in front of them one or more
search-lights to warn the defences of the approach of ships. There is
some loss of range when using these fans as compared with search-lights,
but by occupying both sides of a channel and placing the defences
against torpedo boats at the narrowest point, an effective illumination
can be obtained in moderate weather.
Heavy guns can, of course, be fired against torpedo boats, but their
rate of fire is relatively slow, and at first they had also the
disadvantage of using black powder, the smoke of which obscured the
lights.
A small quick-firing gun using smokeless powder was seen to be a
necessity. At first the 6-pounder was adopted as the stock size
supplemented by machine guns for close range, but soon afterwards it
became necessary to reconsider the scale of anti-torpedo boat defences,
owing first to the increased size of first-class torpedo boats, and
secondly to the introduction of a new type of vessel, the torpedo boat
destroyer. The increased size of torpedo boats, and improved
arrangements for the distribution of coal on board, made these boats
practically proof against 6-pounder guns and necessitated the
introduction of the 12-pounder. The torpedo boat destroyer, originally
introduced to chase and destroy torpedo boats, not only justified its
existence by checking the construction of more torpedo boats, but in
addition became itself a sea-going torpedo craft, and thus increased the
menace to defended ports and also the area over which this form of
attack would be dangerous.
This development was met by an increased number of 12-pounder guns,
assisted in the more important places by 4.7-in. (and latterly 4-in.)
guns, and also by an increased number of lights, both guns and lights
increasing at some places nearly fourfold. But even with the best
possible arrangement of this form of defence, the possibility of
interference by fog, mist or rain introduces a considerable element of
uncertainty.
About the same time, and largely on account of the demand for better and
quicker firing, the "automatic sight" was introduced (see ORDNANCE:
_GARRISON_; and SIGHTS). In this, a development of the principle of the
position-finder, the act of bringing an object into the field of the
auto-sight automatically lays the gun. In order to take full advantage
of this, the ammunition was made up into a cartridge with powder and
shell in one case to allow of the quickest possible loading. It may be
added that the efficiency of the auto-sight depends on the gun being a
certain height above the water, and that therefore the rise and fall of
tide has to be allowed for in setting the sight.
In view of the possible interference by fog it was thought wise at an
early stage to provide, towards the rear of the defences, some form of
physical obstacle behind which ships could lie in safety. Such an
obstacle had been designed in the early days by the Royal Engineers and
took the form of a "boom" of baulks of timber secured by chains. Such
booms were limited in size by considerations of expense and were only
partially successful. About 1892 the British navy took the matter up and
began experiments on a larger scale, substituting wire hawsers for
chains and using old gunboats to divide the booms up into sections of
convenient length. The result was that booms were definitely adopted as
an adjunct of coast defence. Their place is behind the lighted area, but
within reach of some of the anti-torpedo boat batteries.
Other forms of obstacle to torpedo boat attack, based on a modification
of contact mines or a combination of mines and passive obstructions,
have been tried but never definitely adopted, though some form of
under-water defence of this description seems necessary to meet attack
by submarines.
We may now summarize the anti-torpedo boat defences. These are, first,
an outpost or look-out line of electric search-lights, then a main
lighted area composed of fixed lights with which there are a
considerable number of 12-pounder or 4-in. Q.F. guns fitted with
auto-sights, and behind all this, usually at the narrowest part of the
entrance, the boom.
Once coast defences are designed and installed, little change is
possible during an attack, so that the operation of fighting a system of
defence, such as we have considered above, is mainly a matter of peace
training of gun-crews, electric light men and look-outs, coupled with
careful organization. To facilitate the transmission of order and
intelligence, a considerable system of telephonic and other electrical
communication has been established. This may be considered under the
three heads of (1) orders, (2) intelligence, (3) administration.
