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and considerable disbursement of the The effect of this very defective arpublic money in their immediate vicinity. rangement, may be seen by a glance at Petitions, of course, and a sense of his a chart on which the Light-Houses of the responsibility at the ballot-boxes, im sea board are marked. The New Engpress him with a similar conviction: and land coast, comparatively safe and wellit becomes his business to force a bill, known, the Hudson River, the Inland by any available means, through the Lakes, the Chesapeake, Delaware, and forms of legislation. Hence it will readily Narragansett Bays, and the whole interbe seen that a populous district, where nal navigation of the country, are thickpetitions will be numerously signed, ly studded with lights, supported by the though its coast be perfectly clear, is far munificent appropriations of Congress, more likely to secure a light than some and subject only to the casual and infrerocky promontory, full of danger and quent inspection of the Custom House terror to the mariner, if it chance to be Collectors. On the coast of Massachusetts unsettled. To this influence, and the from Newburyport to Plymouth, lights lack of proper checks upon it, is to be are placed at an average distance of six ascribed the fact that, while the safest miles apart, less than half the distance and most populous parts of our Atlantic at which each light should be visible. seaboard are thickly studded with lights, Look, on the other hand, at the coast of the more dangerous portions are quite Florida, the most dangerous sea track on neglected. It was one object of the law our Sea-Board. For hundreds of miles of 1837, to remedy this defect. It pro- not a light is to be seen, though every vided that before the building specified in wave hides some lurking danger. Bethe act of appropriation should be com- tween Key West and Cape Canaveral, menced, the site should be examined by the entire coast of three hundred miles, the Board of Commissioners, originally swept by a current, the Gulf Stream, composed, and very properly, of naval rapid and uncertain in its direction, one officers. Under the operation of this law, of the most dangerous portions of the during a single year, 31 of the Light- Atlantic Sea-Board, has but a single Houses for which appropriations were wretched floating light on Carysfoot made by the act of March 30, were de- Reef! And even this, from the ignorclared unnecessary, and the sum of ance which fixed its position, serves $168,000 was thus saved to the govern- little purpose except to lure vessels from ment. But even this provision was de. a chance of escape in darkness, to the fective. Though it gave to the qualified certainty of destruction. If the light-house Board the power of preventing the erec- system on this coast were what it should tion of needless Light-Houses, it still com- be, could a fleet of fifty “wreckers” be mitted the original selection of the site to sustained, and their thousand cormorants the superintendent of the district, who be enriched, by the proceeds of their was always the collector of customs ; semi-piratical profession? The salvage and seldom, if ever, possessed of the awarded to these men during a single combined knowledge of the engineer and year, has amounted to $170,000, a third the seaman, so essential to the proper of the sum required to sustain our whole discharge of this duty: and the building Light-House Establishment !| was of necessity adapted, not to the lo These facts, with many others which cality, but to the sum appropriated.* meet the eye in the most cursory exam

See the letter of the Fifth Auditor of the Treasury, appended to the Report of Lieut. Bache, House Doc. No. 24, A, 25th Congress, 3d Session.

| The Key West Correspondent of the Courier and Enquirer, in the number of that paper for the 22d of February, gives a list of twenty-three vessels wrecked at Key West, during the past year, on which the wreckers received a total salvage of $98,369. He also makes the following statement of the annual amount of salvage decreed at that place since 1831 :1831, $39,487. 1838,

$34,579.
1832,
46,555. 1839,

90,797.
1833,
38,128. 1840,

85,113.
1931,
32,012. 1841,

71,173.
1835,
87,249. 1842,

38,103.
1836,
174,132. 1843,

83,811.
1837,
107,495. 1844,

98,369. Here is an aggregate of $1,027,032, awarded to the wreckers of Key West since 1831,

