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CHAPTER XVII. EXTRACTS FROM EARLY REPORTS.
    Wide range of subjects on which Mr. Stevenson gave advice—Reports on ruins of Aberbrothock Abbey—St. Magnus Cathedral, and Earl’s Palace, Kirkwall—St. Andrews Cathedral—Montrose Church Spire—Melville Monument, Edinburgh—Lipping of joints of masonry with cement—Provision for flood waters in bridges—Hydraulic mortar—Protection of foreshores—Cycloidal sea wall—Checking drift sand—Night signal lamps—Cause of heavy seas in Irish Channel—Sea routes across Irish Channel—Build of ships—Prospective increase of population—Tidal scour—Unscrewing of bolts by the waves—Cement Rubble cofferdams—Buoyage system—Observations on fog signals—Regulations for steam vessels—Notes on shipwrecks.

Judging from Smeaton’s well known “Reports,” to which all have access, we may conclude that the “professional advice” given by early Engineers was very generally accompanied by a fuller and less reserved discussion of opinion than is to be met with in the brief and technical Engineering reports of the present day. In early times, Engineers did not hesitate to express themselves freely on physics, ?sthetics, or commerce, provided their views had a collateral bearing on the subject under discussion, and this often added to the interest of their reports.

These early Engineers were also consulted on a much wider range of subjects than the Engineers of modern times. We know that the larger requirements of modern Engineering demand that its practice should be classified237 under distinct branches, such as harbours, navigations, water works, gas works, lighthouses, or railways, not to mention electrical and sanitary engineering, and other branches of modern growth, all of which cannot possibly be advantageously practised by any one member of the profession; for no one mind can grasp the theoretical knowledge, and no one life can compass the practical experience, to enable a man to attain eminence in all these departments of modern Engineering.

A biographical sketch of Mr. Stevenson’s professional life would, it seems to me, be incomplete if it did not convey to the reader some notion, however general, of the wide range of subjects brought under his notice, in these early times, and of his comprehensive and suggestive mode of treating every case on which he was professionally consulted. This object would be only imperfectly attained were I to restrict my reference to his reports to the examples given in the preceding chapters; for I have found in his numerous writings casual notices of a miscellaneous and fragmentary character, many of which seem to me to be interesting to the profession, and worthy of preservation, and I propose, in this chapter, to give a few of these extracts, without order of subject or date; and I think they will justify my remark as to the great variety and fulness of treatment to be found in the reports of early Engineers.
* * * * *

It appears, for example, that Mr. Stevenson was often called to advise on matters which were more related to architecture than engineering. Of this nature was his238 tour of inspection to the jails of England, in company with Sir William Rae, the Sheriff of Edinburgh, in 1813, referred to in a former chapter.
ABERBROTHOCK RUINS.

In like manner he inspected Aberbrothock Abbey, with Sir Walter Scott and the Sheriff of Forfar, in 1809, to advise as to preserving the ruins, some of the turrets being in imminent danger of falling; and after procuring a survey of the whole building he prepared a report, with plans and specification, which were submitted to the Barons of Exchequer, and the work was thereafter carried out under his direction.
ST. MAGNUS CATHEDRAL AND EARL’S PALACE.

He also reported in a similar way to the Sheriff of Orkney with reference to the repairs of the Earl’s Palace at Kirkwall, estimated at £500, and on certain alterations at the Cathedral of St. Magnus.
ST. ANDREWS CATHEDRAL AND MONTROSE SPIRE.

With a similar object in view he inspected and reported on the Cathedral of St. Andrews, and the steeple of the Church of Montrose, which was thought to be in danger, and the result of that inquiry was the present beautiful spire, built from the designs of James Gillespie Graham.
MELVILLE MONUMENT.

He was also associated with Mr. Burn in the Melville Monument of Edinburgh,—the preparation of the foundation,239 the rubble work for the tower, and the scaffolding and tackling for raising the statue were carried out under Mr. Stevenson’s direction; the whole architectural design being due to Mr. Burn alone.
LIPPING OF JOINTS OF MASONRY WITH CEMENT.