The communication of _orders_ follows the organization adopted for the
whole fortress. Each fortress is commanded by a fortress commander, who
has a suitable staff. This officer sends orders to commanders of
artillery, engineers, and infantry. The artillery officer in charge of a
group of batteries is called a "fire commander"; his command is
generally confined to such batteries as fire over the same area of water
and can mutually support one another. Thus there may be several fire
commanders at a defended port. Anti-torpedo boat batteries are not in a
fire command, and are connected to the telephone system for intelligence
only and not for orders. The engineers require orders for the control of
electric lights or Brennan torpedo. The officer in charge of a group of
lights or of a torpedo station is called a director. Though receiving
orders direct from the fortress commander, he has also to co-operate
with the nearest artillery commander. The infantry are posted on the
flanks of the fixed defences, or on the land front. They are divided
into suitable groups, each under a commanding officer, who communicates
with the fortress commander. In large fortresses the area is divided
into sections, each including some portion of the artillery, engineers,
and infantry defence. In such cases the section commanders receive
orders from the fortress commander and pass them on to their
subordinates.
The _intelligence_ system includes communication with the naval signal
stations in the vicinity, one of which is specially selected for each
port as the warning station and is directly connected to some part of
the defences. Another part of the intelligence system deals with the
arrangements for examining all ships entering a harbour. This is usually
effected by posting in each entrance examination vessels, which are in
communication by signal with a battery or selected post on shore. Any
points on shore which can see the approaches are connected by a special
alarm circuit, mainly for use in case of torpedo boat attack.
The _administrative_ system of telephones is used for daily routine
messages. These usually take the form of telephone lines radiating from
a central exchange. In many stations the same lines may be used for
command and administration, or intelligence and command, but at the
larger stations each class of line is kept distinct. (W. B. B.)
COASTGUARD, a naval force maintained in Great Britain and Ireland to
suppress smuggling, aid shipwrecked vessels and serve as a reserve to
the navy. The coastguard was originally designed to prevent smuggling.
Before 1816 this duty was entrusted to the revenue cutters, and to a
body of "riding officers," mounted men who were frequently supported by
detachments of dragoons. The crews of the cutters and the riding
officers were under the authority of the custom house in London, and
were appointed by the treasury. On the conclusion of the war with
Napoleon in 1815 it was resolved to take stricter precautions against
smuggling. A "coast blockade" was established in Kent and Sussex. The
"Ramillies" (74) was stationed in the Downs and the "Hyperion" (42) at
Newhaven. A number of half-pay naval lieutenants were appointed to these
vessels, but were stationed with detachments of men and boats at the
Martello towers erected along the coast as a defence against French
invasion. They were known as the "preventive water guard" or the
"preventive service." The crews of the boats were partly drawn from the
revenue cutters, and partly hired from among men of all trades. The
"coast blockade" was extended to all parts of the coast. The revenue
cutters and the riding officers continued to be employed, and the whole
force was under the direction of the custom house. The whole was divided
into districts under the command of naval officers. In 1822 the elements
of which the preventive water guard was composed were consolidated, and
in 1829 it was ordered that only sailors or fishermen should be engaged
as boatmen. In 1830 the whole service consisted of 50 revenue cutters,
fine vessels of 150 and 200 tons, of the "preventive boats," and the
riding officers. In 1831, during the administration of Sir James Graham,
the service was transferred to the admiralty, though the custom house
flag was used till 1857. After 1840 the men were drilled "in the common
formations," mainly with a view to being employed for the maintenance of
order and in support of the police, in case of Chartist or other
agitations. But in 1845 the first steps were taken to utilize the
coastguard as a reserve to the navy. The boatmen were required to sign
an engagement to serve in the navy if called upon. In May 1857 the
service was transferred entirely to the admiralty, and the coastguard
became a part of the navy, using the navy flag. The districts were
placed under captains of the navy, known as district captains, in
command of ships stationed at points round the coast. Since that year
the coastguard has been recruited from the navy, and has been required
to do regular periods of drill at sea, on terms laid down by the
admiralty from time to time. It has, in fact, been a form of naval
reserve.
The rise and early history of the coastguard are told in _Smuggling
Days and Smuggling Ways_, by the Hon. Henry N. Shore, R.N., (London,
1892). Its later history must be traced in the _Queen's_ (and
_King's_) _Regulations and Admiralty Instructions_ of successive
years. (D. H.)
COASTING, usually called tobogganing (q.v.) in Europe, the sport of
sliding down snow or ice-covered hills or artificial inclines upon
hand-sleds, or sledges, provided with runners shod with iron or steel.
