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and considerable disbursement of the public money in their immediate vicinity. Petitions, of course, and a sense of his responsibility at the ballot-boxes, impress him with a similar conviction and it becomes his business to force a bill, by any available means, through the forms of legislation. Hence it will readily be seen that a populous district, where petitions will be numerously signed, though its coast be perfectly clear, is far more likely to secure a light than some rocky promontory, full of danger and terror to the mariner, if it chance to be unsettled. To this influence, and the lack of proper checks upon it, is to be ascribed the fact that, while the safest and most populous parts of our Atlantic seaboard are thickly studded with lights, the more dangerous portions are quite neglected. It was one object of the law of 1837, to remedy this defect. It provided that before the building specified in the act of appropriation should be commenced, the site should be examined by the Board of Commissioners, originally composed, and very properly, of naval officers. Under the operation of this law, during a single year, 31 of the LightHouses for which appropriations were made by the act of March 30, were declared unnecessary, and the sum of $168,000 was thus saved to the govern

ment.

But even this provision was defective. Though it gave to the qualified Board the power of preventing the erection of needless Light-Houses, it still committed the original selection of the site to the superintendent of the district, who was always the collector of customs;and seldom, if ever, possessed of the combined knowledge of the engineer and the seaman, so essential to the proper discharge of this duty: and the building was of necessity adapted, not to the locality, but to the sum appropriated.*

The effect of this very defective arrangement, may be seen by a glance at a chart on which the Light-Houses of the sea board are marked. The New England coast, comparatively safe and wellknown, the Hudson River, the Inland Lakes, the Chesapeake, Delaware, and Narragansett Bays, and the whole internal navigation of the country, are thickly studded with lights, supported by the munificent appropriations of Congress, and subject only to the casual and infrequent inspection of the Custom House Collectors. On the coast of Massachusetts from Newburyport to Plymouth, lights are placed at an average distance of six miles apart, less than half the distance at which each light should be visible. Look, on the other hand, at the coast of Florida, the most dangerous sea track on our Sea-Board. For hundreds of miles not a light is to be seen, though every wave hides some lurking danger. tween Key West and Cape Canaveral, the entire coast of three hundred miles, swept by a current, the Gulf Stream, rapid and uncertain in its direction, one of the most dangerous portions of the Atlantic Sea-Board, has but a single wretched floating light on Carysfoot Reef! And even this, from the ignorance which fixed its position, serves little purpose except to lure vessels from a chance of escape in darkness, to the certainty of destruction. If the light-house system on this coast were what it should be, could a fleet of fifty "wreckers" be sustained, and their thousand cormorants be enriched, by the proceeds of their semi-piratical profession? The salvage awarded to these men during a single year, has amounted to $170,000, a third of the sum required to sustain our whole Light-House Establishment !†

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These facts, with many others which 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:—

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

ination, make it evident that our LightHouses are not always placed were they are needed most; and this most serious defect arises from the fact that their distribution is fixed by unqualified persons. The evil has been felt for a long time, and attempts have been made, as already stated, to apply a remedy. The same radical defect in the System, is felt in the construction of the buildings. When an appropriation for a Light-House is made, a site is selected by a Collector of Customs in the district within which it falls. Not being a seaman, he is of course ignorant of the precise spot from which the light would afford the most assistance to the mariner; and not being an engineer, he knows little of the nature of the foundation, or of the action of the sea and the currents in its neighborhood. When the site has been chosen, the plan of the building is furnished by the Fifth Auditor of the Treasury, and the Superintendent of the district advertises for proposals to build in accordance with it. A mechanic is employed to examine the work, and on his certificate that it is properly done, it is accepted. Under this system, as is inevitable, many buildings have been very badly constructed. One at Black Rock, Conn., built in 1829 at a cost of over $6,000, fell down in a very few days after it had been accepted. In 1835 it was rebuilt, at a cost of $8,748; in the spring of 1836 it was saved from being swept away, only by timely repairs at an expense of $6,500, nearly its original cost. The same gross defects have been officially proved to exist in the construction of others.