The well known practice of what is termed “lipping” with cement the mortar joints of masonry exposed to the wash of water is described by him as new in his report to the Trustees of Marykirk Bridge, of 16th July 1812, where he says:—

“Upon carefully examining the face joints of the masonry of the south pier under water line, some of these were found not to be so full of mortar as could have been wished, and although Mr. Logan (the inspector of works) had taken the precaution to cause the joints to be covered with clay to preserve them from the effects of the water, yet this had not altogether answered the purpose, and hence the reporter recommended to the meeting of the 8th current to provide a few casks of Parker’s Roman Cement, to be laid to the breadth of three or four inches upon the bed and end joints under the low water mark of the remaining piers.”
PROVISION FOR FLOOD WATER IN BRIDGES.

In determining the waterway of his bridges, Mr. Stevenson invariably provided for prospective increase of flooding due to agricultural improvements, as stated in the following extract from a report made in 1811:—

“To preserve an ample waterway the north abutment is placed about twelve feet from the edge of the river,240 leaving a sufficient passage for the water in floods. A less waterway might perhaps have answered the purpose, but as the valleys through which the North Esk passes may come to be meliorated by drainage, and especially those districts of country on each side of the feeders which join the river, the facility with which the surface water may then escape must greatly increase the floods, and although their duration will be shorter, yet their rise must be proportionally higher.”
HYDRAULIC MORTAR.

The following remarks on hydraulic mortar, made in 1811 to the Commissioners of Montrose Bridge, are interesting as showing the detail which he brought to bear on all his works:—

“The best mortar for water work is a mixture of Pozzolano earth with lime and sand, but the late interrupted state of commercial intercourse with the Mediterranean has for years past rendered Pozzolano so scarce an article as hardly to be procured on any terms. Your reporter has therefore been induced to make various experiments with preparations of lime and Roman cement, and finds that a mixture may be made which will set under water and answer every purpose. For this mortar the lime ought to be well burned, and put into casks when drawn from the kiln. It should be brought to the work as recently after being burnt as possible. This will be most readily attained by taking the lime from Boddam kilns. English lime is in general stronger and cleaner, but some of it brought for the purpose of241 agriculture is not so suitable for buildings as Lord Elgin’s lime. These limes, however, cannot be had very newly burnt, and it will be preferable to take lime from some of the kilns in the neighbourhood which are of good character. When brought to the bridge the lime should be kept under cover, opening only one barrel at a time; the shells must be pounded to a state of powder, and immediately before mixing it with the other ingredients it will be proper to sprinkle a little water upon it to dissolve any gritty particles that may remain amongst it.

“The sand for this work, though fine, must nevertheless be sharp; it must also be passed through a sieve, and cleaned of all impurities by washing, if found necessary. For ramming the joints and pointing under water, let equal parts of lime in its powdered state and of Roman cement be used, with one fourth part of prepared sand, but for the upper works the quantity of Roman cement in the mortar may be reduced to one third part.

“The mortar must be mixed in small quantities and quickly beaten up into a consistency suitable for the work. All white specks, which are apt to swell and spoil the joints, must be carefully rejected from the mortar.”
PROTECTION OF FORESHORES.

Some suggestive remarks on the protection of foreshores, made in 1812, in a report to Lord Rosebery, on his Lordship’s property at Barnbougle Castle on the Firth of Forth, are given in the following terms:—

“If the operation of the waters of the ocean be242 attended to in the formation of the shores, some useful hints may be gained. These shores will be found to be so many inclined planes, varying in declivity according to the tenacity of the matter of which they, are composed. Hence it is that the minute grains of sand and the light sea shell become a lasting barrier against the rapid river current and the tumultuous ocean, while the erect sea wall is levelled with the ground. For the truth of this it were needless to refer to the works of nature in different quarters of the world, or in distant parts of this country; it is only necessary to examine the shores on each side of Barnbougle Castle, where the beautiful beach, consisting of sand and shells, between the Cockle Burn and the sea, forms a complete defence to the low grounds behind it, while to the northward of the castle the massive wall is in danger of being completely thrown down. Without waiting to inquire into the causes which regulate these appearances, it will be more consonant to the business of this report to point out how their simple forms may be imitated and turned to advantage.”
CYCLOIDAL SEAWALL.