ination, make it evident that our Light- in addition to his other multiplied duties, Houses are not always placed were they can scarcely command time to visit and are needed most; and this most serious properly inspect even once a year, the defect arises from the fact that their dis- intervals required by law, the ten or tribution is fixed by unqualified persons. twelve Light-Houses, hundreds of miles The evil has been felt for a long time, apart, which fall within his superintendand attempts have been made, as already ence; and the same thing, though perstated, to apply a remedy. The same haps to a less extent, is true of the same radical defect in the System, is felt in the officers at other ports. In point of fact, as construction of the buildings. When an is well known, the Light-Houses are rareappropriation for a Light-House is made, ly or never visited by the superintenda site is selected by a Collector of Cus- ents at all; and the only security for the toms in the district within which it falls. performance of the keepers' duty, lies in Not being a seaman, he is of course ig. the supposed surveillance of the Contracnorant of the precise spot from which tors, who, in turn, are said to be watched the light would afford the most assistance by the keepers. These are the checks to the mariner; and not being an en- provided by law for the proper regulation gineer, he knows little of the nature of the of these establishments; what provision foundation, or of the action of the sea has been made for the, at least supposable, and the currents in its neighborhood. contingency of collusion between keepers When the site has been chosen, the plan and contractors for their mutual benefit, of the building is furnished by the Fifth the Fifth Auditor of the Treasury DeAuditor of the Treasury, and the Super- partment does not inform us. How difintendent of the district advertises for ferently are these things managed in proposals to build in accordance with it. England and France! In that portion A mechanic is employed to examine the of the British System controlled by the work, and on his certificate that it is Trinity House, special agents are approperly done, it is accepted.* Under pointed for every Light-though, in some this system, as is inevitable, many build- cases, one has charge of several. Their ings have been very badly constructed. salaries vary according to their duties. One at Black Rock, Conn., built in 1829 at Sometimes, though rarely, they are Cusa cost of over $6,000, fell down in a very toms' Collectors, and frequently retired few days after it had been accepted. In masters in the maritime service. In 1835 it was rebuilt, at a cost of $8,748; many cases their whole time is occupied in the spring of 1836 it was saved from in the visitation, examination, and genbeing swept away, only by timely re eral supervision of the Houses placed pairs at an expense of $6,500, nearly its under their charge. We have before us original cost.f The same gross defects a statement of the number of visits made have been officially proved to exist in by each of these agents to each Lightthe construction of others.

House during the year 1833. By twenty The visitation and inspection of Light- of these agents nearly 500 visits of in. Houses is obviously of the utmost im- spection had been made during the year, portance to their proper management. It an average of twenty-five visits for each. is, in this country, as we have already The utmost exactness is required of the stated, committed to the Collectors of the keepers in the discharge of all their duCustoms, who are, ex officio, superin- ties, and the absence of one, for a single tendents of Light-Houses within their hour, from his post is severely punished. respective districts. No one acquainted The nineteenth article of the Instructions with the duties of the Collectorship, for the Light-Keepers of the Northern especially in the large seaports, where Lighl-Houses, declares that they “ have the Light-House supervision should be permission, on such occasions as pru. of the most exact and rigid character, dence may direct, to attend church, and can fail to see that they are scarcely able also to go from home to draw their sala. even nominally to perform this super- ries; but in such cases, only one keeper added duty. The Collector of New York, shall be absent from the Light-House at

as salvage. The aggregate expense of the whole Light House Establishment of the United States in any year never exceeded $613,376, the amount reached in 1839 • See the Fifth Auditor's Letter to Lieut. Bache, already referred to.

| House Doc., No. 24, 25th Cong., 3d Session, D. 2.

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one and the same time.” In this country $20,000, the government included in it is notorious that some of our principal their purchase a capital contrivance to Light-Houses are left for days in charge destroy the light which the filched patent of incompetent and irresponsible persons, was intended to create.

This was a not recognized by the regulations of the lens, consisting of one solid piece of Superintendent at Washington.* These glass, very thick and very bad. This irregularities must be replaced by an was stolen too, from the English light exact and thorough police, before our at the North Foreland. It was placed besystem can reach desired efficiency. fore the reflector; and the result, as de