The visitation and inspection of LightHouses is obviously of the utmost importance to their proper management. It is, in this country, as we have already stated, committed to the Collectors of the Customs, who are, ex officio, superintendents of Light-Houses within their respective districts. No one acquainted with the duties of the Collectorship, especially in the large seaports, where the Light-House supervision should be of the most exact and rigid character, can fail to see that they are scarcely able even nominally to perform this superadded duty. The Collector of New York,

in addition to his other multiplied duties, can scarcely command time to visit and properly inspect even once a year, the intervals required by law, the ten or twelve Light-Houses, hundreds of miles apart, which fall within his superintendence; and the same thing, though perhaps to a less extent, is true of the same officers at other ports. In point of fact, as is well known, the Light-Houses are rarely or never visited by the superintendents at all; and the only security for the performance of the keepers' duty, lies in the supposed surveillance of the Contractors, who, in turn, are said to be watched by the keepers. These are the checks provided by law for the proper regulation of these establishments; what provision has been made for the, at least supposable, contingency of collusion between keepers and contractors for their mutual benefit, the Fifth Auditor of the Treasury Department does not inform us. ferently are these things managed in England and France! In that portion of the British System controlled by the Trinity House, special agents are appointed for every Light-though, in some cases, one has charge of several. Their salaries vary according to their duties. Sometimes, though rarely, they are Customs' Collectors, and frequently retired masters in the maritime service. many cases their whole time is occupied in the visitation, examination, and general supervision of the Houses placed under their charge. We have before us

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a statement of the number of visits made by each of these agents to each LightHouse during the year 1833. By twenty of these agents nearly 500 visits of inspection had been made during the year, an average of twenty-five visits for each. The utmost exactness is required of the keepers in the discharge of all their duties, and the absence of one, for a single hour, from his post is severely punished. The nineteenth article of the Instructions for the Light-Keepers of the Northern Light-Houses, declares that they "have permission, on such occasions as pru dence may direct, to attend church, and also to go from home to draw their salaries; but in such cases, only one keeper 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.

one and the same time." In this country it is notorious that some of our principal Light-Houses are left for days in charge of incompetent and irresponsible persons, not recognized by the regulations of the Superintendent at Washington. These irregularities must be replaced by an exact and thorough police, before our system can reach desired efficiency.

The absence of scientific men from the direction of the Light-House Establishment of this country, has the farther injurious effect, of retarding the adoption of important improvements in the methods of illumination. None but men of science can properly appreciate scientific discoveries; and if the control of the Light-House Establishments of Great Britain and of France, had been as carefully withheld from men of this stamp as it is in this country, they and we might still have been burning tallow candles on the tops of towers, as was the case in the Eddystone Light-House as recently as 1803. France has always taken the lead in improvements upon the methods of lighting beacons, simply because she has always entrusted the matter to her most distinguished engineers and men of science. In 1784, her Tour de Corduan exhibited the Argand lamp, placed in the focus of the parabolic silvered mirror of the Chevalier de Borda; and it was not until they had satisfied themselves, by long trials and experiments, conducted at considerable expense, and with unremitting trouble and solicitude," of the expediency of so bold an innovation, that the elder brethren of the Trinity House, ventured to introduce it to the Light-Houses under their jurisdiction. This was done in 1788, and in 1805 these reflectors were introduced in the Scottish lights, by Robert Stevenson, the engineer to the Board of Commissioners. In 1808, the Light-House at Holyhead was erected, and the next year was supplied with the apparatus of De Borda, to the great benefit of navigation in the Irish channel. In 1812, the Government of the United States purchased, at the round price of $20,000, the patent for this method of illumination-the patent for a method which had been twentyeight years in use in France, and more than twenty in England! Nor was this all. Not content with patenting an old invention, and buying the patent for

