OPERATIONS OF 1839.
~Shipping Station and Pier at Hynish.~
During the winter months which intervened between November 1838 and
March 1839, a small detachment of men, consisting of three masons, nine
quarriers, and one smith, were left at Hynish under the superintendence
of Mr Charles Barclay, to clear the landing-place of several patches
of rock which encumbered the entrance. They were also to build some
walls of inclosure, and to quarry and dress stones for the pier
and other buildings at Hynish. The provision of accommodation for
shipping at that place was now naturally regarded as of more urgent
necessity than formerly, because the importation of stones from Mull,
which the failure of the Tyree stone had rendered unavoidable, led to
the necessity of a reshipment of all the materials at Hynish, where
they were dressed before being sent to the Rock. It may, perhaps, be
naturally enough imagined, that instead of importing the materials to
be dressed at Tyree and there reshipped in order to be carried to the
Rock, they might have been prepared in Mull, and sent directly to the
Skerryvore; but many things concurred to render this inexpedient, if
not altogether impracticable. The advantage of being able, by means of
a good telescope, in some measure to ascertain the state of the sea
at the Rock, the comparative shortness of the passage, which gave the
prospect of several cargoes being landed on it in one day during fine
weather, and the convenience of communicating with the Rock by signal,
were circumstances in themselves quite sufficient to determine my
choice in favour of Hynish, as the place from which the materials must
be shipped for the Rock, even if there had been no other considerations
leading to the same conclusion. But in addition to all this, I could
not fail to perceive that Hynish was the only place for the permanent
station of the vessel attending on the future Lighthouse; and that on
that account alone the construction of a Harbour there was unavoidable.
That the arrangement, by which the future station for the Tender was
used as the workyard for the operations, was the most judicious that
could have been adopted, was fully proved by my subsequent experience
of the advantage of assembling all our materials and all our force at
a point as near to the Rock as possible, so that we might be at all
times ready to supply defects or omissions, and take advantage of every
favourable change of the sea or sky.
In the middle of March the _Regent_ conveyed from Aberdeen a detachment
of twenty-nine masons and quarriers and five smiths, and the foreman
of the workyard, who, together with the men already at Hynish and the
native labourers, were to be employed during the season of 1839, in
the various departments of the work. On their arrival the men were
separated into two small bands, of which the one, consisting of six
masons, twelve quarriers, one smith and a foreman, was stationed at
North Bay in Mull, where the new quarries were to be opened; while the
other had its head quarters at Hynish, and, when not engaged in the
work on the Rock itself, was subdivided into smaller parties, varying
in number with the nature of the particular operations in which the men
were occupied.
~Granite quarries in Mull.~
On the afternoon of the _19th April_ I sailed from Greenock in the
_Regent_, for North Bay in Mull, where the quarries were to be opened.
We had on board the whole materials of the new Barrack, which was to
supply the place of that which had been destroyed in the preceding
month of November; and we had also a party of carpenters who came to
fit up the Barrack in a temporary manner at North Bay, as a residence
for the masons who were to be engaged in preparing more permanent
dwellings for the quarriers and in forming a landing-wharf for the
shipment of the stones for Tyree. It was not till the 25th, after a
tedious passage of six days, that we anchored at North Bay; and next
morning we had the satisfaction of seeing the steamer, the _Skerryvore_
(by which name she was specially set apart for the service of the
works), arrive in the Bay with a party of masons and quarriers, who had
been appointed to meet us in order to begin the work.
The necessary arrangements with the Duke of Argyll’s tenants at the
_Ross_ of Mull (in which district North Bay is situated) having been
already made, no time was lost in erecting the wooden Barrack; and, in
seven days after our arrival, the masons and quarriers entered their
new habitation under the charge of Mr Charles Stewart, whom I left as
foreman of the North Bay works. Mr Stewart and his party, following the
example of diligence thus set to them, were not less expeditious in
proceeding with the work which had been assigned to them; and by the
beginning of August a range of barracks, capable of accommodating forty
persons, had been erected, a landing wharf had been built, and various
storehouses had been provided, although the quarry had to be opened,
and the blocks of stone required for those various works were still _in
situ_ at the time of our landing at North Bay three months before.
The landing wharf is placed on a small projecting face of rock in a
depth of 12 feet at high water of ordinary spring tides. It presents
a face of 40 feet in length, and was provided with wooden fenders
for the protection of the vessels loading stones. Landward of it a
considerable space was levelled, by cutting and filling, to serve
as a yard for storing the quarried materials, so as to be ready for
shipment. The quarry itself was opened in the face of a hill, so steep
as almost to deserve the name of a cliff; but advantage was taken of a
deep gully which intersected it and in it an inclined plane was formed
communicating directly with the landing-place. This gully was partly
cleared by excavation of the rock and partly, where necessary, its
inequalities were smoothed down by filling it with stone shivers; and
along its bed thus prepared, longitudinal sleepers of timber were laid,
to which _edge-rails_ were attached.
At the top of the incline two iron drums or barrels were set, and round
them were wound, in opposite directions, the chains by which the trucks
or wagons, loaded with stones from the quarry, were lowered to the
wharf below. A powerful break apparatus was attached to those barrels,
to check the velocity of the descending wagons, which was also in part
counteracted, by making their gravity act as a power to raise the empty
wagons in the same manner as is usually practised in coal-mines.
The quarry itself, as already stated, was opened in the face of the
cliff, at a point where the successive beds of solid rock seemed to
promise the fairest prospect of success. The preliminary operation was
to remove a very thin alluvial cover which scarcely concealed from
view a large mass of most beautiful granite, whose reddish colour
is said to have given the name of _Ross_[19] to that part of Mull,
the shores of which everywhere exhibit massive slopes of that fine
rock. The granite is separated very abruptly from the basalts of the
surrounding district, so as to leave the Ross purely granitic; but in
no part of the whole coast, which abounds with creeks and bays, does
the rock appear to be of equal quality, or so conveniently situated
for shipping, and so easily accessible to quarriers, as at the spot
we had chosen. I know of no instance of a quarry so fully answering
the most sanguine expectations as that of the Ross of Mull; and I
have never seen a granite quarry of equally great resources, as
regards both the quantity and the quality of the material produced.
