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show a straight line on the side towards the light, and a serrated edge on the opposite. These sixteen lenses, thus secured between two rings, the lower one is supported on eight bars that curve out around the lower mirrors, and then curve in again to another ring, which is connected with the machinery by which the revolving motion is secured. Below the lenses are four circles, and above them seven, on each of which are 28 mirrors. Of this magnificent light the writer from whom this description has been condensed,* says,

"To the stranger who visits the Barfleur light, this assemblage of 308 mirrors and 16 large lenses, surrounded by 16 windows of plate-glass, more than 10 feet high, all polished to the highest degree of perfection, and all concentrated within the small compass of the lantern, presents one of the most brilliant exhibitions that the arts can furnish, especially when, in addition to this, he feels the effect of standing 236 feet above the level of the ocean, without any thing to prevent falling out; for the plateglass of the windows is scarcely perceptible, although so strong that the largest sea-birds cannot break it, but frequently fall dead by the blow when, flying towards the light, they come with full force against the glass. The stranger on entering from the darkness below, is taken by surprise, and, for a while, afraid to move, lest he may touch on one side or the other, and the apparently

frail fabric crumble under his hands."

The French lenticular lights, which are thus recommended by their superior illuminating power, are also represented as being far more economical than the English reflectors. The writer in the Edinburgh Review, to whose able article on this subject we have already referred, shows by a comparative statement of the expense of each, that a revolving LightHouse could be originally fitted up with lenses for £1025, while a revolving light

with reflectors would cost £1500—making a difference of £475 in favor of the lenticular system. But even were the original cost to be greater instead of less, it is evident that lenses would be far more desirable than reflectors; that trimming and cleansing them would be far less expensive; and that, in this way, the amount annually saved in current expenses and repairs, would soon overbalance the original loss. But there is good reason to believe that a still more decided saving would be effected in the expense of oil, by the substitution of lenses for reflectors. It will be recollected that upon testimony already introduced, one Argand burner with a single lens, gives a light equal to nine reflectors, fitted with nine argand burners. At the same time Mr. Stevenson, in his Report on the experiments at Gulan Hill, says that "a powerful lamp is used for the lens, which consumes oil equal to the supply of fourteen Argand burners." The saving effected here will readily be seen. In a Light House of the first order furnished with reflectors, there are ten on each of the three sides, making thirty reflectors, to be supplied, of course, with thirty lamps. In one of the same order furnished with lenses, a single burner, consuming only the oil of fourteen lamps, would be sufficient. Here, then, we should have the light of thirty lamps, at the expense of fourteen, and the economy would increase with the brilliancy of the light.†

The opinion of Sir David Brewster with regard to the expediency of substituting lenses for reflectors, was expressed in the most decided terms in his communications to the lens committee of Parliament. In one of them dated February 23, 1833, after stating that the superiority of lenses was "no longer a matter of opinion," since it had been proved that a single lens was equal to at least nine 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.

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 60,673 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 the advantages of the lenticular system: "The revolving light with lenses will consist of two lenses, placed opposite to each other, and illuminated by a single lamp between them.

"The revolving light with reflectors will consist of 18 reflectors with argand burners, nine reflectors, being substitutes for each lens.

"It being admitted that these two pieces of apparatus will give the same light, let us consider their comparative advantages.

"1. The lens apparatus will be decidedly the cheapest in its first cost, and the lenses will never require to be renewed. "2. The lens apparatus will not require one-third of the labor in cleansing and arranging them daily for use.

3. The lens apparatus will not require so strong and powerful a piece of machinery to move it, from its inferior weight and greater compactness.

4. The lens apparatus may be placed in a much smaller light-room, the 18 reflectors requiring a very large space; and economy might thus be introduced in the erection of future Light-Houses.

5. The 18 argand burners will decidedly consume more oil than the simple compound burner used for the lenses; hence, it follows that the lens apparatus is in every respect better and more economical than the reflector apparatus.”

Under testimony so explicit and authoritative as this, (and much more might be introduced had we space,) no doubt can well be entertained that the lenticular system is the farthest advance science has yet made in perfecting the methods of Light-House illumination. It concentrates, far more perfectly than any other method, the rays of light which have been created, and gives them, more nearly than any other, precisely that brilliancy and direction which will best answer the purpose for which such beacons are erected. One of its most prominent recommendations is, that it affords special advantages for establishing what we greatly need, systematic and efficient distinguishing lights, which the mariner can so readily distinguish from one another as to be able at once to name the beacon, and thus to ascertain his precise position.