$20,000, the government included in their purchase a capital contrivance to destroy the light which the filched patent was intended to create. This was a lens, consisting of one solid piece of glass, very thick and very bad. This was stolen too, from the English light at the North Foreland. It was placed before the reflector; and the result, as described by Lieut. Drummond in his testimony before the Committee of Parliament in 1834, was "entirely to destroy the effect of the reflection" and, "in fact," says he, "it was absolutely putting a shade before a very good light. In ordinary cases a window of a lantern is of thick, clear plate-glass; but here, instead of the plate-glass, they put a lens in front of each, which destroyed the parallelism of the beam of light from the reflector, and entirely injured its effect. The reflector, it is true, did not interfere with the action of the lens; but from the thickness and badness of the glass, and other causes of an optical nature, the effect of the lens was far inferior to that of the reflector when unobstructed by the lens. The expense of each of these lenses was, I believe, about £40 or £50, and I think there were fifteen of them in the Light-House. I believe it had been in use about twenty or thirty years at the North Foreland. By removing the lenses, the light was rendered much more brilliant; but these lenses when removed, were fit for nothing; they were mischievous in the Light-House, and useless when removed. An original expense had been incurred to the amount of £750, to DESTROY A GOOD LIGHT.”† And the United States Government, not satisfied with incurring the expense of fitting up such an apparatus, paid twenty thousand dollars for the patent! And in 1840, one of these very light destroying contrivances was used in a Light-House on Long Island. This fact alone speaks trumpet-tongued in proclamation of the utter lack of all scientific knowledge, which has pervaded the superintendence of our Light-House Establishment.

The parabolic reflectors, thus patented by our government more than a quarter of a century after their use in France, continued to be for a long time, and indeed are still, in general use in Great Britain and in this country. They were 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. They are made of thin sheet copper, plated over with a thin film of silver. In their manufacture, as conducted in this country, the plater rolls out a disc of copper, coated with a lamina of silver. This disc of metal, varying in diameter according to the size of the reflector, is handed over to a coppersmith, who hammers it to the requisite concavity, the curvature being ascertained by the use of a wooden mould. Next, the silversmith burnishes the silver surface, in the usual way; and, when this is done, the reflector is complete. An argand burner is then placed in the focus, and supplied with oil from a fountain-lamp placed behind. The form of the reflector is supposed to be a parabola. During the animated discussion of 1833 and '4, concerning the Light-House System of Great Britain, an able writer in the Edinburgh Review, supposed to have been Sir David Brewster, alludes to imperfections rendered unavoidable in these reflectors, by difficulties of mechanical execution; and his objections, as every scientific person must see, are well founded, and prove the inefficiency of reflectors in cases where the best possible lights are required. They have been found, however, extremely useful in ordinary cases, and indeed, until a more perfect apparatus was invented, they were used in all the Light-Houses of France and Great Britain as well as in those of this country. But for many years it has been felt that, in principle, and according to all optical laws, lenses would be far better concentrators of light than reflectors. The law quoted by the Edinburgh Reviewer, from Sir Isaac Newton, that every inequality in a reflecting surface makes the rays stray five or six times more out of their due course, than the like inequalities in a refracting one,' announces, indeed, the decided superiority, of the dioptric to the catoptric principle in its application to lighthouse as well as to telescopic illumination. And, as early as the year 1780, attempts had been made to introduce a polyzonal lens in France, by the Abbe Rocheu, and in Scotland by Messrs. Cooksen of Newcastle-upon-Tyne. Difficulties of construction, however, prevented the success of the experiment, though it was clearly established in theory. The great difficulty to be encountered, arose from the thickness of the glass,

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which was found to absorb more light than it refracted; and though before 1750 Buffon the naturalist had suggested a method of grinding away a part of the useless surface, this had been found quite impracticable, and the plan of using a lens had gradually been abandoned.

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In 1811, Dr. Brewster invented a method of building lenses of any magnitude required, of separate pieces; and in 1812, he minutely described this method, in his Treatise on Burning Instruments, containing the method of building large Polyzonal Lenses." This important invention, however, excited little notice in England, until it had first been applied, with the most decided success, in France. In 1822, M. Fresnel, a distinguished member of the French Light-House Commission, published a Memoire sur un Noveau Système d'Eclairage des Phares," in which he earnestly recommended the substitution of lenses for reflectors in the Light-Houses of France. He does not claim originality in this idea of the superiority of lenses, for he says distinctly, that "this application of lenses to the illumination of Light-Houses cannot be a new idea, for it readily suggests itself to the mind; and there exists in reality a lens LightHouse in England." This was the lower Light-House in the Isle of Portland, fitted up with lenses in 1789; owing to defective construction, however, and a general ignorance of the best methods of applying them, the experiment as already stated, had not proved successful. In consequence of Fresnel's recommendation, the Light-House at Corduan was fitted up with the polyzonal lens; and the result was so satisfactory, that the French Government, in 1825, adopted his improvements throughout the Light-House Establishment of the kingdom.