The rock in general yielded easily before well-directed shots, and
was separated into large masses, capable of being advantageously
cut, with little loss of material, into shapely blocks, by means of
wedges, which work remarkably well in that rock. A few weeks after the
quarrying operations had been commenced, a single shot detached 150
tons of excellent stone, in the cutting of which into blocks for the
Lighthouse Tower little loss of material occurred; and in the course
of the season of 1839, although the summer was chiefly spent in the
preliminary works above noticed, the Mull quarries produced nearly as
much workable material for the Lighthouse Tower as the Hynish quarries
had done in three years. In the course of the future working of the
quarry, when it came to be more fully opened, its resources were so
great, that on one occasion a single shot shook about 570 tons, while
another shot detached a mass of 460 tons. In that way, between April
1839 and June 1840, material had been quarried in that single spot,
sufficient to supply 4300 selected blocks, varying in weight from ³⁄₄
ton to 2¹⁄₂ tons each. The average monthly produce of the quarries was
about 400 tons, and there were generally employed in them 26 quarriers,
3 labourers, and 2 smiths. The quantity of gunpowder consumed in the
quarry was small, as it was almost exclusively employed in great bores
about 11 feet deep, for the purpose of detaching large masses which
had no _open side_ and could not be removed by means of the _pinch_ or
_crow-bar_. When a mass of rock had been thus removed, it was cut up
into various portions by means of wedges, and finally subdivided into
blocks, _hammer_ (or as it is called _quarry_) _dressed_, according
to rough moulds, whose dimensions exceeded those of the stones of the
various courses of the building by a quantity which was considered
sufficient to cover any casualty in the final dressing of the block
by the masons at Hynish, and which allowance was generally equal to a
film of rock about 1¹⁄₂ inch in depth. The blocks thus roughly formed
were shipped for Hynish, distant about 26 miles, through a tempestuous
sea, open to the full reach of the Atlantic towards the south-west,
sometimes in a small vessel called the “Queen,” belonging to the
Commissioners, and sometimes in undecked boats of 16 tons, belonging
to the adventurous men of Tyree. The freight usually paid was 5s. a
ton, and yet the whole of the blocks for the Lighthouse Tower, and many
of those used in the pier at Hynish, were laid down to the number of
about 5000, at the rate of 2s. 1¹⁄₂d. per cubic foot, including all the
expense of building barracks, opening quarries, freight of stones, and
the expense of building and maintaining the small vessel called the
“Queen,” above noticed. The stone of the Mull quarries is a reddish
or flesh-coloured granite, in which felspar predominates. About 13·66
cubic feet weigh a ton, and it is not quite so hard as the granite of
Aberdeen.
[19] Whether from any inflection of the Celtic _Rhua_, or _Roy_, or
directly from the Italian _Rosso_, it would, perhaps, be impossible
to determine.
~Observations on the quarrying of granite.~
As I am not aware that any professional work contains a detailed
description of the quarrying of granite, some observations on that
subject may not be unacceptable in this place; and I therefore propose,
at the risk of appearing somewhat prolix, to give a pretty minute
account of the mode of opening and working a granite quarry, more
especially as practised by us at North Bay.
Having laid bare the rock of earth, gravel, or other loose matter
(which operation, as I have elsewhere mentioned, is in Scotland
technically called _terring_), and having swept or washed clean the
surface of the rock so as to have a good view of the natural seams or
joints which traverse it, the next step is to fix the best place for
putting in a bore or mine.
In selecting the position of the bore, the direction of the seams and
veins of the rock must be duly considered, with a view to employ the
force of the explosion to the greatest advantage in separating the
natural joints or beds of the rock, instead of shattering the solid
_masses_ or _posts_ (as they are called in the language of the quarry)
into shivers or fragments.
One thing to be strictly borne in mind is, that the bore should never
be in the centre of a fine or large block, but should be placed within
a few inches of its back so as not to break the finer rock into small
and useless fragments; and care must, at the same time, be taken to
keep the bore clear of cracked or unsound rock, as the jumper, in
passing through such material, is liable to be jammed by the cracks
and fissures before it can be driven to the proposed depth. It is not
possible to lay down precise rules for guiding the quarrier in choosing
the place of the bore, as his plan must be regulated chiefly by the
circumstances of each case; but it may be observed, that having first
determined the depth of the hole, it will seldom be found advantageous
to keep the bore farther back from the face of the rock than about
_four-fifths_ of that depth. The depth itself, also, to which the mine
should be carried, is a point for deliberation with the skilful and
experienced quarrier, who will take great care not to go so deep as to
pass through the solid rock in which he is boring and thus to touch
a bed, unless indeed he shall think it advisable to attempt to raise
more than one _post_ of rock by a single mine, in which case he will
carry the bore through the first post into the second or third as the
case may be. But in all cases the boring must be stopt at two inches
before coming to the bed or seam of the post in which the mine is to
terminate, lest the exploding powder should escape by the bottom of the
bore, and thus leave the top of the rock altogether undisturbed. In
endeavouring to procure large materials, the bores should in general be
as deep as possible. It is only experience, however, which teaches the
quarrier to form a sound _prognosis_ as to the direction and level of
the beds of the rock at any particular spot, and enables him to choose
the most advantageous position and depth for the mines.
In the blasting of granite there are a few general rules which
(although it may not be necessary to follow them in every case) may
be considered as constituting the best practice. If the bore be a
vertical one of the depth of 6 feet, 2¹⁄₂ inches diameter at the
top, diminishing to 2 inches at the bottom, may be considered a
proportionate caliber. If the bore be a deep one (perhaps of 14 feet),
its diameter will require to be 3¹⁄₂ inches at the top, and should
diminish to 2³⁄₄ inches at the bottom; and the quantity of powder
required for the charge will in most cases be about as much as is
required to fill ²⁄₅ths of the hole.[20]
[20] Miners and quarriers, who always work by empirical rules,
disregard entirely the _line of least resistance_ as a measure for
the _charge_, and invariably refer to the _depth_ of the bore.
The patent _fusee_ having been inserted among the powder, with its end
about the centre of the charge, and the upper part of the bore having
been filled up with dried clay, well forced down with a wooden rammer
faced with copper, a length of 3 or 4 inches of the _fusee_ should be
left outside the bore, to which the match is to be attached. Having
cleared away every thing near the blast which can receive any injury
and covered up the machinery of the cranes with strong planks, the
mine may be said to be ready for being fired; and, on a signal given,
by blowing a horn, all hands retreat to a safe distance, with the
exception of the fireman, who then lights the match, and follows the
others as fast as possible.
If, as already stated, the object in quarrying be to obtain large
materials, the bores should, if possible, be deep; and, in that case,
the rock will seldom be thrown down in fragments by the blast, but will
merely be cracked, and intersected by rents about one inch in width.
Recourse must therefore be had to what, in quarry language, is called
a _Bull_, which consists in running a quantity of loose powder into
the crack which has been made by the blast, at that part where its
explosion seems most likely to throw out the cracked or broken mass
in various fragments and disengage them from their place in the rock.
In _bulling_, perhaps twice as much powder as was used in the bore is
loosely poured into the crack, care being at the same time taken to get
as much of it to go under the bottom of the rock as possible. After
enough of powder has been poured into the crack, a quantity of dried
smithy ashes, or dry sand, is run in over the powder, so as completely
to cover it, except so much as is required to fire it by; and that
coating, which is merely superficial, is employed partly to keep down
the powder, and partly for security against its being accidentally
fired before all things are ready. The fireman having seen every thing
cleared away, gives notice to sound the alarm, when all hands escape
to a distance in the direction which is supposed to be the safest. The
match is then applied, and the fireman retires, as fast and as far as
he can, yet so as if possible to keep in view, during his retreat, the
progress of the match. The operation of _bulling_ is far more dangerous
than the firing of a bore, as the charge is much greater, and not so
well confined, so that many splinters are thrown off, and the direction
in which they fly varies continually with the direction of the cracks
which the original bore may have produced. As might be expected, by far
the greater part of the accidents which occur to firemen in granite
quarries, arise from that practice.
