OPERATIONS OF 1841.
~Hynish workyard.~
The workyard at Hynish presented a very busy scene during the summer
and winter of 1840; and the desolation and misery of the surrounding
hamlets of Tyree seemed to enhance the satisfaction of looking on our
small colony, where about 150 souls were collected in a neat quadrangle
of cleanly houses, conspicuous by their chimnies and windows amongst
the hovels of the poor Hebrideans, who generally make no outlet for
the smoke in their gloomy dwellings, but permit it to escape by the
doors. The regular meals and comfortable lodgings and the cleanly and
energetic habits of the Lowland workmen, whose days were spent in toil
and their evenings, most generally, in the sober recreations of reading
and singing, formed a cheering contrast to the listless, dispirited,
and squalid look of the poor Celts, who have none of the comforts of
civilized life and are equally ignorant of the value of time and the
pleasures of activity.
The number of masons employed in 1841, varied from 60 to 84 and they
were chiefly engaged in dressing blocks for the Lighthouse-Tower, in
discharging the cargoes of vessels loaded with stone from Mull and also
in shipping stones for the Rock, in which operation, their acquaintance
with the handling of dressed materials and their readiness in working
the cranes, made them very useful in directing and also in working
along with the native labourers, who, partly from incapacity and
partly from excessive indolence, could not be trusted for a moment to
themselves. During that year, upwards of 38,000 cubic feet of granite
were dressed into blocks with straight beds and joints, and with faces
of double curvature, so as to suit the contour of the Tower, when
arranged in the wall. The blocks were also fitted with stone joggles,
for retaining them in their places, and with lewis-holes for raising
them in the manner usually practised in building materials of that
description. Of those materials upwards of 70 blocks were floor-stones
(see Plans of 84th and 85th courses, Plate VIII.), _dovetailed_ on
the heads, _checked_ on the joints and having a plain surface on the
upper and a concave one on the under bed. The necessity of preserving
throughout their entire joints a perfect uniformity of bearing, made
the dressing of those materials a work of great nicety; and each
stone, as before noticed, being cut according to moulds, was fitted
temporarily in its place on the platform at Hynish, previously to its
being laid aside as ready for transport to the Rock. Those various
operations were conducted with great care; and the stones, which were
regularly arranged and numbered according to a schedule, formed, at the
time I left the workyard in the end of October, a considerable pile,
bearing ample testimony to the diligence and zeal of Mr James Scott,
the foreman of the workyard and leader of the party ashore.
~The Rock.~
Owing to the uncertain and stormy weather in spring, it was not till
the 13th of May, that the first landing was effected on the Rock. The
result of our visit, however, was most satisfactory. We found the
Barrack quite as we had last seen it six months before; and not one
joint of the pile of masonry, which we had left exposed to the waves,
had been shaken or _started_. The Railway and Landing Wharf, although
much exposed to the breach of the sea, had survived the winter’s storms
with no greater damage than the loss of one of the sleepers or beams,
on which the rails rested, which had been torn by the waves from its
fixtures to the rock. It was not till a week after our first landing
that we were enabled again to take up our quarters on the Rock; for
we had few landings in the mean time, and some of them, owing to the
heavy surf which played round the Rock, were of no very satisfactory
kind. Our first experience of this season was indeed far from inviting.
So difficult was the first landing, that we were forced to direct
all our endeavours to laying in a small stock of provisions in the
Barrack, before being left on the Rock; and, considering the scanty
nature of the supplies which the weather permitted us to secure, it
was thought prudent to restrict the number of men to eight masons and
myself, with as many tools as we could land, to enable them to make the
necessary repairs and arrangements before fairly commencing for the
season the works of a more strictly progressive character. The vessel
then returned to Tyree with the rest of the men and all the heavy
apparatus which we could not land; and, to add to the unpleasantness
of being left in such a position, with the improbability of a visit
from the vessel for several days, one of the masons took alarmingly
ill soon after the steamer was too far off for a signal, and suffered
so acutely during the whole night, that his piercing cries in the
spasms which accompanied his disorder, combined with the howling of a
strong _north-wester_ and the incessant lash of the waves, deprived
the whole party of sleep during the first night. In this uncomfortable
predicament, until the steamer returned on the 22d, we spent two days
exposed to winds piercingly cold and in apartments soaked with spray,
which found its way through inlets which had been made by the winter’s
storms. We were not sorry, at the same time, to have an opportunity
of removing the poor man to the care of Dr Campbell, the surgeon who
was attached to the workyard at Hynish and of reinforcing our stock of
provisions and the detachment of men. We also succeeded in landing the
cranes and other building apparatus, which, owing to the heavy surf on
the 20th, we had not been able to accomplish.
