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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



fAl-GCST, 



never since ceased to shine from sunset to sunrise. At first the 

 only source of illumination was derived from tallow candles, 

 which were continued long after the far better method of lighting 

 by means of Argand burners had been extensively used. In 

 1807, at the expiration of a long lease, the Trinity Board came 

 into possession of the Eddystone lighthouse, in which they at 

 once substituted the oil lamps as they at present exist. The light 

 is revolving, in a period of one minute, and is visible, in clear wea- 

 ther, for 13 miles. 



The successive improvements in the mechanical operation of 

 lighting introduced during this period may be thus recapitulated. 

 V\> to 178+, open fires of coal, wood, or pitch, were generally used; 

 in some few instances a system of tallow candles, protected by 

 glass frames, being substituted. In that year M. Argand invented 

 the oil-lamp known by his name. JM. Borda, very shortly after- 

 wards, contrived to adapt the invention to lighthouses. The 

 Trinity Board were not insensible to the value of this discovery. 

 A deputation, consisting of the deputy-master and several of the 

 brethren, visited France to inspect the results, and reported so 

 favourably, that it was speedily adopted in this country, and ex- 

 tended to Scotland and Ireland. In 1789, the suggestion of Buffon 

 and Condorcet, for the manufacture of glass lenses of large diame- 

 ters, was adopted for a lighthouse in the Isle of Portland; but, 

 owing principally to the imperfect state of the glass manufacture, 

 was found impracticable. In 1811, Brewster invented the method 

 of building large lenses in segments or zones of separate pieces, 

 and recommended the adoption of these infracting or "dioptric" 

 glasses in lighthouses. Notliing was done, however, until Fresnel 

 set the example eleven years afterwards in France, where the ma- 

 jority of lights are now constructed upon that system. Only a 

 few, comparatively, of the British lighthouses have to the i)resent 

 day abandoned the use of the reflectors, or "catoptric" lights. 

 Yet the relative power of the dioptric lamps is two to one, and its 

 economy nearly three to one over the reflecting burners, and they 

 transmit no less than 360 times the light of an unassisted flame. 

 On the other hand, there is some additional cost in the first erec- 

 tion of the lenses. Some attempts have been made to employ the 

 still higher illuminating powers of coal gas; but hitherto the dif- 

 ficulties have not been surmounted. The diief obstacle is in the 

 danger of fire and the liability of disorder in the apparatus, which 

 has to be reduced to a small compass within the narrow limits of 

 the light-towers, and entrusted too often to the custody of men 

 who are incompetent to conduct the operation. Nevertheless, gas 

 was used in a lighthouse at San Salvore, on the coast of Istria, as 

 early as 1818, and found to give a better light than oil, with a saving 

 of !)00 florins a-year. It was also employed in the Dantzic tower, 

 which had formerly been lighted by an open fire of coal, consum- 

 ing three times as much as the gas apparatus. \V^ax candles were 

 afterwards employed in the same lighthouse, and 1080 lb. weight 

 burnt in a year. Oil flames urged with oxygen gas, and the bril- ' 

 liant "Drummond" or lime liglit, were subsequently subjected to 

 experiments, with a view to their introduction as sea lights. But 

 the same mechanical difliculties and dangers stood in the way of 

 their adoption, and it was further discovered that a light from a 

 small luminous point, however brilliant, was not so appropriate as 

 that from the extensive surface of the Argand burners, of which 

 no less than 24 were sometimes used in a single lantern. Sir 

 David Brewster also proves that the ordinary quantum of light 

 from the oil lamp is quite sufficient for all maritime purj)oses in 

 clear weather. Yet the lime light, which casts a distinct shadow 

 at 18 miles distance, might be advantageously introduced as an 

 assistant in hazy weather. At present the obscurity of fogs is com- 

 pensated as far as possible by gongs, bells, and guns, which are 

 rung and fired at intervals from the beacon towers. 



As the lighthouse stations multiplied, it became necessary to 

 contrive some distinguishing mark by which the pilot might deter- 

 mine the one he sought. Various forms and clianges of the light 

 H ere, therefore, introduced, accomplishing nine varieties — viz., the 

 fixed white, revolving white, revolving red and white, revolving 

 red and two whites, revolving white and two reds, flashing, inter- 

 mittent, double fixed white, double revolving white. As the red 

 rays penetrate little more than half as far as the white, no light 

 must consist of red alone, especially as even white will look red 

 through a dry haze. The other colours are less penetrating still, 

 aiul therefore wholly unfit. According to the rule laid down by 

 I\Ir. Stevenson, no two lighthouses within 100 miles of one another 

 should have the same characteristics. The catastrophe of tlie 

 Gnvf Britiiiii steamer is a sufficient evidence of the necessity of 

 observing this rule, as it arose solely from a misapprehension of 

 the light on tlie Calf of Man. Now that lighthouses are becoming 

 so thickly multiplied, even the nine variations we have mentioned 



become insuflScient; and efforts are making to invent means for 

 making numeral figures visible at great distances when traced in 

 light. Already it is stated that the numbers can be distinguished 

 at a distance of 12 miles. 