[Illustration: No. 12]
Should it happen, as it sometimes does, that after having gone through
those operations, the quarrier fails in getting the cracked mass
thrown down to the bottom of the quarry, he varies his mode of attack,
and proceeds to bore a row of _plug-holes_ on the face of the rock
in such a line as to cut off a part from one end of the shaken mass;
and for that purpose he is often obliged to hang a scaffold over the
face of the rock on which to stand while boring the holes. Those
plug-holes should be slightly inclined, so that, when the wedges,
called _plugs_[21] and _feathers_, are driven into them, they may rend
the rock in such a direction that the piece intended to be cut off may
be a little narrower on the inner than the outer face, so that, thus
resting on an incline it may be more easily taken out. The plug-holes
should be cut at one foot asunder, and bored with a jumper 1¹⁄₂ inch
diameter to the depth of 9 inches; and if the plug-holes be deep, and
some difficulty in driving be expected, the plugs should be carefully
greased or oiled previously to being driven. Having cut off a block
as above described, an attempt may be made, if the mass be great, to
throw it down by means of _bulling_; but if it be of lesser dimensions,
and there be reason to expect that it may be removed in the ordinary
way, the power of the crane may be applied to draw it down. For that
purpose, the quarrier employs an instrument called a _Dog_, which is
a strong short hook, armed like a pick on the point with steel, and
having a ring in the end of it for the hook of the crane-chain to pass
through. Having cut a small hole with a pick, on the upper part of the
block which is meant to be removed, the _steeled_ point of the dog is
inserted into it, in such a manner that the weight of the crane-chain
may retain it steadily in its place. Five or six men then heave on
the crane a strain just as much as they suppose it may bear, without
danger of carrying away any of its fixtures; and as many men as can
find room are, at the same time, employed at the top of the rock,
working with crow-bars behind the block, so as to shake it and loosen
its hold. The two parties continue their work reciprocally, leading
and following,--the men at the crane, still keeping up the strain, and
taking care not to heave so much as to break any of the chains, while
those on the top continue to shake the block by means of the crow-bars,
or throw in stones into the opening, which is always getting wider
between the block and the cliff, so as to prevent the loosened mass
from falling back into its old place. When the block has been drawn as
far forward as to appear just ready to fall over the cliff, one of the
most expert men at the crane stands carefully watching the movement of
the block; and whenever the stone begins to fall, he instantly throws
the crane _out of the gear_, so as to prevent the wheelwork being
pulled to pieces by the tumbling mass getting entangled in the chains,
on which it frequently falls and breaks them to pieces. The operation
of taking down large blocks from a great height is very tedious, and
is often attended with much danger, as the stone, when it falls on the
bottom of the quarries, makes the shivers among which it alights fly in
all directions with a force which nothing can withstand.
[21] The _plug_ (fig. 12, _c_ _c′_), and _feathers_ (fig. 12,
_d_ _d′_), are flat pieces of malleable iron, slightly tapered, and
forming together a kind of compound wedge, the two feathers being
first inserted into the hole, and the plug being driven between them
by a series of gentle blows, from malls of the weight of from 30 lb.
to 35 lb.
An opening being made in the manner above described, by getting one
piece brought down, the same process is continued by cutting off and
taking down pieces of eight or ten tons weight, until there be as many
blocks in the floor of the quarry as can be easily managed at one time.
Those masses are then arranged by means of the crane in convenient
positions for being cut up into blocks of the requisite sizes; and as
all of them are within range of the crane, they can with its assistance
be easily turned over or set in any position. While some of the men
are employed in cutting up those blocks, others are clearing away the
rubbish, and others are boring holes or making ready for a fresh blast.
[Illustration: No. 13.]
If those blocks, which we have supposed to be brought down to the
quarry floor and to be ready for cutting, exceed seven feet in depth
of cut, their farther subdivision will require the use of the plugs
and feathers already described; but if their depth or thickness fall
short of that, the ordinary iron wedges will answer. If the cut be of
the depth of about 6 feet, the wedges must be placed about 3 inches
apart from side to side; but if the depth of cut be less, they may be
set 4 or 5 inches asunder. The method of setting in those wedges is
as follows:--The person who cuts the wedge-holes generally works in
a sitting posture, and if the block will admit of it, he prefers to
bestride it, with a stone, as a stool, under each foot. He works with a
pick of 16 lb. weight, having a handle only 16 inches long, with which
he cuts the first hole generally about 3 inches from the end of the
block. The holes are for the most part about 2¹⁄₂ inches deep, and 3¹⁄₂
inches long, and must be well cleared out at the bottom with a sharp
pick; and the wedges must be set in a line as fair and straight as
possible. Cutting wedges of that kind are of iron, from 7 to 9 inches
long, and 2¹⁄₂ inches broad, and weigh about 7 lb. weight each. When
in good order they must not be sharp in the mouth, but about ³⁄₈ of an
inch thick, to prevent their _grounding_ in the bottom of the hole; for
if they but touch the bottom of the hole, they fly out at the first
touch of the mall. When the wedges have been all properly arranged for
a cut, the workman proceeds to give each of them in succession a gentle
tap, so as to make them all fast; and for that purpose he uses a mall
about 30 lb. weight (fig. No. 13), and having a handle 2 feet 9 inches
long. He then goes over all the wedges, giving each of them a smart
blow in regular, yet not too rapid succession, but allowing a little
time for the parts of the stone to separate gradually. If the wedges be
forced too quickly, there is great danger of the cut being spoiled by
its flying out obliquely at one side, and thus not reaching throughout
the whole depth of the block. The blocks, when thus subdivided by
means of the wedges, are generally nearly of the size required by the
rough moulds sent from the workyard, and are fit to be carried to the
stone-cutter’s shed.
[Illustration: Fig. 14.]
As a conclusion to the above account of quarrying, it may perhaps be
thought desirable to give some notion of the probable time required to
perform certain parts of that sort of work. In boring holes of 1 inch
to 1¹⁄₄ inch in diameter, it may be observed that they are generally
done with the _hand mall_ (fig. No. 14), one and the same person
striking with the mall with one hand, and turning the boring tool for
himself with the other; and in most cases a man will bore 9 or 10
inches an hour in granite rock. If the bore be 1¹⁄₂ inch diameter, as
for plugs, three men will generally bore two plug holes in one hour,
each hole being about 9 inches deep. If the bore be for blasting and of
2 or 2¹⁄₂ inches diameter, three men will bore, at the rate of one foot
per hour, to the depth of 6 or 7 feet; but if the bore be for a large
blast of 13 or 14 feet deep, the hole must be 3¹⁄₂ inches in diameter
at the top (diminishing to 2³⁄₄ inches at bottom), and will employ
three men working hard between two and three days. Bores of that sort,
indeed, cannot be made (at least by hand) to a greater depth than 14
or 15 feet, as the weight of a rod of iron, 17 feet in length, and 2
inches in diameter, makes it quite unmanageable for one man either to
turn or to lift; while, from its great mass, the strokes of the mall
produce little effect on it. The malls used in boring holes, which
require three men, are 7 or 8 lb. weight, having handles 3 feet long
(fig. No. 15), and are swung over the shoulder, while striking for
_down bores_, in the same manner as a smith’s forehammer is used. An
expert cutter with the wedges will make good wages by cutting holes at
the rate of 2¹⁄₂d. for a dozen of holes, taking light and heavy cuts as
they come to hand.