The absence of scientific men from the scribed by Lieut. Drummond in his testidirection of the Light-House Establish- mony before the Committee of Parliament of this country, has the farther in- ment in 1834, was “entirely to destroy jurious effect, of retarding the adoption of the effect of the reflection; and, “in important improvements in the methods fact,” says he, it was absolutely putof illumination. None but men of sci. ting a shade before a very good light. ence can properly appreciate scientific In ordinary cases a window of a lantern discoveries; and if the control of the is of thick, clear plate-glass; but here, Light-House Establishments of Great instead of the plate-glass, they put a Britain and of France, had been as lens in front of each, which destroyed carefully withheld from men of this the parallelism of the beam of light from stamp as it is in this country, they and the reflector, and entirely injured its we might still have been burning tallow- effect. The reflector, it is true, did not candles on the tops of towers, as was the interfere with the action of the lens; but case in the Eddystone Light-House as from the thickness and badness of the recently as 1803. France has always glass, and other causes of an optical nataken the lead in improvements upon the ture, the effect of the lens was far inferior methods of lighting beacons, simply be- to that of the reflector when unobstructed cause she has always entrusted the mat- by the lens. The expense of each of ter to her most distinguished engineers these lenses was, 1 believe, about £40 and men of science. In 1784, her Tour or £50, and I think there were fifteen of de Corduan exhibited the Argand lamp, them in the Light-House. I believe it placed in the focus of the parabolic sil. had been in use about twenty or thirty vered mirror of the Chevalier de Borda; years at the North Foreland. By reand it was not until they had satisfied moving the lenses, the light was renderthemselves, by long trials and experi- ed much more brilliant; but these lenses ments, conducted « at considerable ex- when removed, were fit for nothing; they pense, and with unremitting trouble and were mischievous in the Light-House, solicitude,” of the expediency of so bold and useless when removed. An original an innovation, that the elder brethren of expense had been incurred to the amount the Trinity House, ventured to introduce of £750, to DESTROY A GOOD LIGHT.”[ it to the Light-Houses under their juris. And the United States Government, not diction. This was done in 1788, and in satisfied with incurring the expense of 1805 these reflectors were introduced in fitting up such an apparatus, paid twenty the Scottish lights, by Robert Stevenson, thousand dollars for the patent! And in the engineer to the Board of Commission. 1840, one of these very light destroying ers. In 1808, the Light-House at Holy- contrivances was used in a Light-House head was erected, and the next year was on Long Island. This fact alone speaks supplied with the apparatus of De Borda, trumpet-tongued in proclamation of the to the great benefit of navigation in the utter lack of all scientific knowledge, Irish channel. In 1812, the Government which has pervaded the superintendence of the United States purchased, at the of our Light-House Establishment. round price of $20,000, the patent for The parabolic reflectors, thus patented this method of illumination—the patent by our government more than a quarter for a method which had been twenty- of a century after their use in France, eight years in use in France, and more continued to be for a long time, and inthan twenty in England! Nor was this deed are still, in general use in Great all. Not content with patenting an old Britain and in this country. They were invention, and huying the patent for invented, as already stated, by De Borda,

* See letter of Capt. M. C. Perry, Senate Doc. 619, 26th Congress, 1st Session. † Minutes of Evidence taken before Committee, Report of 1834, 2997-3003.

and first used in the Tour de Corduan. which was found to absorb more light They are made of thin sheet copper, than it refracted ; and though before 1750 plated over with a thin film of silver. Buffon the naturalist had suggested a În their manufacture, as conducted in method of grinding away a part of the this country, the plater rolls out a disc useless surface, this had been found of copper, coated with a lamina of silver. quite impracticable, and the plan of This disc of metal, varying in diameter using a lens had gradually been abanaccording to the size of the reflector, is doned. handed over to a coppersmith, who ham. In 1811, Dr. Brewster invented a mers it to the requisite concavity, the method of building lenses of any mag: curvature being ascertained by the use nitude required, of separate pieces ; and of a wooden mould. Next, the silver- in 1812, he minutely described this smith burnishes the silver surface, in the method, in his “ Treatise on Burning usual way; and, when this is done, the Instruments, containing the method of reflector is complete. An argand burner building large Polyzonal Lenses.” This is then placed in the focus, and supplied important invention, however, excited with oil from a fountain-lamp placed little notice in England, until it had first behind. The form of the reflector is sup- been applied, with the most decided posed to be a parabola. During the success, in France. In 1822, M. Fresnel, animated discussion of 1833 and ’4, con a distinguished member of the French cerning the Light-House System of Great Light-House Commission, published a Britain, an able writer in the Edinburgh

Memoire sur un Noveau Système Review, supposed to have been Sir d'Eclairage des Phares,” in which he David Brewster, alludes to imperfections earnestly recommended the substitution rendered unavoidable in these reflectors, of lenses for reflectors in the Light-Houses by difficulties of mechanical execution; of France. He does not claim originality and his objections,* as every scientific in this idea of the superiority of lenses, person must see, are well founded, and for he says distinctly, that “this appliprove the inefficiency of reflectors in cation of lenses to the illumination of cases where the best possible lights are re Light-Houses cannot be a new idea, for quired. They have been found, however, it readily suggests itself to the mind; extremely useful in ordinary cases, and and there exists in reality a lens Lightindeed, until a more perfect apparatus House in England." This was the lower was invented, they were used in all the Light-House in the Isle of Portland, fitted Light-Houses of France and Great Britain up with lenses in 1789; owing to deas well as in those of this country. But fective construction, however, and a for many years it has been felt that, in general ignorance of the best methods principle, and according to all optical of applying them, the experiment as laws, lenses would be far better concen- already stated, had not proved successtrators of light than reflectors. The law ful. In consequence of Fresnel's recomquoted by the Edinburgh Reviewer, from mendation, the Light-House at Corduan Sir Isaac Newton, that · every inequality was fitted up with the polyzonal lens ; in a reflecting surface makes the rays and the result was so satisfactory, that stray five or six times more out of their the French Government, in 1825, adoptdue course, than the like inequalities in ed his improvements throughout the a refracting one, announces, indeed, the Light-House Establishment of the kingdecided superiority, of the dioptric to the dom. catoptric principle in its application to The success of this experiment induced lighthouse as well as to telescopic illu- Mr. Robert Stevenson, Engineer to the mination. And, as early as the year Scottish Light-House Board, to go to 1780, attempts had been made to intro. France in 1825. He saw M. Fresnel and duce a polyzonal lens in France, by the bought one of his polyzonal lenses; but Abbe Rocheu, and in Scotland by Messrs. no steps were immediately taken to test Cooksen of Newcastle-upon-Tyne. Dif- its efficacy by experiment. Sir David ficulties of construction, however, pre- Brewster, in the early part of 1826, advented the success of the experiment, dressed to the Board a memorial on the though it was clearly established in theory.subject; and in 1827, corresponded with The great difficulty to be encountered, the Trinity House and the Irish Board in arose from the thickness of the glass, reference to the substitution of polyzonal

