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ments, which were ballasted to make it firm. in May, 1870, and the light was first exhibited Thus a protected pond was formed for the from the finished structure in June, 1874; but coffer-dam, designed by General W. F. Ray- the available working time spent on this lightnolds, of the United States Engineers, and a house was but about twenty months. This towlanding wharf was afforded for material, as er, which cost, including the steamer and appliwell as for the reception of quarters for the ances of all kinds, about $375,000, is our best men, all twelve feet above water, and out of specimen of monolithic stone masonry. It was reach of ordinary waves. The cotfer-dam was built by General O. M. Poe, of the United States thirty-six feet across, and cylindrical in form. Engineers, who was General Sherman's chief It was made of jointed staves fourteen feet engineer in his march to the sea. Its strength long, four inches thick, and six inches wide, has been thoroughly tested by the ice push held in place by three iron hoops, like a tub, already. When the keepers returned to the and braced and stayed inside against a center tower on May 15, 1874, they found the ice post, the axis of which coincided with the axis piled against it to a height of thirty feet, which

is seven feet higher than the doorway, and they could not effect an entrance to the tower until they had cut through the iceberg, of which this lighthouse formed the core. The cut shows this lighthouse surrounded by an ice-floe.

The board is now building a stone tower in Lake Superior, on Stannard's Rock, twentyeight miles from shore, for which the steamer and the plant used in erecting the light on Spectacle Reef are being used. It will be, when finished, 1014 feet in height, will cost about $300,000, and will show a light of the second order.

Tillamook (Oregon) lighthouse is placed on an isolated basalt rock high out of water, about one mile from the mainland, in fifteen fathoms of water, and about twenty miles south of the mouth of Columbia River. It is divided above low water into two unequal parts by a wide fissure, with vertical sides running east and west, standing one hundred feet above the sea, with a crest capable of such reduction as to accommodate a structure not larger than fifty feet square. A landing could with difficulty be made on the side next the shore during a smooth sea. The rugged character of the headland, the tendency of the sea face to landslides, and the great distance from Astoria, the nearest supply-point, made the execution of the work a task of labor, difficulty, danger, and expense. The drowning of the foreman on the landing of the first working-party tended to

confirm the prejudices of the local public of the cylindrical coffer. It was built at the against the enterprise, and to increase the dif. surface of the water, and suspended exactly ficulty of obtaining the services of skilled over the site of the tower. A loosely twisted workinen. On October 21, 1879, however, inch and a half rope of oakum was tucked to four workmen, with hammers, drills, bolts, the lower end of the staves, and then the cylin. provisions, fuel, a stove, and some canvas to der was lowered to the bed-rock, which had protect them and their supplies from the such irregularities on its surface that some of weather, were landed, and, a few days later, them were three feet high. All these were com five more men and a small derrick were got to pensated by driving the jointed staves home the rock, from which time the commencement with a heavy top-maul, the vakum rope serving of the work may be dated. For the first nine as calking; and this was made approxima- days after reaching the rock, the nine quarrytively water-tight by an ingenious arrangement men had no shelter from the rain and spray, of a loosely twisted four-inch hay-rope and except that of the canvas lashed to ringbolts. a canvas flap, which was attached in part to But during this time they cut a shallow niche the outside of the lower edge of the cylinder, in the north and east sides, in which they set that lay in part flat on the rock, and which up a strong timber shanty, which they bolted was forced into the angle by the outside press- to the rock, covered with canvas, and secured ure when the pumps commenced lowering the to ringbolts. From this they secured safety, water in the dam. The work was commenced but got little comfort. After setting up the

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SPECTACLE REEF LIGHTHOUSE, LAKE HURON.