[Illustration: No. 15.]
What has been said above of boring and blasting refers only to
_downright_ or vertical bores; but, in the lower parts of a quarry, it
is often necessary to have recourse to what are called _breast-bores_,
from their running in a nearly horizontal direction and piercing the
front or breast of the rock. Those bores are not so easily made as
the _downright_ bores and, in general, are only used where the rock
is low, or in taking up bottom rock. They can seldom be carried to
a greater depth than about 9 or 10 feet, owing to the difficulty of
turning the jumper, and can never be bored quite horizontally, but
require as much dip as will retain a little water in the hole to keep
the jumper moving. Instead of throwing the mass outward, as is done
by _down-bores_, those _breast-bores_ generally only cut or break the
stone in the direction or line of the bore, so that the block always
requires to be afterwards removed by _bulling_, in the manner already
described.
~Dressing of the Lighthouse blocks.~
The dressing of the blocks for the Lighthouse Tower, as already
mentioned, was one of the most important operations in the workyard
at Hynish; and as no writer with whom I am acquainted has given any
account of the mode now practised of dressing granite, I hope I shall
be excused for attempting, in this place, to give some idea of the
method employed by the masons of Aberdeenshire, whose skill in that
department of workmanship is well known both in our own and in other
countries. As the whole of the materials for the Tower were to be
dressed in such a manner as to avoid the necessity of any fitting
on the Rock, by the introduction of what are technically called
_closers_, the greatest accuracy in the formation of the moulds
from which the stones were to be shaped became necessary. With that
view, I had a _trainer_ or _radius_ made with a moveable _vernier_,
capable of sliding along it, so as to give the differences between
the _readings_ of the feet, as far as to the _thirtieth_ part of an
inch; and I was thus enabled to lay off the _batter_ or slope on each
course (according to the quantities in the Table of Co-ordinates in
the Appendix) with great nicety, and so to trace very distinctly the
contour of the intended column.[22] On the stone floor of an apartment
in one of the workshops, the _quadrant_ of each course of the building
was carefully drawn out, at full size, and divided into the sectors
which were required for preserving a due _bond_ among the joints of
the adjoining courses. The form of each stone in the tower having been
thus determined by those full-sized draughts, moulds, representing the
_beds_ and _sides_ of each stone, were prepared according to them,
of seasoned timber, well shielded at the angles with sheet-iron, to
prevent their being injured. Those moulds having been marked with
reference to the number of the course, and the position of the stones
in the wall, were given to the foreman of the workyard, who regulated
the work of each of the stone-cutters, often to the number of 70 men.
A proper block having been selected for each stone, leaving about 1¹⁄₂
inch all round the extremity of the moulds when applied to its several
faces, it was conveyed, by means of the sling-cart, to the shed where
it was to be dressed. The shed for dressing granite stones differs in
no respect from an ordinary mason’s shed, except in its greater height;
but, as the stone cutter, in order to wield his tools to advantage,
must, at certain parts of the work, stand on the top of the block, it
has been found, that a height of about 15 feet is required for the
back-wall of a granite mason’s shed. Each man also requires, for large
blocks, a space of about 10 feet (measured along the front of the
shed), as his peculiar territory.
[22] Such nicety, I would observe, was by no means superfluous,
because the arrangements of the Tower precluded the possibility of
using a trainer in building; and as the whole was done by means of
_plumb-templets_, the greatest accuracy in tracing the curve of the
Tower became necessary, as the only true basis of good workmanship on
the Rock.
When a block has been brought to the shed, the first thing to be
done, if it is a large stone of 1¹⁄₂ or 2 tons weight, is to lay it
nearly level on the ground, with the side which is to be first dressed
uppermost. The form or _plan_ is then sketched upon it according to the
mould, and the stone is _blocked_ out with a large hammer weighing 30
or 35 lb. (fig. No. 16), which is the most suitable weight for ordinary
men, although a stout man will manage one of 40 lb. well enough, if
the block be lying in an advantageous position. When the stone has
been thus rudely _blocked_ out, it is set upon its edge with a gentle
inclination to one side, so that the mason, who mounts on the top of
it, may conveniently use a pick of 18 lb. weight, having a handle three
feet long, to dress off very roughly the most prominent parts of its
irregular surface. In doing that he makes a great many deep ruts in
a downward direction, at the same time taking care that none of them
shall be so deep as to fall below the general surface of the stone when
finished. When he has in that style dressed as far down the surface of
the stone as he can conveniently reach, (and that is generally about
half way,) the stone is then thrown over and set up on the opposite
edge, when he again mounts upon it, and goes over the rest of the
surface in the same manner, until the whole shall be reduced to one
rough plane, so that in spite of numerous partial inequalities, the
general face may be straight, or what is technically termed _out of
winding_. A stone in that state is also said to be _well opened_.
[Illustration: No. 16.]
[Illustration: No. 17.]
[Illustration: No. 18.]
The next step is to raise the stone so that it may incline at about 30°
or 40° with the horizon; after which the mason, standing at the higher
side, commences to put on the _draughts_ or _guide-lines_ all round the
edge of the face which he has just _opened_. For that purpose he first
employs a pick of about 12 lb. weight, having a handle about 2 feet in
length (fig. No. 17), with which he dresses a band of about 3 inches
broad, taking care that this band or draught be straight and _out of
winding_. He then, with the pick, goes over the whole face between
the draughts, dressing off all the ridges which still remain between
the ruts which he had made while the stone was standing on edge, as
before noticed, so that the whole surface will present the appearance
of a pretty regularly _dabbed_ face. Having arrived at that stage, he
next proceeds to put on the _true draughts_ (as round the edges of the
stone, as in the case of the _guide-lines_), with the cast-steel chisel
or _punch_ (_a_, _a′_, fig. No. 18), and a small iron-mall of 3¹⁄₂ lb.
weight; and afterwards with the axe, he carefully _axes_ a band about
2¹⁄₂ inches broad, so as to be quite out of winding, and as straight as
possible all round. The dressing is then completed between those bands.
