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show a straight line on the side towards with reflectors would cost £1500-makthe light, and a serrated edge on the op- ing a difference of £475 in favor of the posite. These sixteen lenses, thus se- lenticular system. But even were the cured between two rings, the lower one original cost to be greater instead of less, is supported on eight bars that curve out it is evident that lenses wouid he far around the lower mirrors, and then curve more desirable than reflectors; that trimin again to another ring, which is con- ming and cleansing them would be far nected with the machinery by which the less expensive; and that, in this way, revolving motion is secured. Below the the amount annually saved in current lenses are four circles, and above them expenses and repairs, would soon overseven, on each of which are 28 mirrors. balance the original loss. But there is Of this magnificent light the writer from good reason to believe that a still more whom this description has been con- decided saving would be effected in the densed,* says,

expense of oil, by the substitution of

lenses for reflectors. It will be recollecTo the stranger who visits the Barfleur ted that upon testimony already introlight, this asseinblage of 308 mirrors and 16 duced, one Argand burner with a single large lenses, surrounded by 16 windows of lens, gives a light equal to nine reflecplate-glass, inore than 10 feet high, all po- tors, fitted with nine argand burners. At lished to the highest degree of perfection, the same time Mr. Stevenson, in his Reand all concentrated within the small compass of the lantern, presents one of the port on the experiments at Gulan Hill, most brilliant exhibitions that the arts can says that “a powerful lamp is used for furnish, especially when, in addition to the lens, which consumes oil equal to this, he feels the effect of standing 236 feet the supply of fourteen Argand burners.” above the level of the ocean, without any The saving effected here will readily be thing to prevent falling out; for the plate- seen. In a Light House of the first order glass of the windows is scarcely perceptible, furnished with reflectors, there are ten on although so strong that the largest sea-birds each of the three sides, making thirty cannot break it, but frequently fall dead by reflectors, to be supplied, of course, with the blow when, flying towards the light, thirty lamps. In one of the same orthey come with full force against the glass. der furnished with lenses, a single burner, The stranger on entering from the darkness below, is taken by surprise, and, for

consuming only the oil of fourteen lamps, a while, afraid to move, lest he may touch would be sufficient. Here, then, we should on one side or the other, and the apparently have the light of thirty lamps, at the erfrail fabric crumble under his hands." pense of fourteen, and the economy would

increase with the brilliancy of the light.f The French lenticular lights, which are The opinion of Sir David Brewster thus recommended by their superior illu- with regard to the expediency of substi. minating power, are also represented as tuting lenses for reflectors, was expressed being far more economical than the English in the most decided terms in his commureflectors. The writer in the Edinburgh nications to the lens committee of ParliaReview, to whose able article on this ment. In one of them dated February subject we have already referred, shows 23, 1833, after stating that the superiority by a comparative statement of the ex of lenses was “no longer a matter of pense of each, that a revolving Light. opinion,” since it had been proved that a House could be originally fitted up with single lens was equal to at least nine lenses for £1025, while a revolving light reflectors, he applies this result to the

Memoir of Lieut. Col. B. Aycrigg on the Light-Houses at Barfleur and Ostend House Doc. No. 190, 25th Congress, 3d Session.

7 In 1840 Hon. John Davis, on behalf of the Committee of Commerce, submited to the Senate a comparative table of the annual consumption of oil by the Light-Houses with reflectors, and those with lenticular glasses of corresponding range and brilliancy, prepared by the Superintendent of the construction of lenticular Light-Houses in France, Mr. Henry Lepaùte. Taking each Light-House in the United States, he gave first its range in nautical miles, the number of its sockets and its annual consumption of oil; and then gave the range in nautical miles, and the annual consumption of a lenticular lantern which might be substituted for it. The aggregate result showed that in 164 LightHouses with reflectors which consume 60,672 gallons of oil, lenses might be substituted so as to give a much greater average range, with a consumption of only 32,575 gallons. The table is incorrect in some minor particulars, but is well worth examining. - See Senate Doc. 474, 26th Congress, 1st. Session.

case of a revolving light, and thus states This is, evidently, a matter of the first the advantages of the lenticular system: importance: and the utter lack of any

“The revolving light with lenses will such provision in the Light-Houses of consist of two lenses, placed opposite to this country, has led to many very sad each other, and illuminated by a single disasters. In 1840 the schooner Delalamp between them.

ware stranded on Scituate beach, on the “The revolving light with reflectors Massachusetts coast, from having been will consist of 18 reflectors with argand unable to distinguish Scituate Light from burners, nine reflectors, being substitutes that at Boston ; and in the same year the for each lens.

schooner Perse ran ashore in the same “It being admitted that these two pieces spot, and from precisely the same misof apparatus will give the same light, let take. Utter confusion pervades the arus consider their comparative advantages.