In reporting on the defence of the lands of Trinity, on the Firth of Forth, Mr. Stevenson recommended the adoption of a cycloidal talus wall, which was executed under his direction in 1821:—

“In giving an opinion relative to the best mode of defending and preserving this property, the reporter observes that it fortunately happens that the beach is pretty closely covered with large boulder stones, which now form a kind of chevaux de frise in breaking the force243 of the sea, and making it fall more gently towards high water mark. Were it not that these stones are proposed to be employed in the erection of a more effectual barrier against the waves, the reporter would not fail to disapprove of their removal for any other purpose.
Fig. 20.

“The reporter proposes that a Talus wall or bulwark should be built of these boulder stones, roughly dressed and laid so as to form a cycloidal curve in the central part, as nearly as may be, as represented in the section with its tangents (Fig. 20). The properties of the cycloid as applicable to a sea wall in an exposed situation are very important. In particular, if compared with any other curve, in the same vertical line and down through the same points, it will be found of swiftest descent under similar circumstances, therefore the water in its rise must be proportionally retarded. The lower tangent to the curve alluded to also forms a wall towards low water, best adapted for admitting the sea to flow gently over it, while that connected with the upper extremity of the cycloidal part, tending towards the perpendicular, brings gravity into action against the rise of the waves.244 The practical execution of a wall upon this construction is simple, while the aggregate quantity of materials is less than for any of the curves of the conic sections of similar extent, and it seems upon the whole to be peculiarly applicable for the defence of the sea beach in question.

“If we examine the numerous works of this kind erected for similar purposes along this coast, we shall find that the general process or action of the waves is to undermine the seaward courses of the walls. In some cases, however, where due attention has not been paid to making up the backing of the face wall in a compact and firm manner, the central parts have been found to sink and give way. But the more common mode of failure is by the undermining of the seaward courses, arising from too sudden a slope being given to the face wall, which has a direct tendency to produce additional agitation in the waters at the bottom of the wall, by which the beach is excavated, and the foundation, being exposed to the wash of the sea, its destruction soon follows. If we attend to the distribution which nature makes of the matters composing a sea beach, unless where special local causes occur, we find them laid with a very gradual descent towards low water mark. The sands of Portobello, in this neighbourhood, form a striking example of this. Here small quartzose grains mixed with light sea shells prove, in their effects, a more effectual barrier against the overwhelming force of the waves than perpendicular and massive walls of masonry.”

245
CHECKING DRIFT SAND.

Mr. Stevenson recommended Lord Palmerston to introduce the Pinus maritima major, as a check for sand drift, on his estate of Mullaghmore, in the following report, dated 21st July 1835:—

“During the reporter’s visit to Mullaghmore, his advice was also asked regarding the operations at present going on for the improvement of the land. He had then much satisfaction in viewing the interesting improvements of reclaiming bog lands, and checking the inroads of the sand flood or drift, by planting ‘bent’ grass upon the shores of this estate. The system of dibbling the bent grass, pursued by Mr. Lynch, is in the best style which the reporter has anywhere met with; and he has been so impressed with the national importance of this scheme, from the success already experienced at Mullaghmore, that he has already taken the opportunity of recommending this system as applicable to the entrance of Ballyshannon, and in other quarters, particularly to the Highland and Agricultural Society of Scotland.

“The question chiefly submitted to the consideration of the reporter, in regard to these operations, was the best mode of defending the margin of the bent grass towards the sea. For such purposes, buildings or fences of any kind are not only expensive in their formation, but are also in constant need of repair. Mr. Lynch seems so much at home in all planting operations that the reporter begs simply to bring under your Lordship’s notice the French mode of planting a species of fir (Pinus maritima major),246 which was originally suggested to the Government by the late M. Bremonteuil, Ingénieur des Ponts et Chaussées. This system has been extensively tried along the stormy shores of the Bay of Biscay, particularly in the district of Grave, at the entrance of the Garonne, where the arid and sterile sands have been covered with extensive forests, which thrive quite close to the water’s edge. From the climate and exposure of the shores at Mullaghmore, the reporter has no doubt of the success of similar plantations in arresting the progress of the sand flood. It is believed that Mr. Lawson, seedsman to the Highland and Agricultural Society of Scotland, is taking measures to import the seeds of the Pinus maritima major, with a view to trying it on some of the exposed sandy districts of Scotland.”