If the block be a broad one, the mason will probably be able to take
in only one half of the face at a time; and, in that case, the stone
must be let down at the high side, and the other one raised as high as
may be necessary to enable him to work to advantage. If the surface
thus dressed, which is in this case supposed to be the largest side, be
intended for the _bed_ of a stone, the knobs or high points between the
_pick-dabs_ are merely roughly dressed down with a blunt axe, so as to
be all as low as the axed lines or draughts round the extremities, and
thus to present no convexity on which the stone, when laid, could rock;
but if the surface should be meant for a fine _face_, the dressing
must be commenced with a bluntish axe, taking care that all the axe
marks be made quite across the stone, at right angles to the side
where the workman stands. The whole face having been once gone over in
that manner with a blunt axe, a sharper and well ground axe is next
used for crossing the first axing in such a manner that all the second
axe-marks may be inclined at an angle of 45°, or thereby, with the
first. The whole face having been thus brought to a smoother and more
uniform surface, the third and last axing follows; and then the mason
uses his shortest and lightest axe, which must, for that work, be well
ground and sharp. That axing must be done right across the block, or in
the same direction as the first axing had been done, and in that state
the surface of the stone may be supposed to be fine enough for most
kinds of work used in housebuilding or in public works; but for very
fine work, such as some sepulchral monuments, or for surfaces which are
afterwards to be polished, it is not unusual to axe four or even five
times, care being always taken that how often soever that operation may
be performed, the axing should never be made twice consecutively in
the same direction, for by that precaution alone can a true and even
surface be obtained. (The form of the axe is shewn in fig. No. 19.)
[Illustration: No. 19.]
[Illustration: No. 20.]
The dressing of the first face being finished in the manner described,
the block is laid flat on the ground, and the plan or form of the stone
is then accurately drawn on it, according to the mould, with some
substance that makes a bright or good mark, such as a piece of tile
ground sharp, or a thin splinter of logwood. If there be much _waste_
to be taken off beyond the lines so drawn, a hammer, whose weight must
be in proportion to the piece to be struck off, is applied; but care
must be taken not to come too near the lines with the hammer, and it
is generally safe to leave at least an inch outside of them. The piece
which is left gives a good hold for the _chipper_ or _pincher_ (fig.
No. 20), which is next carefully applied along the line, being steadily
held within one hand, and with the other sharply struck with a small
iron mall of 3¹⁄₂ lb. weight, having a short handle about 8 inches in
length. While the _chipper_ receives sharp strokes in succession with
the mall, it must be slowly moved several times along the line from
one end of the stone to the other, till the piece projecting beyond
the line, or a part of it, breaks off. Such is the power of this small
instrument, that it not infrequently cuts down to a depth of 9 or
even 12 inches, thereby doing more execution and to greater purpose,
than a heavy hammer can generally accomplish, even in the hands of a
skilful workman. The _chipper_ is a tool lately introduced; but has
now become a most important article in every hewer’s _kit_. It makes a
regular and clean cut, and leaves little to be done by the punches and
chisels (fig. No. 18, in p. 122), in preparing the _arris_ of the next
face of the stone. The block is now raised a little from the ground,
and the workman standing at its higher side, the axing of which he
has just finished, puts on with the punches and chisel a fine band or
draught along the side next to that just dressed. He then applies to
the finished face the _square_ or _bevel_, according to the inclination
of the faces, and dresses a band across the stone at each end of the
block; and, finally, joins those two cross bands by means of another
band along the back. In that way the external draughts on the second
side are completed. He then with the pick and axe dresses away the
material between those draughts until the second face is finished;
and the same process is repeated for each side of the block which
requires to be dressed. If the block be a large one, and it require
to be dressed on all its sides, it will, lastly, be cut to the proper
thickness or height, which is regulated by means of a gauge, known,
in the technical language of the shed, as “_a grippers_” (fig. No.
21),[23] from its embracing the stone on three sides. It is simply
a three-sided iron templet, having one long and one short tail (at
right angles to the connecting piece), the space between the two tails
shewing the thickness of the stone.
[23] The figure shews “_a grippers_” for a stone 14 inches thick.
[Illustration: No. 21.]
The practical reader will readily see, that what has been said above
about the hewing of granite, is chiefly applicable to the dressing
of the large stones used in public works, such as docks, bridges, or
marine towers; and it may be proper to add, that such heavy materials
are always dressed on the ground, and that a piece of wood is placed
under each end of the stone as a necessary precaution to prevent its
being split by the blows of the mall. In dressing the lighter materials
for house building, where a good deal of fine work is generally
required, the stones are laid on what is called a _banker_, similar to
that which is used in hewing freestone. The banker is a bench of stone
2¹⁄₂ or 3 feet long, and 2 feet broad, and is raised about 2 feet above
the ground, so as to suit the workman’s convenience.
In dressing one of the outside stones of the first or lowest courses
of the Skerryvore Tower, a mason was occupied _eighty-five_ hours (see
Plans of courses, Plate VIII.); and in dressing one of the largest of
the hearting or inner stones of the same courses, _fifty-five_ hours.
But as the work proceeded, owing to the greater readiness which the
men had acquired in the application of the moulds, gauges and bevels,
the time occupied, gradually decreased to the extent of about _ten
hours_ for each stone, until the work had been carried on as far as
to the thirteenth course, where the number of outside stones was
reduced to twenty-four, at which stage of the work, the time required
for dressing increased to about _one hundred and twenty hours_ for
each outside stone. From that point upwards, the time again gradually
decreased till we reached the sixty-fourth course, where it may be
stated, that, on an average, a man was employed _sixty-three_ hours in
dressing each stone; but the time gained in the last instance seemed
to depend less on the readier application of the implements, than on
the gradual diminution in the size of the stones, which, from that
level upwards, decreased along with the thickness of the wall. But
above the sixty-fourth course, a very marked increase in the time
of dressing took place, owing to the introduction of the _ribband
or ring joggles_ (shewn in the Plans of the 84th and 94th courses,
Plate VIII.); and to the substitution of the _dovetailed joggles_ in
the place of the _square_ or _diamond joggles_, which were used in
the lower parts of the building. The time required for dressing a
stone of the sixty-fifth course was _ninety-three_ hours of one man,
a circumstance which strikingly shews, that a small, and, apparently,
trifling alteration in the style of workmanship may sometimes increase
to a considerable extent, the expense of a great work. Each radiating
stone of the _eighty-fourth_ course, which forms the floor that goes
quite through the wall, required _one hundred and sixty-one hours_ for
its completion; and the other radiating floor-stones, which did not
pass quite through the wall to the outside, occupied one man about _one
hundred and twenty hours_. Each centre stone of the floors into which
the others were dovetailed, required about _three hundred and twenty
hours_ of one man’s time. The time of a labourer occupied in cutting a
hole for the dovetailed Lewis bats, by which the stones were raised,
was about _three hours_.