A parliamentary committee was appointed in 184.4, chiefly by the 

 perseverance of ^Ir. Hume, to investigate the condition and ad- 

 ministration of the British lighthouses, and published a volumi- 

 nous report as the result of their labours. As usual, great mis- 

 management was proved to exist, combined with an uncertainty 

 and inconsistency in the charges and tolls levied upon shipping, 

 which must have occasioned considerable injury to our commerce. 

 The worst results, however, were found to arise from the system 

 of private management which still existed, either under old grants 

 from the Crown, or in virtue of some very inconsiderate leases by 

 the Trinity Board. The private ovrners in all cases thought only 

 of making a large revenue from their monopoly, and in many in- 

 stances had omitted to adopt the improvements in lighting univer- 

 sally employed elsewhere, and had occasioned some severe losses of 

 shipping l)y their criminal negligence. There was one light-tower 

 in the Isle of Man, on the Scotch coast, which belonged to the 

 Duke of Portland, and so late as the year 1810 was lighted by the 

 primitive contrivance of an open coal fire. In that year, two fri- 

 gates of the royal navy, the Pal/as and the Juno, mistook for this 

 light the flame from a lime kiln on the shore of East Lothian, and 

 were lost in consequence. Several lives were sacrificed, besides 

 the two ships, which were worth 200,000/. The lighthouse has 

 since passed into the keeping of the commissioners of northern 

 lights, and is provided with tlie proper Argand and reflecting ap- 

 paratus. The purchase money paid to the duke, together with the 

 outlay requisite for the introduction of an improved system of il- 

 lumination, amounted to 70,452/. Proofs of inattention, less in 

 degree but equally unjustifiable, were discovered in other light- 

 houses under private management. It was proved also that wliile 

 the costs of ^maintenance were far less than in the navy lights 

 erected by the Trinity Board, the revenues collected were per 

 light somewhat superior, and the net income to the proprietors 

 and lessees 60,392/. per annum, drawn from the commerce of the 

 country. 



Some curious anomalies were also exposed in the levying of tolls 

 on vessels, for the supposed advantage of tlie lights. Thus, 

 throughout England a duty of ^il. to \^d. per ton was levied on 

 every vessel passing a lighthouse, the rate varying with every 

 light, which had its distinct rules and system of collection. In 

 Scotland, on the other hand, a ship that passed one light paid a 

 certain rate per ton for the whole number, and no more, if it went 

 the entire circuit of the coast. In the voyage from Leith to Lon- 

 don, therefore, a vessel of 142 tons would pay 1/. 9.s. l^i. for the 

 Scottish lights, though it passed only one of them; and would 

 have 4/. 17.?. 3f/. charged for the 19 English lighthouses passed be- 

 tween Berwick and London. A Yarmouth vessel also, bound for 

 the Thames, but driven by stress of weather to the Frith of Forth, 

 would pay for the whole series of Scotch lights, though it had used 

 none, having only been driven into their waters. In Ireland, the 

 charge was made at certain rates on the tonnage of every ship en- 

 tering an Irish port, whether it had passed a lighthouse or not. 



In consequence of the report of the committee in 1834, the act 

 6 and 7 William IV. was passed. Under this statute all the pri- 

 vate rights in lighthouses were extinguished, and bought up by 

 the Trinity-house at a cost of no less than 1,182,546/., such was 

 the presumed value of these indispensable monopolies. Of this 

 sum Mr. Coke had 20,900/. for Dungeness lighthouse, and Lord 

 Braybrooke 37,896/. for the one on Orford Point. Tlie Small's 

 light cost more than four times as much — 170,468/. But the 

 worst instance was that of the Skerries lighthouse in the Irish 

 C'hannel. Queen Anne had granted a patent, in 1715, to Sutton 

 French, Esq., to erect a ligiit-to«er oft' tlie coast of Anglesea, for 

 the benefit of tiie Irish sliippiiig, and levy a toll of \d. per ton on 

 all passing vessels, in recompense of the same. The ininieiise in- 

 crease in Irisli commerce had rendered this light incredibly pro- 

 fitable, as it was kept up at a cost, probably, of under 500/. per 

 annum, and the returns were over 20,000/. For a long time Mr. 

 Morgan Jones, the reiiresentative of the first possessor, resisted 

 all the efforts of the Trinity-house to make him surrender his 

 claim, or even furnisli any account of his receipts, alleging that 

 his patent was granted in perpetuity, and witliout rent or fee to 

 the Oown or other autliority. The stringency of the late act, 

 however, compelled a production of the accounts, and after much 

 litigation a jury assessed the compensation to Mr. Jones at 

 441,980/., being 22 years' purchase of 20,042/. annum revenue. 

 This transaction closed in 1842, and since then all the English 

 coast lights are under the management of the Trinity-house, and 