The few first days after getting fairly established in our habitation
for the season, were occupied in extending the railway to a point on
the northern part of the Rock, somewhat sheltered during certain seas
(see Plate III.), where a crane for stowing the materials previously
to building them had been erected; and thus it was not till the 25th of
May that the first cargo of stones was landed. Next day a crane (then
thirty-four years old), which had been used in the building of the Bell
Rock Lighthouse, was placed on the top of the masonry, and the more
cheering operations of mixing the mortar and of _setting_ stones were
begun.
In spite of the unfavourable state of the weather and the continual
distraction of our exertions, occasioned by storms and the landing of
materials, we continued our operations with such vigour as to complete
the solid part of the masonry of the Tower on the 8th July. Until the
building had reached to the level of 15 feet, the work was carried on
by the use of two jib-cranes, one on the Rock and the other on the
Tower, by means of which latter the stones were _set_, after being
_brought to hand_ by the first. But above that level, _shear-legs_
similar to those used at the Eddystone, were employed. Those shear-legs
were about 50 feet high, and were erected in the situation, at the side
of the Tower, shewn in Plate III. They consisted of two spars attached
at the base to _jointed_ sockets _batted_ into the Rock, and connected
at the top by means of a crosshead of timber. The jointed sockets
permitted the shears to hang forward at any angle suited to the level
and distance of the part of the Tower to be reached; and chain guys
both in front and behind, secured them from falling either backwards or
forwards. At the crosshead hung an iron sheave with a chain, one end
of which was provided with a hook for raising stones, while the other
was wound around the barrel of a _crab machine_ well batted down to the
rock, by working which the blocks were raised to such a level as to
be within reach of the building crane on the top of the masonry. The
_shear-poles_ were used, until the building of the Tower was completed,
to raise the stones the first lift of forty feet above the Rock. In
the later stages of the work, the stones, instead of being taken by
the building cranes directly from the _shear-poles_, were raised from
storey to storey by means of crabs placed inside the Tower, which
worked chains, _reeved_ through sheaves hanging from the end of beams
projecting from the windows. Such beams are called _needles_, and are
described at page 504, and shewn in Plate IX., fig. 3, of my Father’s
Account of the Bell Rock Lighthouse, where they were used for the same
purpose.
~The Waves.~
~Colours of breaking Waves.~
During the early part of the season the weather was intensely cold,
with showers of sleet and heavier showers of spray, which dashed round
us in all directions, to the great discomfort of the poor masons, whose
apartments did not admit of a large wardrobe, while they had not the
benefit of much room for drying their clothes at the small _coboose_
or cooking-stove in the Barrack. For days together, also, the men
were left without building materials, owing to the impossibility of
landing them, or, what was worse, without the power of building what we
had on hand in consequence of the violence of the winds. During such
times we often felt much anxiety about the safety of the stones which
we had piled on the rock ready for being built; and it took no small
trouble, by the occasional application of the crane, to save them from
being swept into the sea by the surf. Nothing struck me more than the
illusive effect produced on the mind by the great waves which rolled
past the rock. The rapidity of their movements, and the noise which
accompanied their passage through the gullies and rents of the rugged
reef, seemed to give them the appearance of being much larger than they
really were; and, even when viewed from the Tower, after it had risen
to the height of 30 feet, they seemed, on approaching the rock, to be
on the eve of washing right over the top of the building and sweeping
all before them into the sea. It was a long time before, by continually
watching the waves and comparing their apparent height with the results
of their impact on the rock, we were enabled to correct our notions of
their magnitude, so as to mark the approach of their crested curling
heads with composure; and some of the party never became sufficiently
familiarized with those visitors, to avoid suddenly looking round when
the rush of a breaker was heard behind them, or recoiling a few paces
when they saw its towering crest apparently about to burst in a torrent
over their heads. It was only after a long residence on the rock and
continual experimental observation, that I acquired confidence to
approach within a few feet of the point which I expected the breakers
to reach. I occasionally suffered for my temerity, by being thoroughly