main derrick and cutting a pathway up the bar at the mouth of the Columbia River to go face of the rock, they opened a bench around to their assistance ; when, after sixteen days, it by suspending the workmen on staging sup- communication was reopened, the party was ported by bolts let into the rock's crest. The found to be safe, but much in want of fresh bench once formed, the reduction was pushed provisions. These were supplied by an endless to the center. The outer surface of the rock line running between the mast of the supplywas easily removed with moderate charges of vessel and a ringbolt driven into the top of the black powder, but the nucleus was hard and rock, in water-tight casks suspended by slings firin, and giant-powder was necessary to open from a traveler, which was made to move along the mass, when large charges of black powder the line. acted satisfactorily. The working party, in In May the top of the rock was leveled, and spite of their rude, uncomfortable quarters, a foundation made about eighty-eight feet worked diligently through the winter with above the sea, and, on the 31st, three masons, good results. But the work was much delayed four derricks, a small engine, and the appliby spells of weather so bad that little could be ances for laying the masonry, were landed. done. The coast was visited by a tornado in The stone, a tine-grained, compact basalt, quarJanuary, which caused the waves, reflected ried near Portland, and cut to dimensions by from the rock, to be carried by the wind over contract, was delivered at Astoria and shipped its crest, so that for many days continuously to the rock on the tender. The first cargo was the receding floods poured over the eastern landed on June 17th ; on the 22d the cornerslope, making work impossible. On one such stone was laid, and then the rest of the mateday this cataract carried away the supply. rial was shipped to the rock as the weather house, and even endangered the quarters of permitted. the working-party. For more than two weeks The building is a square, one-story keeper's at this time it was impossible for the ste:im- dwelling, with a rectangular extension for the tender which supplied their wants to cross the duplicate siren fog-signal apparatus. From the

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center of the keeper's dwelling rises the tower, earlier, it probably would have saved the English which is crowned by a gallery and a lantern iron bark Lupata, of 1,039 tons burden, which containing a first-order lens apparatus. The was dashed to pieces on the main shore, not a material used is stone, cut to dimensions on mile from the lighthouse, with a loss of the the shore, for the outer walls, and brick, iron, vessel, its freight, and every one of the twenty and wood for the interior. The light is forty- persons on board. The bark came so near the eight feet above the base of the tower and one rock that the creaking of the blocks and the hundred and thirty-six feet above mean sea

of officers giving orders were dislevel, and it was shown for the first time on Feb. tinctly heard, but the night was so dark that ruary 1, 1881. If it had been finished a month nothing could be seen except her lights. The

local foreman had a bonfire built on the rock if not reaching, the paraboloid in form, and as soon as possible, but the vessel was lost were heavily silvered and properly placed. probably before the signal could be seen. It The heavy lantern frames were replaced by was on this night that the working-party lost lighter ones, the small panes of glass by larger their supply-house, and came so near losing ones, and the ventilation of the towers was so their quarters, if not their lives.

largely improved that obscuration by smoke The illuminating apparatus used by the light- was no longer unpreventable. The system, house establishment varied with tlie dates of largely improved, was retained, but its adminits use.