Edinburgh Review, Vol. 57, p. 180.

sons.

lenses for reflectors. It was not, how- Committee, Lieut. Drummond also stated, ever, until 1831 that any efficient mea- that "the light given by the lens was sures were taken to test the superiority found by the experiments at the Trinity of the new invention. In February of House in London, to be equal to that of that year the Commissioners appointed a nine reflectors.” He also spoke of an committee “ for the purpose of conduct- additional apparatus, to which we have ing experiments on the comparative me not yet alluded. It is simply a combirits of lenses and reflectors.” From a nation of reflectors placed above and bevariety of causes these experiments were low the lens, to collect the light that not made until February, 1833.* They would otherwise pass beyond instead of took place upon Gulan Hill, on the Coast through them. With this, he considered of Haddingtonshire: the lenses and re a single lens fully equal to ten reflectors. flectors being placed in temporary cabins In consequence of these representaerected for the purpose, about one hund- tions, the Light-House on the island of red yards apart, were obsevred from Inskerth, in the Frith of Forth, a few Calton Hill, twelve miles distant, by Sir miles from Leith, was fitted up, in 1835, David Brewster and other scientific per- with a lenticular apparatus; and the in

Mr. Stevenson, the Reporter of creased brilliancy of the new light was the Committee, in his account of these so apparent, that a number of others experiments, says:

bave since been established in the king

dom and by the government in the colo“ The result of the experiments, in the nies. The French light at Barfleur is judgment of the reporter, was that the lens probably the most splendid in any Lightlight had a more brilliant appearance than House in the world; and exemplifies the reflected light till the number of re- better than any other the real efficiency flectors were increased to about seven or of the lenticular method of illumination. eight, when both lights seemed equal to the It is lighted, like all others of this kind, naked eye; but when seen through the by a single lamp, having four concentric medium of a telescope, the lens light ap: wicks, the largest being three and onepeared to more advantage in point of brilliancy or intensity, while the body of half inches in diameter. These wicks the reflected light appeared larger to the are raised on cylinders, separated so that naked eye."

the air can pass between them, and pro

duce a flame six inches high. This lamp, In summing up his report on the ex- being placed in the centre, is surrounded periments of the third night, Mr. Steven- by sixteen lenses, in oblong frames, 34 son says :-“ It also appears from the inches high and 14} wide, standing side experiments with the lens and reflectors, by side on one ring and steadied by anthat from seven to NINE of the reflectors other laid on top and screwed fast to the nou in use at the Northern Lights pro- frames, thus forming a sixteen sided duce a light equal to that of the lens.”* prism, of about six feet in diameter and

These experiments seem very clearly thirty-four inches high. Each lens is to establish the fact that a single poly. composed of several separate pieces of zonal lens with one Argand burner of glass, put together in the manner inventfour concentric wicks, gave a light equaled by Sir David Brewster and afterwards to that of nine reflectors, each carrying by Fresnel and Arago; the center piece a single Argand burner. Sir David Brew- being a perfect plano-convex lens, having ster, in a communication addressed to the Hat side towards the light, and the the committee, expressed in very nearly others being portions of circular prisms the terms we have used, his judgment concentric with the lens. The same efof the result, and quoted a similar con. fect, of course, is produced as from a lens clusion reached by the Academy of Sci- the entire size of all these pieces taken ences of St Petersburgh more than tive together, except that it is greatly inyears before, as well as an opinion to creased by the inferior thickness of the the same effect, expressed by Sir John central glass. The backs of all these Herschell in his Discourse on Natural pieces being in the same plane, a vertical Philosophy. In his examination by the cross-section through the centre would

The official account of these experiments, which were made on the nights of the 12th, 13th, and 14th of February, 1833, may be found in the Appendix to the Report of the Select Committee of Parliament on Light-Houses, in 1834 ; No. 130, page 127 of the Report.

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