It is uncertain whether the first American sleds were copied from the
Indian toboggans, but no sled without runners was known in the United
States before 1870, except to the woodsmen of the Canadian border.
American laws have greatly restricted, and in most places prohibited,
the practice, once common, of coasting on the highways; and the sport is
mainly confined to open hills and artificial inclines or chutes. Two
forms of hand-sled are usual in America, the original "clipper" type,
built low with long, pointed sides, originally shod with iron but since
1850 with round steel runners; and the light, short "girls' sled," with
high skeleton sides, usually flat shod. There is also the
"double-runner," or "bob-sled," formed of two clipper sleds joined by a
board and steered by ropes, a wheel or a cross-bar, and seating from
four to ten persons.
In Scandinavia several kinds of sled are common, but that of the
fishermen, by means of which they transport their catch over the frozen
fjords, is the one used in coasting, a sport especially popular in the
neighbourhood of Christiania, where there are courses nearly 3 m. in
length. This sled is from 4 to 6 ft. long, with skeleton sides about 7
in. high, and generally holds three persons. It is steered by two long
sticks trailing behind. On the ice the fisherman propels his sled by
means of two short picks. The general Norwegian name for sledge is
_skijalker_, the primitive form being a kind of toboggan provided with
broad wooden runners resembling the ski (q.v.). In northern Sweden and
Finland the commonest form of single sled is the _Sparkstottinger_,
built high at the back, the coaster standing up and steering by means of
two handles projecting from the sides.
Coasting in its highest development may be seen in Switzerland, at the
fashionable winter resorts of the Engadine, where it is called
tobogganing. The first regular races there were organized by John
Addington Symonds, who instituted an annual contest for a challenge cup,
open to all comers, over the steep post-road from Davos to Klosters, the
finest natural coast in Switzerland, the sled used being the primitive
native _Schlittli_ or _Handschlitten_, a miniature copy of the ancient
horse-sledge. Soon afterwards followed the construction of great
artificial runs, the most famous being the "Cresta" at St Moritz, begun
in 1884, which is about 1350 yds. in length, its dangerous curves banked
up like those of a bicycle track. On this the annual "Grand National"
championship is contested, the winner's time being the shortest
aggregate of three heats. In 1885 and the following year the native
_Schlittli_ remained in use, the rider sitting upright facing the goal,
and steering either with the heels or with short picks. In 1887 the
first American clipper sled was introduced by L. P. Child, who easily
won the championship for that year on it. The sled now used by the
contestants is a development of the American type, built of steel and
skeleton in form. With it a speed of over 70 m. an hour has been
attained. The coaster lies flat upon it and steers with his feet, shod
with spiked shoes, to render braking easier, and helped with his gloved
hands. The "double-runner" has also been introduced into Switzerland
under the name of "bob-sleigh."
See _Ice Sports_, in the Isthmian Library, London (1901); _Tobogganing
at St Moritz_, by T. A. Cook (London, 1896).
COATBRIDGE, a municipal and police burgh, having the privileges of a
royal burgh, of Lanarkshire, Scotland. Pop. (1891) 15,212; (1901)
36,991. It is situated on the Monkland Canal, 8 m. E. of Glasgow, with
stations on the Caledonian and North British railways. Until about 1825
it was only a village, but since then its vast stores of coal and iron
have been developed, and it is now the centre of the iron trade of
Scotland. Its prosperity was largely due to the ironmaster James Baird
(q.v.), who erected as many as sixteen blast-furnaces in the immediate
neighbourhood between 1830 and 1842. The industries of Coatbridge
produce malleable iron, boilers, tubes, wire, tinplates and railway
wagons, tiles, fire-bricks and fire-clay goods. There are two public
parks in the town, and its public buildings include a theatre, a
technical school and mining college, hospitals, and the academy and
Baird Institute at Gartsherrie. Janet Hamilton, the poetess (1795-1873),
spent most of her life at Langloan--now a part of Coatbridge--and a
fountain has been erected to her memory near the cottage in which she
lived. For parliamentary purposes the town, which became a municipal
burgh in 1885, is included in the north-west division of Lanarkshire.