“1. The lens apparatus will be decided- rangement of our Lights on nearly every ly the cheapest in its first cost, and the portion of our extended coast. lenses will never require to be renewed.

Many methods have been devised to “2. The lens apparatus will not require give an individual and easily recognizone-third of the labor in cleansing and ar- able character to each individual light. ranging them daily for use.

The method in general use in Great Brit“3. The lens apparatus will not require ain, at least until very recently, was that so strong and powerful a piece of machi. of giving different colors to the lights, by nery to move it, from its inferior weight coloring the glass through which the and greater compactness. “4. The lens apparatus may be placed found

seriously to impair the

brilliancy

rays were obliged to pass; but this was in a much smaller light-room, the 18 reflectors requiring a very large space; and and effect of the light itself

. Dr. Brews. economy might thus be introduced in the ter, in a communication to the Parliaerection of future Light-Houses.

mentary Committee, dated March, 29, “5. The 18 argand burners will deci- 1833,* speaks of a discovery he had dedly consume more oil than the simple made, whereby a numerical character compound burner used for the lenses; could be impressed on any light, which hence, it follows that the lens apparatus is nothing could change, and which could in every respect better and more economi- easily be recognized by looking at the cal than the reflector apparatus."

light through a small and cheap appaUnder testimony so explicit and au ratus made for the purpose. This, in its thoritative as this, (and much more might theory, would evidently best answer the be introduced had we space,) no doubt end desired; but its practicability has necan well be entertained that the lenticular ver, we believe, been demonstrated ; and system is the farthest advance science the French method is probably the best has yet made in perfecting the methods now in use. It consists simply in so arrangof Light-House illumination. It concen- ing the lenses, in the revolving apparatus, trates, far more perfectly than any other that eclipses shall occur at regular intermethod, the rays of light which have vals; and the intervals are of different been created, and gives them, more nearly duration in different Light-Houses. Thus, than any other, precisely that brilliancy in one a brilliant flash may be visible and direction which will best answer the twice in a minute, in another three times purpose for which such beacons are in the same interval, &c. A master, erected. One of its most prominent re- therefore, has only to inform himself of commendations is, that it affords special the character of each light, and then deadvantages for establishing what we termine, by his watch, the duration of greatly need, systematic and efficient dis- the eclipses, to understand at once his tinguishing lights, which the mariner can precise position. This is the method so readily distinguish from one another adopted by Fresnel; and it is undoubtedly as to be able at once to name the beacon, much the best ever used. It is due to and thus to ascertain his precise position. our commercial and maritime interests,

* See Parliamentary Report of 1834, Ap. p. 135.

† Though not strictly involved in our subject, it may not be unimportant to remark that our system of buoyage is quite as defective as our Light-House Establishment. In England the utmost care is taken to designate every buoy in every channel. Thus, on entering the port of Liverpool, if the master of a ship sees a red buoy marked “F. 1,” he knows at once that it is the first buoy of the Formby channel, and is to be left on the starboard side, going in. In the same way every one of them can be instantly recog

art.

that it should be more generally adopted But our whole System lacks method; in the Light-Houses upon our coast. and nothing can ever supply this radical

defect, until Science and Experience are With this general view of our Light- systematically introduced into its superHouse System, we must leave the sub- vision. The establishment is not adaptject. Every person, acquainted with its ed either to the wants of our commerce, character, must concede that it requires or to the advanced state of science and of improvement. In a few cases, new And yet, in all other branches of lights, and in many cases better lights, are industry and social economy, we are greatly needed. Lenticular lights of the prompt to seize upon all improvements. second order, were imported from France We use the very best steam engines, in 1840, and set up at the Highlands of the best machinery in manufactures, and Neversink. Their economy has never been even the Magnetic Telegraph, the latest fairly tested, as the results of their use achievement of science in the transmishave been cautiously kept from the pub- sion of intelligence, is usurping the place lic eye; but every shipmaster who has of the mail coach and the locomotive. In entered this port since their erection, will these departments we should rightly bear prompt testimony to their superior deem it niggardly and narrow to reject brilliancy and efficiency. A few others the new because the old was cheaper. of the same kind, are greatly needed There, certainly, is no reason why simialong our coast. At Cape Hatteras, on lar improvements should be rejected or Carysfoot Reef, and especially at Tortu- neglected, in so important a branch of gas, the great turning point of all the the public service as our Light-House navigation in and out of the Gulf of Establishment,-a branch on the effiMexico, lenticular lights of the first or ciency and perfection of which depend, der should be erected. One of the second not only the wealth with which our class should be placed on Cape Cana- ships are freighted, but the lives of the veral, another on Cape Florida, and a thousands who follow the sea. third on the Key Sombrero.