The beacon on Point Allerton, Mas- istration was good only where it had faithful, sachusetts, was illumined in 1673 by “fier intelligent, and honest administrators. Finally, balls of pitch and ocum,” burned in open the retlectors were so well made and so well braziers. The lighthouse on Little Brewster placed that, in certain instances, it is now a Islard, Boston IIarbor, erected in 1715-'16, question whether a better light was possible was first lighted by tallow candles. Then fol- than was then iurnished. Some of the old relowed the spider lamp, burned in the lantern flectors then used appear from recent examas it inight have been in a window. In 1812 ination to have an enormous candle power. the Government bought of Mr. Winslow Lewis, But a poor light was the rule, and a good light for $20,000, the patent for his “magnifying the exception. War was made on the system and refiecting lantern.” This is described as of reflectors, and, when the lighthouse estabconsisting of a lamp, il reflector, and what was lishment was turned over to the Lighthouse called the magnifier. The reflector was of a Board in 1852, the reflectors were replaced by thin sheet of copper, commonly segments of a the Fresnel lenticular apparatus, found so sucsphere, plated over with a slight film of silver, cessful in France, and more or less throughout though the copper was so thin that its com the world. The adoption in this country of pression between the arms of its iron supports the lenticular apparatus made it possible for a materially altered its forin, and its silvered con- light-keeper of average capacity to keep a good cave surface had much the grain and luster of light, and impossible for bim to keep a bad tin ware, and would reflect no distinct image. one, except by violation of plain rules and The patentee, in 1812, made no pretension to a avoidance of routine duties. Besides this, the knowledge of optics as now understood, and saving in oil effected by use of the lenses over his reflectors came about as near to a true reflectors was so great that the expense of exparaboloid as did a barber's basin. The lamp, changing the one for the other was saved in a roughly constructed on the principle of Ar- few years, although the first cost of the lenses gand's fountain-lamp, burning from thirty to was quite large. forty gallons of oil per year, had a three-quarter It was shown, in a report made to Congress inch burner, and was attached to a circular iron in 1858, that the mean average cost of each frame in front of the reflector. Before the lighthouse, for the five and a quarter years lamp was a so-called lens, of bottle-green glass, preceding the organization of the Lighthouse shaped like the bull's-eye let into a ship's deck, Board, was $1,302, with oil at an average of from two and a half to four inches thick $1.13 per gallon, while, for the same period through the axis and nine inches in diameter, after the board took charge, it was but $1,286, which was supposed to have some magnifying with oil at $1.62 per gallon. Thus it appeared power. This apparatus was inclosed in a mas that under the board the arerage cost of mainsive wrought-iron lantern, glazed with panes taining cach light was about $10 per year less ten by twelve inchies in size. The effect of the than under the previous management, although whole was characterized by one of the report- oil was abont fifty cents per gallon more ; and ing inspectors as making a bad light worse. it was broadly claimed by the board, and the But its main merit seems to have been that of claim does not appear to have been dispated, economy, as the patentee, who liad fitted thirty- that by the change it furnished ander the new four lighthouses with his apparatus, contracted system, " at least four times as much light for in 1816 to maintain the lights on receiving one the benefit of the navigator as the best system half the oil previously consumed, and again, in of reflector lights which has been devised, and 1821, for one third of the old allowanco. at the same time at a consumption of not more

This apparatus is spoken of more respect- than one fourth of the quantity of oil, required fully in a report to the House of Representa- for the best system of reflector lights." tives in 1812, made by its committee on com A full description is given in Appletons' merce, from which it appears that “the im Cyclopædia” of the reflectors, under the head provement in the character of the light and LIGHTHOUSES, and of the lenticular apparatus the economy in saving oil were subjects of high under the name of Augustin FRESNEL, its incommendation by the Government.” It also ventor. appears that the use of the magnifying bull's-eye The illuminant of the lighthouse establishwas gradually abandoned, so that but few re ment has been changed whenever a better one mained in 18:38, and the last one was removed has been found. The "fier-balls of pitch and in 1810. The adıninistration of the system ocum,"used in the open brazier at Point Allerwas largely improved. The reflectors were ton in 1673, were succeeded by tallow candles made on true optical principles, approximating, at Little Brewster Island in 1710, whiclı gare

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way to fish-oil, burned in spider-lamps, with Oil for the year is usually purchased by consolid wicks, suspended by iron chains from the tract in the autumn, after advertisements for dome of Sandy Hook lighthouse as late as proposals, and is made deliverable in large lots 1760; and this was in turn succeeded in 1812 at different times and places, to suit the conby sperm-oil, burned in a sort of argand lamp venience of the establishment. When delivered, in Winslow's “patent magnifying and reflect- it is subjected to careful and exact test, to ascering lanterns"; and this illuminant was contin- tain its purity; and its light-giving power, in ued until the beginning of the latter half of the lighthouse lamps, is ascertained by photomepresent century, when the reflector system, tric measurement. The best oil of commerce is much as it was improred, was itself superseded not always the best for lighthouse lamps, and by the Fresnel lenticular apparatus, now in use. the dealers have much difficulty in meeting the