drenched with spray; but by long perseverance, I attained considerable
skill in predicting the limits of their influence, though ever and anon
an extraordinary wave overthrew all our confidence, by bursting far
above the boundaries which we had assigned in our minds. That, however,
did not generally occur in calm weather, but after strong gales from
the N.W., when the waves had assumed the larger and more flattened form
known by the name of the _ground-swell_. To gauge the height of those
waves by means of a vertical rod, graduated with large divisions, so
as to be read at a little distance, as the waves washed it in passing,
was an object I had long in view; but I found it utterly impossible
to apply any fixture in the deep water, in a situation fitted for the
purpose. By making numerous comparisons, however, of the waves, with
various known points of rock near the main Rock, and by availing myself
of the observations of some of the more intelligent of the masons, I
was led to conclude, that the greatest elevation of an unbroken wave,
measuring from the hollow to the crest, does not, in the sea around the
Skerryvore, exceed 15 feet; but the sailors, perhaps from their being
less accustomed to accurate measurement, generally estimated it at 30
or even 40 feet. I was often much interested, while I sat watching the
waves that boiled round us on every side, to observe the peculiar tints
which they assumed at the moment of breaking, passing as they did from
the bluish-green colour of solid water by very rapid changes, to a
delicate and very evanescent _blush_ of rose colour, which invariably
accompanied their greatest state of comminution or disintegration.
Those appearances I have often observed in other places, and I
supposed them to be produced by _reflection from the thin plates of
water_; and took them for indications of the perfect homogeneousness of
the sea-water, in regard to density, and also of the similarity of its
condition at the _moment_ of breaking.
~The Seals.~
Amongst the many wonders of the “great deep,” which we witnessed at the
Skerryvore, not the least is the agility and power displayed by the
unshapely seal. I have often seen half a dozen of those animals round
the Rock, playing on the surface or riding on the crests of curling
waves, come so close as to permit us to see their eyes and head, and
lead us to expect that they would be thrown _high and dry_ at the
foot of the Tower; when suddenly they performed a somersault within a
few feet of the Rock, and diving into the flaky and wreathing foam,
disappeared and as suddenly reappeared a hundred yards off, uttering
a strange low cry, as we supposed, of satisfaction at having caught
a fish. At such times the surf often drove among the crevices of the
Rock a bleeding cod, from whose back a seal had taken a single moderate
bite, leaving the rest to some less fastidious fisher.
The latter part of the season, although not so stormy as the first,
was far from being favourable for the building operations which, on
one occasion, even during the month of July, were suspended for five
days by a violent gale, which made it unsafe to attempt standing on the
Tower. Happily the wind was from the N.E., a quarter from which it has
comparatively little power in raising heavy seas, otherwise we should
infallibly have lost a large part of the dressed materials which lay
piled on the Rock, and, in all probability, should have had our work
thus prematurely cut short in the middle of summer.
After building a few courses above the level of the solid part of the
Tower, the jib-crane could no longer be conveniently used, and recourse
was had to a _balance-crane_, which, during the previous winter, I
had caused to be constructed at Edinburgh, in the workshop of Mr
James Dove. That apparatus, which, except as to its greater size and
strength, in order to suit the greater dimensions of the Tower, was
almost identical with that which was used at the Bell Rock, is shewn
in Plate IX.; and it is only necessary, in this place, to notice its
general construction and mode of working, which is also shewn in Plate
XVII. of my Father’s Account of the Bell Rock Lighthouse. In the hollow
of the Tower, a cast-iron pipe or pillar was erected, susceptible of
being lengthened as the Tower rose, by means of additional pieces of
pillar let in by _spigot and faucet joints_; and on the pillar a frame
of iron was placed capable of revolving freely round it, and carrying
two trussed arms and a double train of barrels and gearing. On the one
arm hung a cylindric weight of cast-iron, which could be moved along
it by means of the gearing, so as to increase or diminish by leverage
its effect as a counterpoise; and on the other was a roller. The roller
was so connected with the weight on the opposite arm, as to move along
with it, receding from, or approaching to, the centre pillar of iron in
the same manner as the weight did. From the roller hung a sheave, over
which a chain moved, with a hook at the end for raising the stones.