About 4 m. west by south lies the mining town of Baillieston (pop.
3784), with a station on the Caledonian railway. It has numerous
collieries, a nursery and market garden.
COATESVILLE, a borough of Chester county, Pennsylvania, U.S.A., on the
west branch of Brandywine Creek, 39 m. W. of Philadelphia. Pop. (1890)
3680; (1900) 5721 (273 foreign-born); (1910) 11,084. It is served by the
Pennsylvania and the Philadelphia & Reading railways, and interurban
electric lines. For its size the borough ranks high as a manufacturing
centre, iron and steel works, boiler works, brass works, and paper, silk
and woollen mills being among its leading establishments. Its
water-works are owned and operated by the municipality. Named in honour
of Jesse Coates, one of its early settlers, it was settled about 1800,
and was incorporated in 1867.
COATI, or COATI-MUNDI, the native name of the members of the genus
_Nasua_, of the mammalian family _Procyonidae_. They are easily
recognized by their long body and tail, and elongated, upturned snout;
from which last feature the Germans call them _Russelbaren_ or "snouted
bears." In the white-nosed coati, a native of Mexico and Central
America, the general hue is brown, but the snout and upper lip are
white, and the tail is often banded. In the red coati, ranging from
Surinam to Paraguay, the tail is marked with from seven to nine broad
fulvous or rufous rings, alternating with black ones, and tipped with
black. Coatis are gregarious and arboreal in habit, and feed on birds,
eggs, lizards and insects. They are common pets of the Spaniards in
South America. (See CARNIVORA.)
COB, a word of unknown origin with a variety of meanings, which the _New
English Dictionary_ considers may be traced to the notions of something
stout, big, round, head or top. In "cobble," e.g. in the sense of a
round stone used in paving, the same word may be traced. The principal
uses of "cob" are for a stocky strongly built horse, from 13 to 14 hands
high, a small round loaf, a round lump of coal, in which sense "cobble"
is also used, the fruiting spike of the maize plant, and a large nut of
the hazel type, more commonly known as the cob-nut.
"Cobbler," a patcher or mender of boots and shoes, is probably from a
different root. It has nothing to do with an O. Fr. _coubler_, Mod.
_coupler_, to fasten together. In "cobweb," the web of the spider, the
"cob" represents the older _cop, coppe_, spider, cf. Dutch _spinnekop_.
COBALT (symbol Co, atomic weight 59), one of the metallic chemical
elements. The term "cobalt" is met with in the writings of Paracelsus,
Agricola and Basil Valentine, being used to denote substances which,
although resembling metallic ores, gave no metal on smelting. At a later
date it was the name given to the mineral used for the production of a
blue colour in glass. In 1735 G. Brandt prepared an impure cobalt metal,
which was magnetic and very infusible. Cobalt is usually found
associated with nickel, and frequently with arsenic, the chief ores
being speiss-cobalt, (Co, Ni, Fe)As2, cobaltite (q.v.), wad, cobalt
bloom, linnaeite, Co3S4, and skutterudite, CoAs3. Its presence has also
been detected in the sun and in meteoric iron. For the technical
preparation of cobalt, and its separation from nickel, see NICKEL. The
metal is chiefly used, as the oxide, for colouring glass and porcelain.
Metallic cobalt may be obtained by reduction of the oxide or chloride in
a current of hydrogen at a red heat, or by heating the oxalate, under a
layer of powdered glass. As prepared by the reduction of the oxide it is
a grey powder. In the massive state it has a colour resembling polished
iron, and is malleable and very tough. It has a specific gravity of 8.8,
and it melts at 1530 deg. C. (H. Copaux). Its mean specific heat between
9 deg. and 97 deg. C. is 0.10674 (H. Kopp). It is permanent in dry air,
but in the finely divided state it rapidly combines with oxygen, the
compact metal requiring a strong heating to bring about this
combination. It decomposes steam at a red heat, and slowly dissolves in
dilute hydrochloric and sulphuric acids, but more readily in nitric
acid. Cobalt burns in nitric oxide at 150 deg. C. giving the monoxide.