When the Lighthouse Board came into precise wants of the establishment; hence it is power, one of the first subjects which received not unusual that some oil is rejected. Taking its best attention was that of obtaining a new the oil purchased in open market, to meet sudilluminant of less cost than sperm-oil. The den demands, which it is cheaper to meet by yearly diminution of the whale catch and the purchase than by transportation, together with increased use of sperm-oil as a lubricant made that purchased by contract, the establishment it more and more expensive. The board, there. bought on an average about 100,000 gallons of fore, called in the aid of such scientists as Pro- oil yearly. The highest price it has paid for fessors Morfit and Alexander, of the University sperm-oil was $2.43 $ per gallon, the lowest of Maryland. Their analyses, quantitative and $1.09; the highest that it has paid for lard-oil qualitative, chemical, photometric, etc., of was $2.27, and lowest 48} cents per gallon. sperin, whale, shark, fish, seal, colza, olive, lard, and mineral oils, of various grades and The lard-oil used by the lighthouse establishment

from 1867 to 1880, both inclusive. combinations, were published by the board in 1855, and these are still regarded by the trades as high authority on those subjects. It was found from these examinations that

75,000 $1.294 $90,950 00 colza, the oil expressed from the seed of several

53,000 1.270

69,950 00 plants, but especially from that of the wild cab

1.4913

89,425 0:5 80,000

14), 140 00 bage (brassica oleracea) was largely used in

91,000

113,197 00 France, and would comply with all the required

91,000

05,000 conditions except that of being of home pro

99,000
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$8,061) 00 duction, This difficulty the board overcame

1,211

107,575 00 by stimulating the cultivation of the plant

.96

109,252 50 and the manufacture of the oil from its seed

71,159 90 as a private industry.

55,-05 20 In 1861 the board purchased and used over

44,000 5,000 gallons of colza-oil at $1.10 per gallon; in 1862, 2,000 gallons at $1 per gallon, and 10,000 The lighthouse establishment from its incepmore at $1.10 per gallon, and that, too, while tion had a tendency to the use of petroleum. sperm-oil was selling at $1.641 per gallon; As early as 1807 there was a correspondence and it speedily became evident that the coun between Mr. Gallatin, then Secretary of the try would soon supply all the colza-oil wanted Treasury, and the owners of the good ship for lighthouse consumption at $1 per gallon as Corlomande, from Rangoon, in the kingdom il maximum price.

of Ava, relative to five thousand gallons of Meantime the board had experimented with earth-oil, which is commended as the “ best Jard-oil, and with such success that it appeared article known for burning in lighthouses, makthat this oil of a certain grade was a more de- ing a very strong, clear, and bright Hame, sirable illuminant than colza, and it gave equal- emitting at the same time a great rolume of ly good results, was more certain in quantity smoak.” It may be that then, as often since, and production, and was economical in price. great volume of smoak” prevented the

The principal manufacturer, who, after ser use of the earth-oil. In 1855 the board made eral attempts, had succeeded in making colza some unsuccessful experiments with the varioil, and who to do so had put up expensive ma ous forms of petroleum. Meantime the price chinery at the board's instance, finally in- of lard-oil had so far increased that a cheaper formed it that the result of its experiments illuminant became a necessity. It was only had convinced him that the Government could necessary, however, as a matter of economy, not afford to use colza-oil in preference to lard- since lard-oil bad proved itself acceptable in oil, and that he would abandon its further man every other respect. The matter was apqfacture for lighthouse purposes, though he proached with much caution, as the volatile, inhad demonstrated its success in all respects Hammable, explosive nature of mineral-oil was escept competition with lard-oil, if the board well known. The keeper of one of the lights would purchase from him the colza be tlien on Lake Michigan had, in 1864, on his own had on hand. This was done, and lard-oil be- motion, substituted for the usual lard-oil lamp came the established illuminant.

one burning kerosene. Soon after commenc

1967. 1569. 1.56.J. 1970. 1571 1972 1571. 1974. 1-7). 1876. 1877. 1973. 1879. 1350. 1551.

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85,000 110,000 107,000 106,000 67,000