The tools necessary fully to equip a granite mason are as follows:--One
dressing hammer about 16 or 18 lb. weight; 6 dressing picks, from 12 to
20 lb. weight; one small hand-mall, or mash-hammer, about 4 lb. weight;
3 stone axes about 7 lb.; 16 or 18 cast-steel punches and chisels,
with one or two chippers or pinchers of 2¹⁄₂ lb. weight. One large
blocking-hammer of 30 or 32 lb., may very well serve for eight men. The
value of a granite mason’s _kit_ may be estimated, when in good working
order, at about L.7. A very great revolution has taken place during a
few years in the method of working granite. The most important change
is the substitution of the hand-mall and chisel in the operation of
putting the _drafts_ or bands on the stones, in place of _arris-picks_,
which made the workmanship clumsy, tedious and imperfect, by slowly
grinding down the stone at a great expense of labour to the hewer,
who was forced to remain bent forward in an irksome posture, without
the relief which is obtained by occasionally shifting his position, a
change, which, every one who has been long employed in any laborious
occupation, knows well how to value. The introduction of the _chipper_
may also be regarded as one of the most important modern improvements
in the art of working granite; and had it not been for those changes,
the actual expense of dressing the blocks for the Skerryvore Tower, as
ascertained from the journals of the works, would have been exceeded
by a sum of between L.4000 and L.5000; and it may even be questioned
whether it would have been at all practicable with such tools to cut
the dovetailed spaces of the floors out of the solid stone.
~Excavation of Foundation for the Lighthouse Tower on the Skerryvore
Rock.~
The excavation of the foundation of the Lighthouse Tower was the
first operation which engaged my attention at Skerryvore Rock, at
the beginning of the season of 1839. It was commenced on the 6th of
May, and was continued up to the last hour of our remaining on the
Rock, on the 3d of September. A more unpromising prospect of success
in any work than that which presented itself at the commencement of
our labours, I can scarcely conceive. The great irregularity of the
surface, and the extraordinary hardness and unworkable nature of the
material, together with the want of room on the Rock, greatly added to
the other difficulties and delays, which could not fail, even under
the most favourable circumstances, to attend the excavation of a
foundation-pit on a rock at the distance of 12 miles from the land. The
Rock, as already noticed, is a hard and tough gneiss, and required the
expenditure of about _four times_ as much labour and steel for boring
as are generally consumed in boring the Aberdeenshire granite.
After a careful survey of the Rock, and having fully weighed all the
risks of injuring the foundation, I determined at once to enter upon a
horizontal cut, so as to lay bare a level floor of extent sufficient
to contain the foundation pit for the Tower. The very rugged and
uneven form of the Rock made this an almost necessary precaution, in
order to prevent any misconception as to its real state, for it was
traversed by numerous veins and bands inclined at various angles, on
the position and extent of which the stability of the foundation in no
small degree depended. That operation occupied 30 men for 102 days, and
required the firing of no fewer than 246 shots, chiefly horizontal,
while the quantity of material removed did not greatly exceed 2000
tons. It was a work of some hazard; for the small surface of the
Rock confined us within 30, and sometimes within a dozen yards of the
mines, while its form afforded us no cover from the flying splinters.
The only precautions we could adopt were to cover the mines with
mats and with coarse nets, which I had caused to be made during the
previous winter, of the old ropes of one of the Lighthouse Tenders,
and in each blast to apportion very carefully the charge of powder to
the work that was to be done. That was managed with great skill by
Charles Barclay, the foreman of the quarriers, who charged all the
bores, and, along with myself, fired all the shots. So completely did
the simple expedient of covering the bores with nets and mats check the
flight of the stones, that, except on one or two occasions, none of
the splinters reached us, and all the damage done was a slight injury
to one of the cranes. Perhaps, also, our safety may, in some measure,
be attributed to a change which I introduced into the mode of charging
the horizontal shots, by which all the risk of pushing home the powder
in the ordinary mode with the _tamping rod_ is avoided. That change
consisted in using a kind of shovel, formed of a rod, armed with a
hollow half-cylinder of sheet copper, which contained the powder, and
being inverted by giving the rod half a turn round its axis, made the
powder drop out when the cylinder reached the bottom of the bore. It
was, in all respects, excepting size, the same as the charging-rod used
for great guns. The amount of materials removed by blasting, as nearly
as I could ascertain, was only about 1000 cubic yards; and, taking
all the circumstances into account, it may be doubted whether there
be any instance in modern engineering of an operation _of so small
an extent_ occupying so much time, and involving so great risk. The
blasting of the Rock, however, was not the only difficulty with which
we had to contend, for it also became necessary to remove the quarried
materials, amounting to about 2000 tons, into the deep water round
us, to prevent their being thrown by the waves upon the Rock, and so
endangering the future temporary Barrack. That was rather a laborious
work, and occupied two cranes, with temporary runs and trucks, during
the greater part of the time we spent on the Rock. I am well aware that
the quantity of materials which I have just mentioned, will be apt
to produce a smile from those who have been chiefly conversant with
the gigantic but simple operations which generally characterize the
great railways of this country; but if it be remembered that we were
at the mercy of the winds and waves of the wide Atlantic, and were
every day in the expectation of a sudden call to leave the Rock, and
betake ourselves to the vessel, and on several occasions had our cranes
and other tools swept into the sea, the slowness of our progress will
excite less surprise; and still less will those who duly weigh the
dangers of our daily life, both in our little vessel and on the Rock,
and who, at the same time, reflect on the many striking proofs which
we almost every hour experienced of the care of an Almighty hand, be
disposed to withhold their sympathy from the heartfelt expressions of
gratitude which often went round our little circle in the boats, as we
rowed in the twilight from the Rock to the ship. Isolation from the
world, in a situation of common danger, produces amongst most men a
freer interchange of the feelings of dependence on the Almighty, than
is common in the more chilly intercourse of ordinary life.
With a view to lessen the dangers of blasting in such a situation,
I had provided a galvanic battery on the plan proposed by Mr Martyn
Roberts, but I used it less frequently than I intended. The attachments
of the wires were very liable to be broken from various causes, where
there were many men congregated in a small space; and as we could not
venture to leave the apparatus on the Rock, the frequent re-shipment of
it in a heavy sea was another cause of the derangement of its parts. I
soon, therefore, laid it aside, and only had recourse to it when any
work was to be done under water, or in cases where the simultaneous
firing of several mines (for which it is admirably adapted) was of
importance in effecting any special purpose.
When the floor had been roughly levelled I again carefully surveyed the
Rock, with the view of fixing precisely the site of the foundation-pit,
and of taking advantage of its form and structure to adopt the largest
diameter for the Tower of which the Rock would admit. In some places
I found that parts of the Rock, apparently solid, had been undermined
by the constant action of the waves, to the distance of 13 feet inward
from its face; but none of those cavernous excavations reached the main
nucleus, so that, after much deliberation and repeated examinations of
all the veins and fissures, I was enabled to mark out a foundation-pit
42 feet in diameter, on one level throughout. That was a point of no
small importance; and although it had cost great labour at the very
outset, much time was saved by it in the subsequent stages of the
work. Not only was the labour thereby avoided of cutting the rock into
separate terraces, and fitting the blocks to each successive step,
as was done by Smeaton at the Eddystone; but the certainty that we
had a level foundation to start from, enabled us at once to commence
the dressing of stones without regard to any irregularities in the
surface of the Rock; and the building operations, when once commenced,
continued unimpeded by the necessity for accommodating the courses to
their places in the foundation-pit, so that the Tower soon rose above
the level, at which there was the greatest risk of the stones being
removed by the waves before the pressure of the superincumbent building
had become great enough to retain them in their places.