It may be obtained in the pure state, according to C. Winkler (_Zeit.
fur anorg. Chem._, 1895, 8, p. 1), by electrolysing the pure sulphate in
the presence of ammonium sulphate and ammonia, using platinum
electrodes, any occluded oxygen in the deposited metal being removed by
heating in a current of hydrogen.
Three characteristic oxides of cobalt are known, the monoxide, CoO,
the sesquioxide, Co2O3, and tricobalt tetroxide, Co3O4; besides these
there are probably oxides of composition CoO2, Co8O9, Co6O7 and Co4O5.
Cobalt monoxide, CoO, is prepared by heating the hydroxide or
carbonate in a current of air, or by heating the oxide Co3O4 in a
current of carbon dioxide. It is a brown coloured powder which is
stable in air, but gives a higher oxide when heated. On heating in
hydrogen, ammonia or carbon monoxide, or with carbon or sodium, it is
reduced to the metallic state. It is readily soluble in warm dilute
mineral acids forming cobaltous salts. Cobaltous hydroxide, Co(OH)2,
is formed when a cobaltous salt is precipitated by caustic potash in
the absence of air. A blue basic salt is precipitated first, which, on
boiling, rapidly changes to the rose-coloured hydroxide. It dissolves
in acids forming cobaltous salts, and on exposure to air it rapidly
absorbs oxygen, turning brown in colour. A. de Schulten (_Comptes
Rendus_, 1889, 109, p. 266) has obtained it in a crystalline form; the
crystals have a specific gravity of 3.597, and are easily soluble in
warm ammonium chloride solution. Cobalt sesquioxide, Co2O3, remains as
a dark-brown powder when cobalt nitrate is gently heated. Heated at
190-300 deg. in a current of hydrogen it gives the oxide Co3O4, while at
higher temperatures the monoxide is formed, and ultimately cobalt is
obtained. Cobaltic hydroxide, Co(OH)3, is formed when a cobalt salt is
precipitated by an alkaline hypochlorite, or on passing chlorine
through water containing suspended cobaltous hydroxide or carbonate.
It is a brown-black powder soluble in hydrochloric acid, chlorine
being simultaneously liberated. This hydroxide is soluble in well
cooled acids, forming solutions which contain cobaltic salts, one of
the most stable of which is the acetate. Cobalt dioxide, CoO2, has not
yet been isolated in the pure state; it is probably formed when iodine
and caustic soda are added to a solution of a cobaltous salt. By
suspending cobaltous hydroxide in water and adding hydrogen peroxide,
a strongly acid liquid is obtained (after filtering) which probably
contains _cobaltous acid_, H2CoO3. The barium and magnesium salts of
this acid are formed when baryta and magnesia are fused with cobalt
sesquioxide. Tricobalt tetroxide, Co3O4, is produced when the other
oxides, or the nitrate, are heated in air. By heating a mixture of
cobalt oxalate and sal-ammoniac in air, it is obtained in the form of
minute hard octahedra, which are not magnetic, and are only soluble in
concentrated sulphuric acid.
The cobaltous salts are formed when the metal, cobaltous oxide,
hydroxide or carbonate, are dissolved in acids, or, in the case of the
insoluble salts, by precipitation. The insoluble salts are rose-red or
violet in colour. The soluble salts are, when in the hydrated
condition, also red, but in the anhydrous condition are blue. They are
precipitated from their alkaline solutions as cobalt sulphide by
sulphuretted hydrogen, but this precipitation is prevented by the
presence of citric and tartaric acids; similarly the presence of
ammonium salts hinders their precipitation by caustic alkalis.
Alkaline carbonates give precipitates of basic carbonates, the
formation of which is also retarded by the presence of ammonium salts.
For the action of ammonia on the cobaltous salts in the presence of
air see _Cobaltammines_ (below). On the addition of potassium cyanide
they give a brown precipitate of cobalt cyanide, Co(CN)2, which
dissolves in excess of potassium cyanide to a green solution.