From the following extract of a letter from Mr. Kincaid of Dublin, who was Lord Palmerston’s Commissioner, it is interesting to know that the experiment was entirely satisfactory, proving that the Pinus maritima major is well adapted to the climate of the coasts of the British Isles:—

“The Mullaghmore plantations extend to about 200 acres. About eighty of these were planted twenty-five years ago. Some of the trees are thirty feet in height, and vary from that height to about twenty or twenty-five feet. The remainder were planted ten years ago, and are making fair progress. All the pine plantations from opposite Newtown Cliffony to Mullaghmore are in a most healthy condition, the trees making growths of from twelve to twenty inches each year. The storms have no bad effect on the south side of the great sand hill, but on its summit, and towards the west side, the spray and247 gales of the Atlantic will not allow the young trees to make any progress.”
NIGHT SIGNAL LAMPS.

In a report to the Trustees for improving the Queensferry passage, made in 1811, Mr. Stevenson proposes a set of signals as described in the following extract, his proposal being, in fact, the signal now in use on all British railways:—

“Upon the supposition of its being the intention of this Honourable Trust to have an establishment on the south side of the Firth similar to that which is now proposed for the north side, the reporter takes the liberty of observing that much advantage, as the Trustees know, might be derived by the public from a few simple and well appointed signals, both for night and day.

“Those intended for the day may be constructed upon a modified scale, after the common telegraphic method; while the night signals can be rendered extremely simple and effective by interposing at pleasure between the observer and the reflector a shade of coloured glass. By connecting these partial obscurations of colouring the light with an index that shall be understood on both sides of the passage, orders may be communicated in a very expeditious manner.”
CAUSE OF HEAVY SEAS IN IRISH CHANNEL.

In a report to the Right Honourable Viscount Cathcart, Commander of His Majesty’s Forces, made on Portpatrick harbour in 1812, he gives the following explanation of the well-known rough sea between Portpatrick and Donaghadee:—

248 “In describing the harbour of Portpatrick, it may be noticed that although the coast on which it is situated is not directly exposed to the Atlantic Ocean, yet the opposing tides of the north and south channels meet there and separate to flow up the Clyde and Solway Firths, which, independent of storms, must occasion a very considerable commotion in the waters of the channel between Portpatrick and Donaghadee.

“Accordingly we find that the sea has made a great impression upon the coast of Wigtonshire; and though the shores between Loch Ryan and the Bay of Glenluce consist chiefly of whinstone (the greenstone of mineralogists), which is one of the most indestructible rocks we have, yet the figure of the coast is indented with many small cuts or creeks, and rocks are all along the shore found jutting into the sea. At the head of one of these creeks, which is about a hundred fathoms in length, and thirty fathoms in breadth, the harbour of Portpatrick is situated between two insulated rocks, upon one of which the piers are built, the harbour being formed by an excavation, chiefly in the solid rock.”
SEA ROUTES ACROSS IRISH CHANNEL.

In the same report he states the relative advantages of various routes of communication across the Irish Channel:—

“A further extension of the intercourse between Scotland and Ireland could be made with much advantage to both by a regular establishment of packets between Ardrossan, Troon, or Dunure in Ayrshire, and Larne in the county of Antrim. Between the two last places,249 viz., Dunure and Larne, the distance would only be about sixty miles, being ten miles shorter, and unquestionably much safer, than the passage from Holyhead to Dublin.

“Under all the views of this subject, from the greater contiguity of Portpatrick and Donaghadee than of Lochs Ryan and Larne, and the former places having more immediate access to the open sea than the latter, and also from the intercourse being now fully organised by long establishment, it were perhaps better, even at a much greater expense, to continue the present system than to change it. Portpatrick harbour may be rendered incomparably better by the plan now proposed, and Donaghadee is also capable and stands much in want of improvement, by an extension of its piers and the erection of a permanent light to direct the packets into the harbour under night.”
BUILD OF SHIPS.