nized. There is no chance of mistaking them; and a ship in a fog, in falling in with one of them knows precisely her position and what belongs to it. We have no such method. The only difference that prevails is that of color, and this is without system, and often an embarassment rather than a guide. A naval officer, in writing information concerning a channel, once wrote—“ do not describe the color of the buoys, as they paint them of whatever color the Custom House contains.”

CRITICAL NOTICES.

Mental Cultivation and Excitement upon is diseased, but because the stomach, the

Health. By AMARIAH BRIGHAM, M.D. receptacle of so many of them, has become Philapelphia : Lea & Blanchard.

irritated and inflamed. The stomach is This is the title of a small volume by not irregular because the brain has become Mr. Brigham, now Superintendent of the unsteady, but the brain is disordered beLunatic Asylum at Utica. It was pub cause the stomach no longer performs its lished some years since, and was soon re- appropriate functions. The latter acts on published in Scotland, where it met with the former through the nerves that pass commendations from men of the highest from one to the other. intelligence. It discusses in a brief and This little book aims at no display of lucid manner a variety of topics of the learning, nor does it weary the reader with deepest interest to every parent and every long and tedious discussions. Avoiding student. He settles at the outset, the brain technicalities, it seeks by the simplest and to be the material organ of the mind, from shortest method to secure the welfare of experiments that have been made upon all. We cannot, in the few lines we de. the brain itself. Having established the vote to it, present half its merits. We can connection between the material organ only express our convictions of the truth and the mind, he describes the state of an of its observations and the soundness of its infant's brain, which from its mere phy- logic. Its value was felt in Scotland, but sical condition condemns high or constant it is far more important to us who are mental stimulants. Mr. Brigham's remarks subject to more constant and higher excitehere are excellent, and founded, in our ment than any nation on the globe. This opinion, in the closest practical wisdom. very excitement in ourselves and all around Especially in this country do we need in- us, communicates itself to our systems of struction on this point. The steam-spirit instruction and early training, and we task is carried into everything, and we hurry the mind in its first early struggles beyond our children into the mental excitement its feeble powers, and not only disturb its of study, thinking the sooner they begin balance but that of the whole physical and the harder they are driven, the more system. The connection between a heal. they will know. In the first place, this is thy state of mind and body, are made not true. The best minds are not those apparent by Mr. Brigham to the most unwhich are early forced or early developed. learned reader. The influence of such In the second place, its want of truth is works cannot be otherwise than healthful, not its greatest objection. If it were a and it is to them we attribute the change negative evil it might be endured. But that has taken place within the last few this forcing the mind into unnatural action years in public sentiment upon the subject in infancy, acts on the body and lays the of education. foundation of those after diseases of the The chapter devoted to the causes of so nerves and heart that torture the life. much insanity in this country, possesses Physical education has been left to take equal interest with those upon education. care of itself, and the result is—instead of We believe that with no more precaution securing vigorous minds, we are cursed than has heretofore been used, we shall both with weak minds and weak bodies. become an anomaly among nations in this Take the life of our students and we find respect. The inhabitants of other counthe greatest mental labor is required of tries are often subjected to great excitethem when they are least able to perform ment, but only for a limited period and it. But the laws which govern our phywith long intervals of quiet. But here it sical and spiritual natures do not clash, and begins in childhood and continues till the mental excitement the more matured death. It is not caused by the introduction mind loves, is favorable not only to its own of disturbing elements into our social and growth but the health and strength of the political system, but is a necessary part of brain itself. We cannot agree with Mr. them. Brigham, however, in placing the chief As head of the State Lunatic Asylum, causes of dyspepsia in the brain, physician Mr. Brigham's views of the causes of inthough he be, for if there be one fact pal. sanity in our country deserve attention, pable to the most common observer, it is and we subjoin his summing up of his rethat this most annoying of all diseases is marks on this point. The following he almost universally brought on by bad diet gives as the chief causes of insanity in the and sedentary habits, rather than overtask. United States : ing the mind. The nerves are affected, First. Too constant and too powerful not because the brain, the center of them, excitement of the mind, which the strife