When a stone was to be raised, the weight and the sheave were drawn
out to the end of the arms of the crane, which projected over the
outside of the walls of the Tower, and they were held in their places
by simply locking the gearing which moved them. The second train of
gearing was then brought into play to work the chain which hung over
the sheave, and so to raise the stone to a height sufficient to clear
the top of the wall. When in that position, the first train of gearing
was slowly unlocked and the slight declivity inwards from the end of
the arms formed an _inclined plane_, along which the roller carrying
the sheave was allowed slowly to move (one man using a break on the
gearing to prevent a rapid run), while the first train of gearing was
slowly wound by the others, so as to take up the chain which passed
over the sheave, and thus to keep the stone from descending too low in
proportion as it approached the centre of the Tower. When the stone so
raised had reached such a position as to hang right over the wall, the
crane was made to turn round the centre column in any direction that
was necessary, in order to bring it exactly above the place where it
was to be _set_; and by working either train of gearing, it could be
moved horizontally or vertically in any way that was required. The men
who wrought the crane, stood on two small stages of planks attached to
either side of the framework, and moving round the shaft along with it.
The balance-crane was safely landed on the Rock on the 20th July and
on the 25th it was erected in working order on the top of the masonry.
On the afternoon of that day, I had the satisfaction of seeing it put
to a severe trial in raising a stone of nearly two tons weight and
drawing it from the _shear-poles_ already noticed to the top of the
building. As that trial was made at an earlier stage of the works than
was originally intended, the Tower was of larger diameter than was
quite suited to the arrangements of the crane, which was consequently
subjected to the weight of the stone at the very point of the jib. I
felt no small anxiety as to the result, and had taken the precaution
to relieve the centre pillar or shaft, on which the crane swung, from
part of its burden, by means of a guy attached to a lewis-bat on the
top of the building; yet even with that aid, the point of the jib was
depressed 6 or 8 inches on a length of 14 feet. That test, however,
having been successfully passed and not the slightest trace of any
injury having been discoverable in any part of the crane, we continued
to work it with perfect confidence and in the most satisfactory manner
throughout the whole season until the close of the Rock operations for
the year on the 17th of August.
The mass of masonry built during the season was 30,300 cubic feet, a
quantity considerably more than double that contained in the Eddystone
and somewhat more than the mass of the Bell Rock. The whole was very
carefully _set_ and when gauged at the upper bed of each course was
found to preserve the diameter due to the height, according to the
calculated dimensions, within a fraction rarely exceeding ¹⁄₁₆th of
an inch. The height of the mass also, when measured, exceeded the
specified height only by _half an inch_. The mortar employed was
composed of equal parts of lime from the Halkin Mountain in North
Wales and Pozzolano; and I consider it if possible superior to that
produced from the lime of Aberdda. When we left the Rock this season,
two apartments were covered in and the third was nearly completed, as
will appear from the section (Plate III.) (on which the progress of the
several seasons is marked), and only about _one-third_ of the whole
Tower remained to be built.
Our last work on the Rock before leaving it for the season on the 17th
August, was to cover the balance-crane with a strong tarpaulin in order
to protect it as much as possible from the weather and also to make a
temporary lightning-conductor from the top of the building to the sea.
The extent of work done during the season of 1841 at the Rock, must in
a great measure be attributed to the advantage of steam attendance,
without which numerous favourable opportunities of landing materials
must necessarily have been lost, from the uncertainty which pervades
all the movements of sailing craft. The number of lighters towed out
and discharged at the Rock was 120; and it is remarkable that no
accident of importance occurred, although many risks were run, from
the breaking of warps while the craft lay moored to the landing quay
during heavy seas. I cannot omit in this place to record my sense of
the services rendered to the works by the late Mr James Heddle, who
commanded the steamer and who died from some consumptive disease soon
after the close of the season’s operations. Mr Heddle’s health had
been somewhat enfeebled towards the latter part of the autumn; and his
excessive exertions and continued exposure during his arduous service,
in some measure, I fear, hastened the crisis of his disease, which at
length terminated suddenly by the rupture of an abscess in the lungs.
Of his anxiety to forward the work, and his unwearied exertion in the
discharge of his harassing duty at Skerryvore, which frequently allowed
him less than twenty hours sleep in a week, I cannot speak too highly,
as I consider his intrepidity and zeal to have been one of the most
efficient causes of our success ever since the commencement of the
works on the Rock in 1839. Mr Heddle possessed attainments superior
to those generally found among persons in his walk of life and was in
every respect a most estimable man.