In reporting to the Royal Burgh of Dundee as to the improvement of the harbour in 1814, Mr. Stevenson takes occasion to introduce one of those collateral questions to which I have referred:—

“It is curious to observe the changes and to trace the progressive improvements which have taken place in the form and build of ships. When we contrast those of early navigators with ships of modern times, among the many alterations, none seems more striking than the difference of their depth. The draught of water that was required for a ship of 300 tons burden would hardly be found enough to float a modern built vessel of 100 tons.250 This alteration in the construction of ships, which is mainly calculated to improve their sailing, by giving them a better hold of the water, seems gradually to have advanced, as the mariner became more adventurous in his voyages; and is only now restrained by certain considerations of convenience, of which the most prominent is the want of a sufficient depth of water in the havens and harbours on the coast for their reception,—a circumstance which arises partly from the natural position of harbours, but is chiefly owing to the difficulties and expense attending the necessary engineering operations, which increase enormously with the depth of water. Hence it is that many of the ancient seaport towns of this country, which at one time possessed an extensive trade, have, from neglecting their harbours, sunk into a state of insignificancy; while others, by proper exertions in this respect, have, under the most inauspicious circumstances, attained to great commercial importance.”
PROSPECTIVE INCREASE OF POPULATION.

Another case of the same kind occurs in his report on the harbour of North Berwick, made in 1812:—

“Before closing this report it may be noticed that North Berwick has considerable advantages, which if acted upon would infallibly lead to the rapid improvement of the town and neighbourhood. Situated upon an extensive flat which skirts along the high land of North Berwick Law, on a beautiful sandy bay, which is intersected by the street leading to the harbour, few251 towns will more easily admit of elegant extension or are better calculated for becoming a sea-bathing retreat.”

It has now the well-known reputation of being the best frequented watering place on the east coast of Scotland.
TIDAL SCOUR.

In the report, of 1814, on Dundee we find the following remarks on tidal scour:—

“To put this matter in a clearer point of view, let us see what nature does upon the great scale, as for example in the extensive basin forming the Firth of Tay. We there find that in consequence of the rapidity of the current at the narrow passage in the neighbourhood of Broughty Castle, which may be viewed as the scouring aperture of the basin of the Tay, the water is from forty to eighty feet in depth, and moves with a velocity which carries a great quantity of sandy particles along with it. But no sooner are the waters of this current allowed to spread and cover the basin of the Tay, than the velocity ceases, and the foreign matters fall to the bottom and form the various sandbanks which appear at low water. In a similar way the deposition of silt and earthy particles brought down the river in speats is accounted for. Now, this view of the case is equally applicable to the harbour of Dundee, for so long as the water preserves the velocity it acquires in the scouring apertures or arches in the quays, it carries all its foreign matters along with it; but the moment it is allowed to expand over the extent of the harbour the deposition of these earthy particles begins.252 And in every case the well-known law in hydraulics holds good, that the scouring effect of a fluid is in the ratio of the square of the velocity.”
UNSCREWING OF BOLTS.

The following observations made in 1807 on the action of the waves in unscrewing bolts, are interesting:—

“The unlocking of screws, where washers had been introduced as a security was rather unexpected, and the writer took an opportunity of conversing with his much respected friend Professor Playfair regarding this circumstance. The Professor observed, that he had experienced some inconvenience of this kind from the unlocking of almost all the screws of a telescope which had been sent to him from London by the mail coach. Indeed, from the spiral form of the screw, which is, in fact, an inclined plane, Mr. Playfair readily accounted for such an occurrence, and, when reflected upon, it seems to be an effect rather to be looked for, and is a reason why riveting the point of a bolt in preference to screwing it should generally be resorted to, where much motion is to be apprehended.”
CEMENT RUBBLE COFFERDAMS.

I give his description of the cement rubble cofferdams, first used in 1808, at the erection of the Bell Rock Lighthouse:—

“At seven o’clock this morning, the tide proving more favourable, the artificers began to work. At nine o’clock the rock was again overflowed, and the boats253 returned to the tender after two hours’ work. Part of the operations of this morning’s tide consisted in building up the crevices and inequalities of the rock round the margin of the foundation with Pozzolano mortar and the chips produced from excavation, with the view to dam out the water. These little walls varied from six to eighteen inches in height; a small sluice or aperture being formed in one of them, by which the water, during ebb tide, was allowed to drain off.