Cobalt chloride, CoCl2, in the anhydrous state, is formed by burning
the metal in chlorine or by heating the sulphide in a current of the
same gas. It is blue in colour and sublimes readily. It dissolves
easily in water, forming the hydrated chloride, CoCl2.6H2O, which may
also be prepared by dissolving the hydroxide or carbonate in
hydrochloric acid. The hydrated salt forms rose-red prisms, readily
soluble in water to a red solution, and in alcohol to a blue solution.
Other hydrated forms of the chloride, of composition CoCl2.2H2O and
CoCl2 . 4H2O have been described (P. Sabatier, _Bull. Soc. Chim._ 51,
p. 88; Bersch, _Jahresb. d. Chemie_, 1867, p. 291). Double chlorides
of composition CoCl2.NH4Cl.6H2O; CoCl2.SnCl4.6H2O and
CoCl2.2CdCl2.12H2O are also known. By the addition of excess of
ammonia to a cobalt chloride solution in absence of air, a
greenish-blue precipitate is obtained which, on heating, dissolves in
the solution, giving a rose-red liquid. This solution, on standing,
deposits octahedra of the composition CoCl2.6NH3. These crystals when
heated to 120 deg. C. lose ammonia and are converted into the compound
CoCl2.2NH3 (E. Fremy). The bromide, CoBr2, resembles the chloride, and
may be prepared by similar methods. The hydrated salt readily loses
water on heating, forming at 100 deg. C. the hydrate CoBr2.2H2O, and at
130 deg. C. passing into the anhydrous form. The iodide, CoI2, is produced
by heating cobalt and iodine together, and forms a greyish-green mass
which dissolves readily in water forming a red solution. On
evaporating this solution the hydrated salt CoI2.6H2O is obtained in
hexagonal prisms. It behaves in an analogous manner to CoBr2.6H2O on
heating.
Cobalt fluoride, CoF2.2H2O, is formed when cobalt carbonate is
evaporated with an excess of aqueous hydrofluoric acid, separating in
rose-red crystalline crusts. Electrolysis of a solution in
hydrofluoric acid gives cobaltic fluoride, CoF3.
Sulphides of cobalt of composition Co4S3, CoS, Co3S4, Co2S3 and CoS2
are known. The most common of these sulphides is cobaltous sulphide,
CoS, which occurs naturally as syepoorite, and can be artificially
prepared by heating cobaltous oxide with sulphur, or by fusing
anhydrous cobalt sulphate with barium sulphide and common salt. By
either of these methods, it is obtained in the form of bronze-coloured
crystals. It may be prepared in the amorphous form by heating cobalt
with sulphur dioxide, in a sealed tube, at 200 deg. C. In the hydrated
condition it is formed by the action of alkaline sulphides on
cobaltous salts, or by precipitating cobalt acetate with sulphuretted
hydrogen (in the absence of free acetic acid). It is a black amorphous
powder soluble in concentrated sulphuric and hydrochloric acids, and
when in the moist state readily oxidizes on exposure.
Cobaltous sulphate, CoSO4.7H2O, is found naturally as the mineral
bieberite, and is formed when cobalt, cobaltous oxide or carbonate are
dissolved in dilute sulphuric acid. It forms dark red crystals
isomorphous with ferrous sulphate, and readily soluble in water. By
dissolving it in concentrated sulphuric acid and warming the solution,
the anhydrous salt is obtained. Hydrated sulphates of composition
CoSO4.6H2O, CoSO4.4H2O and CoSO4.H2O are also known. The heptahydrated
salt combines with the alkaline sulphates to form double sulphates of
composition CoSO4.M2SO4.6H2O (M = K, NH4, &c.).
The cobaltic salts corresponding to the oxide Co2O3 are generally
unstable compounds which exist only in solution. H. Marshall (_Proc.