The outline of the circular foundation pit, 42 feet in diameter, having
been traced with a trainer on the rock, numerous jumper-holes were
bored in various places, having their bottoms all terminating in one
level plane, so as to serve as guides for the depth to which the basin
was to be excavated. The depth did not exceed 15 inches below the
average level, already laid bare by the cutting of the rough horizontal
floor which has just been described; and before the close of the season
of 1839, about _one-third_ of the area of the circle had been cleared,
and was ready for the final pick-dressing which prepared it for the
reception of the first course. The excavation of this circular basin
was conducted with the greatest caution, and few shots were permitted
to be fired lest the foundation should in any place be shaken by the
action of the gunpowder on any of the natural fissures of the Rock. The
work was chiefly done by means of what are called _plugs and feathers_,
the form of which has already been shewn in the woodcuts (No. 12,
p. 115). In that part of the work the bores were nearly horizontal,
and the action of the _plug and feathers_ was to throw up a thin
superficial shelf or paring of rock of from 6 to 12 inches in depth,
and not more than 2 feet square. By that painful process an area of
about 1400 superficial feet was cleared. The chief trouble connected
with that operation was cutting, by means of the pick, a vertical
face for the entrance of the horizontal _jumpers_ or boring rods; and
wherever advantage could be taken of natural fissures it was gladly
done. Another considerable source of labour was the dressing of the
vertical edges of the basin, as that implied cutting a _square check_,
15 inches deep and about 130 feet long, in the hardest gneiss rock; and
the labour attending which, can only be fully estimated by a practical
stone-cutter who has wrought in such a material. The plan employed was
to bore all around the periphery of the circle, 1⁵⁄₈ inch vertical
jumper-holes, 6 inches apart, to the required depth, and to cut out
the stone between them. The surface thus left was afterwards carefully
dressed, so as to admit vertical and horizontal moulds, representing
truly the form of the masonry which the check was intended to receive.
The experience of the labour attending that operation gave me great
reason for congratulation on having adopted a foundation on one level
throughout, instead of cutting the rock into several terraces, at each
of which the same labour of cutting angular checks must necessarily
have been encountered. The cutting of the foundation occupied 20 men
for 217 days in all, whereof 168 days were in the season of 1839, and
the rest in the summer of 1840.
~Fitting up of the Second Barrack on the Rock.~
~Sudden death of George Middlemiss.~
The minute details given in my account of the destruction of the
first Barrack, have entirely superseded the need for any particular
description of the fitting up of the second Barrack on the Rock; and
I shall therefore confine myself to a brief notice of the work in the
chronological order in which it occurred. On the 1st of July, after the
level floor for the foundation of the Tower had been roughly cleared,
and all risk of injury from the firing of mines was past, the boring
of holes for the fixtures of the second Barrack was begun; and so
great were our exertions, that in the short period of fourteen days,
the pyramidal frame-work on which the Barrack-house was to stand (see
Plate V.), consisting of 13 beams, of about 50 feet in length, with all
their braces, ties and stancheons, and the malleable iron cap which
secured their union at the top, was firmly fixed on the Rock. After
the pyramid was completed, the Barrack-house (which had previously
been removed from North Bay, where, as already noticed, it had served
as a temporary abode for the men who opened the quarries there), was
transported, piece-meal, from Hynish to the Rock as required; for it
was not considered prudent, after the experience of last year, to
trust, even in the finest part of the season, a great quantity of
timber to _lashings_ on the Rock. The fitting-up of the Barrack-house
was completed on the 3d September and occupied only eleven days; so
that the whole work extended to only twenty-five days, a remarkably
short time for such a work, in such a situation. That despatch, indeed,
was only obtained by working (as we did both during the excavation of
the foundation and the erection of the Barrack), at all times when the
weather would permit, from four o’clock in the morning till eight, and
even nine in the evening, with an interval of only half-an-hour for
breakfast and the same for dinner. The erection of the Barrack was a
work of great difficulty and anxiety; for, as every thing depended on
the exact union of all its parts, the slightest error in any dimension
would have stopped the work until it could be remedied, a delay which,
in such a situation, would, at certain stages of its progress, have
proved fatal to the whole structure. I cannot, therefore, omit this
opportunity of paying a tribute, in passing, to the memory of the
late Mr George Middlemiss, the foreman of the carpenters who fitted
up the Barrack, whose zeal for the completion of the work was very
conspicuous. Poor Middlemiss died very suddenly at Hynish, about a
fortnight after the completion of his labours on the Rock. He had
received some instructions from me, so late as 11 o’clock, on the night
of the 20th September; and when one of the men went to call him next
morning at 6 o’clock, he was found dead, and in such a state as led Mr
Moxey, the surgeon attached to the works, after a careful examination,
to conclude, that he had died of paralysis of the heart, about three
hours before he was found, or not more than four hours after I had seen
him, to all appearance, in perfect health!
~Wharf and Landing-place on the Rock.~
No inconsiderable part of the labour of this season was devoted to the
clearing of the landing-place, which was formed in a natural creek
(see Plate III.) and in excavating the rocks in front of the line of
wharf, so as to admit the vessels carrying the building materials to
come alongside of it. That work could only be done at certain times of
tide and during very fine weather, and was, therefore, tedious as well
as hazardous. After two entire days spent in cutting with a sickle,
mounted on a long pole, the thick cover of gigantic sea-weed, which hid
the true form of the Rock from view, we were able to mark out the line
of the wharf; and after all the mines were bored and charged and the
tide had risen, and every one had retired from the spot, the whole were
fired at the same instant, by means of the galvanic battery, to the
great amazement and even terror of some of the native boatmen, who were
obviously much puzzled to trace the mysterious links which connected
the drawing of a string at the distance of about 100 yards, with a low
murmur, like distant thunder, and a sudden commotion of the waters in
the landing-place, which boiled up, and then belched forth a dense
cloud of smoke; nor was their surprise lessened, when they saw that
it had been followed by a large rent in the rock; for so effectually
had the simultaneous firing of the mines done its work, that a flat
face for a quay had been cleared in a moment, and little remained to be
done, to give the appearance of a regular wharf and to fit it for the
approach of a stone lighter, except attaching wooden fenders and a trap
ladder.
~Ring-bolts, Water-Tanks, and Railways.~
A good deal of time was also spent in fixing a great many ring-bolts
on various parts of the Rock and its _outlyers_, for the use of the
shipping, which we expected to carry stones to the Rock the next
season and in clearing a line for a permanent iron railway, about
50 yards long, from the landing wharf to the Tower, the position of
which is shewn in Plate III. The railway was used for the conveyance
of materials from the stone-lighters to the building, and is now the
_highway_ for all the stores which pass from the wharf to the Tower.