“It formed part of the writer’s original design to erect a cast iron cofferdam of about five feet in height round the site of the building; but the surface of the rock was so irregular that the difficulty of tightening it, and also of emptying the contained water, so as to get the benefit of it during ebb tide, would have been so great, that taking these circumstances into account, together with the loss of time which would attend the erection of such a preparatory work, the idea of a cofferdam was laid aside, soon after entering upon the actual execution of the work.”
BUOYAGE SYSTEM.

In his report on the Forth Navigation, made to the Magistrates of Stirling in 1828, Mr. Stevenson proposed a system of buoyage, which has since been adopted by the several Lighthouse Boards of the United Kingdom:—

“The channels proposed to be cleared through the different fords are coloured red on the Plan, in reference to the sectional line. For the use and guidance of river pilots, buoys and perches or beacons are likewise intended254 to be placed in the positions shown in the Plan; those coloured red are to be taken on the starboard, and those coloured black upon the larboard side, in going up the river; and the whole are to be so placed in connection with the clearing and deepening of the fords as to be approached with safety.”
OBSERVATIONS ON FOG SIGNALS.

At a very early period Mr. Stevenson’s attention was directed to the dangers of fog at sea, and the best means of providing an effective fog signal for the mariner, and so long ago as 1808 he had come to the conclusion that the best signal adapted for the purpose was the sustained sound of a horn, which, as is well known, has within the last few years been so much employed in the fog signals which are now being established at many of the lighthouse stations in this and foreign countries. The following extracts give an idea of the difficulties he encountered, and his views on the subject:—

“The boats landed this evening (23d June 1808), when the artificers had again two hours’ work. The weather still continuing very thick and foggy, more difficulty was experienced in getting on board of the vessels to-night than had occurred on any previous occasion, owing to a light breeze of wind which carried the sound of the bell, and the other signals made on board of the vessels, away from the rock. Having fortunately made out the position of the sloop “Smeaton,” at the north-east buoy, to which we were much assisted by the barking of the ship’s dog, we parted with the Smeaton’s boat, when the255 boats of the tender took a fresh departure for that vessel, which lay about half a mile to the south westward. Yet such is the very deceiving state of the tides that although there was a small binnacle and compass in the landing master’s boat, we had nevertheless passed the ‘Sir Joseph’ a good way, when fortunately one of the sailors caught the sound of a blowing horn. The only fire-arms on board were a pair of swivels of one inch calibre; but it is quite surprising how much the sound is lost in foggy weather, as the report was heard but at a very short distance. The sound from the explosion of gunpowder is so instantaneous that the effect of the small guns was not so good as either the blowing of a horn or the tolling of a bell, which afforded a more constant and steady direction for the pilot. It may here be noticed that larger guns would have answered better, but these must have induced the keeping of a greater stock of gunpowder, which in a service of this kind might have been attended with risk. A better signal would have been a bugle horn, the tremulous sound of which produces a more powerful effect in fog than the less sonorous and more sudden report of ordnance.”

And again he says:—

“In the course of this morning’s work two or three apparently distant peals of thunder were heard, and the atmosphere suddenly became thick and foggy. But as the Smeaton, our present tender, was moored at no great distance from the rock, the crew on board continued blowing a horn, and occasionally fired a musket, so that the boats got to the ship without difficulty. The occurrence256 of thick weather, however, became a serious consideration in looking forward to the necessary change of quarters to the Pharos, distant about one mile from the rock, instead of a few hundred yards, as in the case of the Smeaton.

“The weather towards the evening became thick and foggy, and there was hardly a breath of wind to ruffle the surface of the water; had it not therefore been the noise from the anvils of the smiths, who had been left on the beacon throughout the day, which afforded a guide for the boats, a landing could not have been attempted this evening, especially with so large a company of artificers. This circumstance confirmed the writer’s opinion with regard to the propriety of connecting large bells to be rung with machinery in the lighthouse, to be tolled day and night during the continuance of foggy weather, by which the mariner may be forewarned of too near an approach to the rock, while every distant object is obscured in the mist.”