Roy. Soc. Edin._ 59, p. 760) has prepared cobaltic sulphate
Co2(SO4)3.18H2O, in the form of small needles, by the electrolysis of
cobalt sulphate. In a similar way potassium and ammonium cobalt alums
have been obtained. A cobaltisulphurous acid, probably H6[(SO3)6.Co2]
has been obtained by E. Berglund (_Berichte_, 1874, 7, p. 469), in
aqueous solution, by dissolving ammonium cobalto-cobaltisulphite
(NH4)2Co2[(SO3)6.Co2].14H2O in dilute hydrochloric or nitric acids, or
by decomposition of its silver salt with hydrochloric acid. The
ammonium cobalto-cobaltisulphite is prepared by saturating an
air-oxidized ammoniacal solution of cobaltous chloride with sulphur
dioxide. The double salts containing the metal in the cobaltic form
are more stable than the corresponding single salts, and of these
potassium cobaltinitrite, Co2(NO2)6.6KNO2.3H2O, is best known. It may
be prepared by the addition of potassium nitrite to an acetic acid
solution of cobalt chloride. The yellow precipitate obtained is washed
with a solution of potassium acetate and finally with dilute alcohol.
The reaction proceeds according to the following equation: 2CoCl2 +
10KNO2 + 4HNO2 = Co2(NO2)6.6KNO2 + 4KCl + 2NO + 2H2O (A. Stromeyer,
_Annalen_, 1855, 96, p. 220). This salt may be used for the separation
of cobalt and nickel, since the latter metal does not form a similar
double nitrite, but it is necessary that the alkaline earth metals
should be absent, for in their presence nickel forms complex nitrites
containing the alkaline earth metal and the alkali metal. A sodium
cobaltinitrite is also known.
Cobalt nitrate, Co(NO3)2.6H2O, is obtained in dark-red monoclinic
tables by the slow evaporation of a solution of the metal, its
hydroxide or carbonate, in nitric acid. It deliquesces in the air and
melts readily on heating. By the addition of excess of ammonia to its
aqueous solution, in the complete absence of air, a blue precipitate
of a basic nitrate of the composition 6CoO.N2O5.5H2O is obtained.
By boiling a solution of cobalt carbonate in phosphoric acid, the acid
phosphate CoHPO4.3H2O is obtained, which when heated with water to
250 deg. C. is converted into the neutral phosphate Co3(PO4)2.2H2O (H.
Debray, _Ann. de chimie_, 1861, [3] 61, p. 438). Cobalt ammonium
phosphate, CoNH4PO4.12H2O, is formed when a soluble cobalt salt is
digested for some time with excess of a warm solution of ammonium
phosphate. It separates in the form of small rose-red crystals, which
decompose on boiling with water.
Cobaltous cyanide, Co(CN)2.3H2O, is obtained when the carbonate is
dissolved in hydrocyanic acid or when the acetate is precipitated by
potassium cyanide. It is insoluble in dilute acids, but is readily
soluble in excess of potassium cyanide. The double cyanides of cobalt
are analogous to those of iron. Hydrocobaltocyanic acid is not known,
but its potassium salt, K4Co(CN)6, is formed when freshly precipitated
cobalt cyanide is dissolved in an ice-cold solution of potassium
cyanide. The liquid is precipitated by alcohol, and the washed and
dried precipitate is then dissolved in water and allowed to stand,
when the salt separates in dark-coloured crystals. In alkaline
solution it readily takes up oxygen and is converted into potassium
cobalticyanide, K3Co(CN)6, which may also be obtained by evaporating a
solution of cobalt cyanide, in excess of potassium cyanide, in the
presence of air, 8KCN + 2Co(CN)2 + H2O + O = 2K3Co(CN)6 + 2KHO. It
forms monoclinic crystals which are very soluble in water. From its
aqueous solution, concentrated hydrochloric acid precipitates
hydrocobalticyanic acid, H3Co(CN)6, as a colourless solid which is
very deliquescent, and is not attacked by concentrated hydrochloric
and nitric acids. For a description of the various salts of this acid,
see P. Wesselsky, _Berichte_, 1869, 2, p. 588.
_Cobaltammines._ A large number of cobalt compounds are known, of
which the empirical composition represents them as salts of cobalt to
which one or more molecules of ammonia have been added. These salts
have been divided into the following series:--
Diammine Series, [Co(NH3)2]X4M. In these salts X = NO2 and M = one
atomic proportion of a monovalent metal, or the equivalent quantity
of a divalent metal.
Triammine Series, [Co(NH3)3]X3. Here X = Cl, NO3, NO2, 1/2SO4, &c.