for wealth, office, political distinction, and ed, the author takes up Rome in detail, party success produces in this free country. and goes through the several departments “ Second. The predominance given to of sight-seeing, methodically.

He sees the nervous system by too early cultivating everything with his own eyes, and gives us the mind and exciting the feelings of his own impressions of the different objects children,

that crowd with such rapidity on the spec“ Third. Neglect of physical education, tator. St. Peters awakens all his enthusi. or the eager and proper development of all asm, and he stands and gazes on that great the organs of the body.

temple with feelings of intense admiration. Fourth. The general and powerful The Vatican with its wealth of statuary-excitement of the female mind. Little the churches with their rich architecture attention is given, in the education of fe- and choice paintings—the palaces with males, to the physiological differences of their gems of art, come and go with great the sexes. Teachers seldom reflect, that distinctness as the reader follows Mr. Gilin them the nervous system naturally pre- lespie in his rambles over the city. The dominates, that they are endowed with Capitol and ancient Forum---the Palatine quicker sensibility and far more active im- and Coliseum, stand out in strong relief in agination than men; that their emotions his picture. Art and artists receive also are more intense and their senses alive to his attention; and Mr. Crawford draws more delicate impressions; and they, there. from him a long eulogium on that artist's fore, require great attention, lest their ex- genius and works. It is well merited, quisite sensibility, which, when properly though we cannot agree with Mr. Gillespie and naturally developed, constitutes the in his views of the proper scope of the greatest excellence of woman, should either American artist. We believe no man will become excessive by too strong excitement, obtain abiding fame, who follows merely in or suppressed by misdirected education.” the track of the great masters. The mo

Every one who has reflected on this sub dern sculptor cannot embody the form of ject and observed the effect of the constant cassic beauty in so great perfection as the stimulants our whole system of life furnish classic sculptors. A man of genius should to the mind, and the, hitherto, almost utter study the works of the old masters, not to neglect of physical education, must agree rival them, but to use the knowledge and with Mr. Brigham in these remarks. A table beauty he derives from them to embody the is given at the close of the book of the ages sentiment and spirit of the age he lives in. of some 300 different literary men of ancient Genius creates rather than imitates, and, and modern days. Of this large number instead of believing that art has exhausted the two extremes are 50 and 109, making, life of its forms or expressions of beauty, as it will be perceived, an average nearly feels that it has only opened the portals to if not quite equal to the allowed threescore the great temple within. years and ten, thus showing that mental Modern Rome,-its inhabitants-their activity is not adverse to longevity. The customs and character, even to their res. connection between the mind and body, taurateurs and dishes, occupy also his atand the proper and equal development of

tention. The style of the book is easy, both in childhood and youth, are, as yet, finished, and agreeable. If it had less of but little understood, and we hail the cir the guide book arrangement it would culation of such works as the one before please us better. It is not sufficiently im. us with unfeigned pleasure. Prevention pulsive to please the enuthusiast, but it is is better than cure, and the common sense never stupid. It presents, on the whole, which shuns evils, is of more practical value an excellent picture of Rome, as one finds than the highest skill in effecting their it now, minus, its fêtes and great religious removal when once incurred.

seremonies. It possesses high value to the traveller, while we know of no work from

which a mere reader could get a clearer Rome, as seen by a New Yorker. 1 Vol.

view of outer Rome. It is got up in a very Wiley and Putnam: New York.

neat style, such as the contents merit; and

no one will rise from its perusal without This is the title of a volume written by knowing more of Rome than he knew beMr. Gillespie, of New York, designed as a fore. surface sketch of Rome as it. The book We would like to make some extracts, opens with the shout of “Roma! Roma ! by exhibiting the style of the author, and the the postillion, and we find ourselves sud manner the different objects he describes, denly passing into the Eternal City. After are presented to the reader, but must deny the enthusiasm of the first moment is pass- ourselves the pleasure for want of room.

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