Following out this subject, Mr. Stevenson caused observations to be made at the Calf of Man—a small island at the south of the Isle of Man, and separated from the main island by a narrow “sound.” The place is noted for its fogs, on which Mr. Stevenson says:—

“I sent Mr. Macurich, a shipmaster in the lighthouse service, to the Calf of Man, with directions to reside there, and make monthly returns of the state of the weather, agreeably to a printed form. During his stay of seven months, it appears upon the whole that the fog rested only twice upon the highest land of the Calf Island, while257 it cleared partially below. On one of these occasions I was on board of the lighthouse yacht, then at anchor off the island, when the fog was for a time general; and as the weather became clear, I observed that it first disappeared upon the lower parts of the island, and that in half an hour the whole of the Calf was seen. In the monthly returns made by Mr. Macurich, the Calf island is represented as often perfectly free of fog, while the higher parts of the opposite mainland of the Isle of Man were hid in mist. To account for this, it may be noticed that the mass of matter in the Calf Island is much less, and the land is also much lower than in the main island. Part of this effect may also be ascribed to the rapidity of the tides, which create a current of wind, particularly in the narrow channel between the main and Calf islands, which have a direct tendency to clear away the fog, as I have observed at the Skerries in the Pentland Firth, and in similar situations on different parts of the coast, where rapid currents prevail.”

These extracts are given to show the attention Mr. Stevenson gave to the subject of fogs, which, as already noticed, led him to recommend the horn, the instrument now so much used in giving signals to the mariner.

Akin to this may be mentioned his expression of regret that no means existed for determining the force of the wind, as noticed in the following paragraph:—

“We cannot enough regret the want of an efficient anemometer, or instrument for measuring the force of the wind. Indeed, we hardly know any desideratum of more universal interest, for, notwithstanding the labours of258 Lind and others on this subject, from the want of a proper scale we are still groping in the dark with the use of such indefinite terms as ‘light airs inclining to calm,’ ‘fresh breezes,’ ‘fresh gales,’ ‘hard gales,’ and ‘very hard gales;’ for it rarely happens that the sailor will admit the term ‘storm’ into his nomenclature.”
REGULATIONS FOR STEAM VESSELS.

The loss of the ‘Comet’ steamer by collision on the Clyde, in 1825, led the Lord Advocate to entertain the idea of introducing a Bill for the regulation of steamers, and to issue a circular in the following terms, of which Mr. Stevenson received a copy:—

    “Edinburgh, 4th Feby. 1826.

    I annex a copy of the heads of such a Bill as, in my opinion, may be calculated to afford sufficient security to steamboats, and thereby alike promote the interests of the owners of such vessels and that of the public. I feel noways wedded to any of the proposed provisions, and am anxious to submit them to the consideration of the better informed on such subjects, so as to obtain suggestions either as to the additions or amendments which the Bill may be fitted to receive.

    “In directing your attention to this important subject, I need hardly remind you that in our endeavours to render such vessels perfectly secure in so far as respects the passengers, we must not lose sight of the interest of the owners, or attempt to clog the trade with unnecessarily embarrassing regulations. Such restrictions are259 seldom enforced, and, if they should receive effect, might lead to such harassing consequences as would injure this useful description of property, and thereby to a certain extent deprive the public of the great benefit which is now derived from the use of vessels navigated by steam.—I have the honour to be your most obedient servant,

    “Wm. Rae.”

The only account I can find of Mr. Stevenson’s views on this important subject is contained in the following extract from a letter, dated 3d November 1825, to Captain Foulerton, one of the Wardens of the Trinity House, with whom he appears to have had much correspondence, in which he explains views which are very much in accordance with the regulations for steamers now issued by the Board of Trade. His letter says:—

“We lately had a melancholy accident, as you would see, by the running down of the ‘Comet’ steam packet, by which, it is believed, that about seventy people lost their lives. The Lord Advocate attended himself at the taking of the precognition, and is, I believe, to bring some of the parties to trial. He has also in view some regulations by an Act on this new and important subject.

“From my seeming marine habits his Lordship has desired me to state what occurs on the subject of lights. If we need this on the Forth and Clyde, you must be in a worse state in the Thames. I have no doubt you had this under the notice of your House. I think there should be two lights, one in each bow, but under deck, in order to keep the lights entirely out of the view of those on260 deck. I am not for interfering with their head sails. I would have them licensed like stage coaches, and placed under the inspection of an officer of the navy, not below the rank of a lieutenant. Six or eight officers might do the duty for the whole United Kingdom for a time.”