Means were also taken for laying down two cast-iron water-tanks on the
Rock in tolerably sheltered positions, as shewn in Plate III. One of
those tanks was completed and filled with water, but the sole-plate
only of the other was fixed, as unfortunately one of the plates dropped
from the vessel’s side into the water, while the seamen were lowering
it into one of the boats, a loss which prevented the second tank from
being finished till the next year. Those tanks, together, held about
900 gallons, and contained our chief supply of water during the whole
subsequent progress of the works, when there were often about fifty men
on the Rock.
~Incidents of the Season.~
I shall conclude this Chapter, by noticing a few incidents which
occurred during the season of 1839, serving, in some degree to throw
light upon the peculiar difficulties we had to encounter, or tending to
shew the importance of the work in which the Commissioners had engaged.
~Effects of a gale from the S.W.~
On the 9th of August a strong gale suddenly sprang up from the S.W.,
which, while it lasted, caused us much alarm and anxiety at Hynish,
whither we had been driven from our station at the Rock to seek shelter
at the commencement of the storm. Several small pieces of timber,
which we had left on the Rock when we were forced to leave it, came
ashore in Balaphuil Bay; and it was generally reported in the Island
that the Barrack had, for the second time, been destroyed. That report
I did not credit, as I had great confidence in the fixtures which
attached it to the Rock; but my anxiety to ascertain the true state of
the case, led me to examine the south-eastern shore of Tyree, when all
that could be discovered was a few pieces of loose timber, and one of
the smith’s cooling tubs, which had been washed from the Rock. Next
day, however, the smith’s bellows came ashore in the same Bay, and so
little injured, that we had them repaired and put in use again on the
Rock. On the 12th of August, when the weather permitted us to return
to our station at the Skerryvore, we found all the timbers which had
been lashed down with chains to the Rock scattered in every direction
around the beams of the Barrack, the smith’s forge overturned, the
bellows of course gone; one of the cranes also which had been used
for the removal of the excavated materials had been swept away, and
not a vestige of it left, except a small piece of one of the wooden
stays, which the force of the waves had broken. But that which most
of all surprised us, and gave us the greatest concern, as an alarming
proof of the force of the sea and a source of great inconvenience and
hazard during the rest of the season, was the disappearance of our
moorings, which had been lost by the _foundering_ of the cask buoy in
the heavy surf which the gale had raised. During all the rest of our
stay at the Rock that season, we were forced to ride at anchor in foul
rocky ground of the worst and most irregular description, over which
the vessel frequently drifted to a considerable distance, occasioning
us no small fear for our safety. That was the second set of moorings
which had disappeared at Skerryvore; and a stronger proof of the very
great power of the western swell can hardly be imagined, as nothing of
the kind had happened during the whole time the Bell Rock works were
in progress. That circumstance also convinced us of the necessity of
adopting vessels of small burden for landing the materials. So great,
indeed, was the difficulty of _hanging_ even the boats at the Rock,
that on two occasions (on the nights of the 4th May and 12th July) we
had both the boats half filled by the sea, and nine or ten men thrown
out on the Rock by the _kanting_ of one of the boats at the recoil
of the wave. The landing department was indeed, throughout the whole
season, attended with great difficulty, and was to me a source of
constant anxiety; for, in the daily transport to and from the vessel
and the Rock of 30 men, unaccustomed to boating, during a period of
four months, it was more than could have been expected that we should
have been preserved from the loss of either life or limb. On the night
of the 3d September, when we left our anchorage at the Skerryvore
for the season, every heart was full of rejoicing, and many cordial
expressions of gratitude to our Almighty Protector were uttered in deep
whispers by the more seriously disposed men, whose number bore a goodly
proportion to our whole band. I cannot omit saying, in this place, that
both Mr Macurich, who acted as landing-master on the Rock, and the
late Mr Heddle, the master of the steam-tender, conducted the boating
department in a most masterly style.
~Mutiny of the Crew.~
As an aggravation of our difficulties, we were occasionally much
annoyed by the unprincipled and cowardly conduct of a few of the
seamen, who, despite the contempt of their comrades, fearing or
pretending to fear the risk of lying all night so near the face of the
Rock, spared no pains to spread alarm, and made several attempts, by
threatening desertion, to extort a rise of wages. They even spoke of
leaving the vessel at the Rock, which they could easily have done by
some of the native boats which called in passing to see the progress
of the works; and Mr Heddle, the master of the steamer, was forced to
dismiss the mutineers on the first occasion when the vessel was driven
for shelter to the land, and to rely during the rest of the season
on the native boatmen to supply their place. That firm conduct had,
for some time afterwards, the desired effect on those who remained;
but the spirit of disaffection having spread pretty widely, we had
subsequently several other instances of sudden desertion from the
service.
~Near approach of Vessels to the Rock, and other circumstances
shewing the importance of a Light on the Skerryvore.~
In the course of my residence for four months on board the tender
moored off the Rock, I had opportunities of witnessing many proofs
of the great necessity which existed for a Light on the Skerryvore;
and if I had ever entertained any doubt as to the beneficial effects
of such an establishment, the experience of the season of 1839 must
have entirely removed it. It often happened that for several days
successively, not fewer than five or six vessels of large size, both
outward and homeward bound, were visible at distances varying from
3 to 6 miles from the Rock; and much anxiety was often felt by us
for the safety of those vessels, several of which approached so near
the outlying rocks as to keep us for some time in the most painful
suspense. On two occasions, more especially, I was about to direct the
steam to be raised, in order that the Skerryvore tender might be sent
to warn the masters of vessels of their danger, or if too late for
that, to afford them assistance in case of accident. On the 29th of May
a large schooner, and on the 13th of June a large brig ran right down
upon the western _outlyers_, called FRESNEL’S Rocks (which were covered
at the time), and just _put about_ in time to avoid striking; and on
the 12th June, a fine foreign barque (apparently a Prussian) passed so
close to Bo-Rhua as to leave us for a short time in doubt whether or
not she had struck on it. On the 21st of June, also, a large brig came
very near the rocks which lie off Tyree, at the base of Ben-Hynish,
in trying to avoid Boinshley Rock, which lies about 5 miles to the
N.W. of the Skerryvore. Those circumstances, together with the list
of shipwrecks already given at page 23, afford strong proofs that the
Skerryvore Rock occupies a most fatal position in a great fairway much
frequented by large vessels bound to or from ports in the Irish Sea and
in the Clyde.
There cannot be a doubt that many vessels have been wrecked on the
Skerryvore and its numerous _outlyers_, being borne down upon the reef
by the strong tide which runs at the rate of between four and five
miles an hour at the height of spring tides; and the natives of Tyree
have many stories about chains and anchors and hidden treasures, with
which their fancy has filled every nook of the Rocks. To what extent
those stories, which are often most circumstantially told, may be true,
it is not easy to determine; but in the end of July 1839, we succeeded,
under the guidance of a native boatman, in raising from a creek in one
of the detached shelves to the south-west of the main Rock, an anchor
worn by the action of the sea to a mere skeleton, a circumstance which
so far corroborates the truth of their traditions.