The success of this experiment induced Mr. Robert Stevenson, Engineer to the Scottish Light-House Board, to go to France in 1825. He saw M. Fresnel and bought one of his polyzonal lenses; but no steps were immediately taken to test its efficacy by experiment. Sir David Brewster, in the early part of 1826, addressed to the Board a memorial on the subject; and in 1827, corresponded with the Trinity House and the Irish Board in reference to the substitution of polyzonal

Edinburgh Review, Vol. 57, p. 180.

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lenses for reflectors. It was not, however, until 1831 that any efficient measures were taken to test the superiority of the new invention. In February of that year the Commissioners appointed a committee for the purpose of conducting experiments on the comparative merits of lenses and reflectors." From a variety of causes these experiments were not made until February, 1833. They took place upon Gulan Hill, on the Coast of Haddingtonshire: the lenses and reflectors being placed in temporary cabins erected for the purpose, about one hundred yards apart, were obsevred from Calton Hill, twelve miles distant, by Sir David Brewster and other scientific persons. Mr. Stevenson, the Reporter of the Committee, in his account of these experiments, says:

“The result of the experiments, in the judgment of the reporter, was that the lens light had a more brilliant appearance than the reflected light till the number of reflectors were increased to about seven or eight, when both lights seemed equal to the naked eye; but when seen through the medium of a telescope, the lens light ap peared to more advantage in point of brilliancy or intensity, while the body of the reflected light appeared larger to the naked eye."

In summing up his report on the experiments of the third night, Mr. Stevenson says: "It also appears from the experiments with the lens and reflectors, that from SEVEN to NINE of the reflectors now in use at the Northern Lights produce a light equal to that of the lens.”

These experiments seem very clearly to establish the fact that a single polyzonal lens with one Argand burner of four concentric wicks, gave a light equal to that of nine reflectors, each carrying a single Argand burner. Sir David Brewster, in a communication addressed to the committee, expressed in very nearly the terms we have used, his judgment of the result, and quoted a similar conclusion reached by the Academy of Sciences of St Petersburgh more than five years before, as well as an opinion to the same effect, expressed by Sir John Herschell in his Discourse on Natural Philosophy. In his examination by the

Committee, Lieut. Drummond also stated, that "the light given by the lens was found by the experiments at the Trinity House in London, to be equal to that of nine reflectors." He also spoke of an additional apparatus, to which we have not yet alluded. It is simply a combination of reflectors placed above and below the lens, to collect the light that would otherwise pass beyond instead of through them. With this, he considered a single lens fully equal to TEN reflectors.

In consequence of these representations, the Light-House on the Island of Inskerth, in the Frith of Forth, a few miles from Leith, was fitted up, in 1835, with a lenticular apparatus; and the increased brilliancy of the new light was so apparent, that a number of others have since been established in the kingdom and by the government in the colonies. The French light at Barfleur is probably the most splendid in any LightHouse in the world; and exemplifies better than any other the real efficiency of the lenticular method of illumination.

It is lighted, like all others of this kind, wicks, the largest being three and oneby a single lamp, having four concentric half inches in diameter. These wicks are raised on cylinders, separated so that the air can pass between them, and produce a flame six inches high. This lamp, being placed in the centre, is surrounded by sixteen lenses, in oblong frames, 34 inches high and 14 wide, standing side by side on one ring and steadied by another laid on top and screwed fast to the frames, thus forming a sixteen sided prism, of about six feet in diameter and thirty-four inches high. Each lens is composed of several separate pieces of glass, put together in the manner invented by Sir David Brewster and afterwards by Fresnel and Arago; the center piece being a perfect plano-convex lens, having the flat side towards the light, and the others being portions of circular prisms concentric with the lens. The same effect, of course, is produced as from a lens the entire size of all these pieces taken together, except that it is greatly increased by the inferior thickness of the central glass. The backs of all these pieces being in the same plane, a vertical 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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