The accident seems to have led to a further investigation into the general question of the saving of life in cases of shipwreck on the coasts of Scotland; and on this subject Mr. Stevenson made the following replies to the queries submitted to him by the authorities:—

    “Query.—Are shipwrecks frequent on the coasts of Scotland and its islands?”

“Wrecks between the Firths of Forth and Moray are more frequent than on any other part of the coast of Scotland. This may probably be accounted for by the great number of vessels passing and repassing along that coast. In the month of December 1799, a strong gale from the south-east occasioned serious disasters on these shores, when upwards of seventy sail were wrecked on the eastern coast of Scotland, and many of their crews perished. This lamentable catastrophe was the means of causing lifeboats upon Greathead’s plan to be fitted out at St. Andrews, Arbroath, Montrose, Aberdeen, Peterhead, and other places, which have been found highly useful in saving the lives of mariners. This gale was also the immediate cause of the erection of the Bell Rock Lighthouse, which may be said almost entirely to have prevented shipwreck, so frequent in St. Andrews Bay and the entrance of the Firth of Forth in general.

261 “From the Moray Firth along the shores of the mainland to the entrance of the Firth of Clyde, wrecks cannot be said to be very frequent, although the navigation is rather difficult; but the safety of shipping on this coast depends upon the great number of excellent natural bays and harbours upon it.

“In the Orkney and Shetland Islands few seasons pass without wrecks occurring. On the Lewis and Western Hebrides shipwrecks frequently occur.”

    “Query.—Are the coasts of Scotland in general well provided with the means of giving assistance in case of shipwreck, or are they deficient in such provision?”

“The coast of Scotland is provided with no other means of saving the crews of vessels than the assistance they accidentally meet with from the inhabitants along shore. The only lifeboats established are those at the ports already mentioned.

“If Captain Manby’s apparatus was generally known and applied upon the coast, it would be found highly beneficial.”

    “Query.—Are any instances remembered of total shipwrecks where lives lost might have been saved by the lifeboat or by Captain Manby’s apparatus, at the distance of 350 or 400 yards off the coast?”

“In the year 1813 the ‘Oscar,’ Greenland ship of Aberdeen, Captain Innes, went ashore upon Girdleness, at the entrance of Aberdeen Harbour. There were on board fifty-four persons, of whom only two were saved, by262 dropping from the bowsprit end. The ship was very near the shore. She broke up about twenty minutes after she struck, and I have no doubt that, if an active person had been on the spot with Captain Manby’s apparatus, the greater part of the crew of this ship might have been saved.

“In the winter of 1824 the ‘Deveron’ of Aberdeen, Captain Scott, went ashore upon the sands three miles north of Aberdeen in a gale at south-east. She was only about 300 yards from the shore, and here the whole crew must have perished had it not been for the prompt use of Captain Manby’s apparatus.

“Every one who has seen this apparatus must have admired its simplicity and effect. It is however difficult to see how its application can be very generally introduced so as to be useful along the whole extent of chequered coasts of the British dominions. Certainly at all principal ports it would naturally be expected that both this and the lifeboat would be provided.

“A time seems to be approaching when the coast will be much more complete in all such provision from the hands of the humane for the safety of the mariner. We also hail with pleasure the extending efforts of the respective Lighthouse Boards on the coasts of England, Scotland, and Ireland, as a certain means of adding to the security of that useful body of men, as well as to the facilities of her enterprising merchants. Nor can we withhold the notice of the effect of the operations of the Scots Board in this respect. At the entrance to the Firth of Forth, prior to the erection of the Bell Rock263 Lighthouse, few winters passed without some disastrous shipwreck.

“Even after the completion of this arduous undertaking, until the beacon was erected on the Carr Rock, off Fifeness, the fisherman’s observation was—‘The Carr has always her wreck: if she misses one year, she is sure to have two the next.’ But since the erection of this beacon in 1820 till this date (1825), not a single wreck has happened on this part of the coast.”


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