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the ho

ing its use, he attempted to extinguish the lamp throughout the lighthouse establishment, exby blowing down its chimney, when it exploded. cept in the seventy-three lights of the highest He had scarcely reached the foot of the stair- powers, in which this illuminant fails yet to case, with his clothes on fire, when another burn to as good advantage as does lard-oil. It explosion took place, which blew the whole is claimed that five gallons of mineral-oil will lantern from the tower, and effectually de- give as much light as four gallons of lard-oil, stroyed the lenticular apparatus. But, as min- while mineral-oil at the present writing costs eral-oil was, in one form or another, in suc abont fourteen cents and lard oil about sevencessful use in European lighthouses, the board ty-five cents per gallon. Thus it may be stated set about solving the problems connected with roughly that mineral - oil, as compared with its uniform and economical combustion, its lard-oil, gives one fifth more light and costs purchase in the large quantities needed, the four fiftbs less money. tests as to purity, and the degrees of heat at The propriety of using gas as a lighthouse which it should burn and flash, the degrees of illuminant has several times been considered. cold at which it should remain limpid, meth- An effort was made in 1944 to use a rosin gas ods for its transportation and storage, and the at the Christiana light station, near Wilmingother questions connected with its safe and ton, Delaware, but, after something less than economical use.

a year of trial, it was abandoned as impractiThe first difficulty was that of the lamp in cable. Another unsuccessful attempt was afwhich it should be burned. At the outset a terward made at the light station on Reedy claim was set up that mineral oil could not be Island, mouth of Delaware River. burned in a lighthouse without infringing on a From time to time, lighthouses near cities certain patent. The board, always ready to have been illumined with gas from the city encourage inventive genius when applied to gas-works: it is now used in but three stations, lighthouse matters, asked the necessary au- namely, Cleveland, Ohio, Alexandria, Virginia, thority to deal with the patentee, when the and Newburyport, Massachusetts; and even Secretary of the Treasury, as the custom is, at these three it has been found necessary to referred the legal questions involved to the guard against the accident to gas-pipes, most Attorney-General. Thus a legal controversy likely to happen in the coldest weather, by keeparose which continued some three years, run- ing a set of oil-lamps ready to take the place ning through the Patent Office, and was finally of the gas-burners at a moment's notice. But, adjudicated in the courts, where it was decided while the board has not found the use of gas that mineral-oil could be burned in any light- practicable thus far, it keeps itself informed as house lamp except one without infringing any to the progress made in its manufacture and patent. Meantime, the board had, after much its combustion. experimentation in its own laboratory and work The board is using compressed gas to light shops, succeeded in producing a mineral-oil the ten lights at the northern entrance to Curlamp capable of consuming all the carbon it ritnck Sound, North Carolina. This gas is made set free, and introduced it into its lighthouses and compressed at its own gas-works, and it

The chairinan of the board, the venerable is carried to each of the beacons in tanks, built Professor Henry, had been during this time into a scow, which is towed by a steam-launch, dealing with other difficulties practically and manned by the keepers of these ten small personally in laboratory and workshop, and in lights, who reside on board. The gas in each them had more than once endangered his per- will burn for ten days and nights, if need be. son, if not his life, and thus the board reached Though the action of this illuminant is not in advance certain determinate results. It unsatisfactory, it can hardly be said that it fixed the flashing test of the mineral-oil that has yet passed beyond the experimental stage. would be accepted for lighthouse use at 140° The board has watched the experiments Fahr., the fire test at 154°, and the freezing made in other countries with the electric light test at which it should remain limpid at zero. as a lighthouse illuminant, and, while it does Litmus paper immersed in it for five hours not consider that this light can be seen farther must, by remaining unchanged in color, show than its own best lights—which are seen, loits freedom from acid; its specific gravity cated, and identified as far as the currature must not be less than 802° ; and it is to be of the earth will allow and while it is not conpaid for by weight, at the rate of 64, pounds vinced that the electric light can be located or net weight to the gallon. The board has identified better, or even seen in fog farther, contracted for several lots deliverable at dif- than its oil lights, still, for purposes of practiferent periods at New York, Detroit, and San cal experimentation, it has – unsuccessfully, Francisco, amounting to 75,000 gallons in all, however-for several successire years, asked at an average price of 14 cents per gale Congress for such an appropriation as would lon. The difficulty of storing and transport- enable it to erect and put in operation an elecing such quantities in bulk was conceded, but tric light by the side of and in competition its danger was evaded by having the oil placed with an oil light. Meantime it has tested at once in fire-gallon cans, where it was to every prominent American-built machine for remain until transferred to the lighthouse burn- making tho electric light, that it might be ers for combustion. Mineral-oil is now used ready to use the best when Congress had pro

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