This is, evidently, a matter of the first importance: and the utter lack of any such provision in the Light-Houses of this country, has led to many very sad disasters. In 1840 the schooner Delaware stranded on Scituate beach, on the Massachusetts coast, from having been unable to distinguish Scituate Light from that at Boston; and in the same year the schooner Perse ran ashore in the same spot, and from precisely the same mistake. Utter confusion pervades the arrangement of our Lights on nearly every portion of our extended coast.

Many methods have been devised to give an individual and easily recognizable character to each individual light. The method in general use in Great Britain, at least until very recently, was that of giving different colors to the lights, by coloring the glass through which the found seriously to impair the brilliancy rays were obliged to pass; but this was and effect of the light itself. Dr. Brewster, in a communication to the Parliamentary Committee, dated March, 29, 1833,* speaks of a discovery he had made, whereby a numerical character could be impressed on any light, which nothing could change, and which could easily be recognized by looking at the light through a small and cheap apparatus made for the purpose. This, in its theory, would evidently best answer the end desired; but its practicability has never, we believe, been demonstrated; and the French method is probably the best now in use. It consists simply in so arranging the lenses, in the revolving apparatus, that eclipses shall occur at regular intervals; and the intervals are of different duration in different Light-Houses. Thus, in one a brilliant flash may be visible twice in a minute, in another three times in the same interval, &c. A master, therefore, has only to inform himself of the character of each light, and then determine, by his watch, the duration of the eclipses, to understand at once his precise position. This is the method adopted by Fresnel; and it is undoubtedly much the best ever used. It is due to 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

that it should be more generally adopted in the Light-Houses upon our coast. With this general view of our LightHouse System, we must leave the subject. Every person, acquainted with its character, must concede that it requires improvement. In a few cases, new lights, and in many cases better lights, are greatly needed. Lenticular lights of the second order, were imported from France in 1840, and set up at the Highlands of Neversink. Their economy has never been fairly tested, as the results of their use have been cautiously kept from the public eye; but every shipmaster who has entered this port since their erection, will bear prompt testimony to their superior brilliancy and efficiency. A few others of the same kind, are greatly needed along our coast. At Cape Hatteras, on Carysfoot Reef, and especially at Tortugas, the great turning point of all the navigation in and out of the Gulf of Mexico, lenticular lights of the first order should be erected. One of the second class should be placed on Cape Canaveral, another on Cape Florida, and a third on the Key Sombrero.

But our whole System lacks method; and nothing can ever supply this radical defect, until Science and Experience are systematically introduced into its supervision. The establishment is not adapted either to the wants of our commerce, or to the advanced state of science and of art. And yet, in all other branches of industry and social economy, we are prompt to seize upon all improvements. We use the very best steam engines, the best machinery in manufactures, and even the Magnetic Telegraph, the latest achievement of science in the transmission of intelligence, is usurping the place of the mail coach and the locomotive. In these departments we should rightly deem it niggardly and narrow to reject the new because the old was cheaper. There, certainly, is no reason why similar improvements should be rejected or neglected, in so important a branch of the public service as our Light-House Establishment, a branch on the efficiency and perfection of which depend, not only the wealth with which our ships are freighted, but the lives of the thousands who follow the sea.

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 Health. By AMARIAH BRIGHAM, M.D. Philapelphia: Lea & Blanchard.

THIS is the title of a small volume by Mr. Brigham, now Superintendent of the Lunatic Asylum at Utica. It was pub lished some years since, and was soon republished in Scotland, where it met with commendations from men of the highest intelligence. It discusses in a brief and lucid manner a variety of topics of the deepest interest to every parent and every student. He settles at the outset, the brain to be the material organ of the mind, from experiments that have been made upon the brain itself. Having established the connection between the material organ and the mind, he describes the state of an infant's brain, which from its mere physical condition condemns high or constant mental stimulants. Mr. Brigham's remarks here are excellent, and founded, in our opinion, in the closest practical wisdom. Especially in this country do we need instruction on this point. The steam-spirit is carried into everything, and we hurry our children into the mental excitement of study, thinking the sooner they begin and the harder they are driven, the more they will know. In the first place, this is not true. The best minds are not those which are early forced or early developed. In the second place, its want of truth is not its greatest objection. If it were a negative evil it might be endured. But this forcing the mind into unnatural action in infancy, acts on the body and lays the foundation of those after diseases of the nerves and heart that torture the life. Physical education has been left to take care of itself, and the result is-instead of securing vigorous minds, we are cursed both with weak minds and weak bodies. Take the life of our students and we find the greatest mental labor is required of them when they are least able to perform it. But the laws which govern our physical and spiritual natures do not clash, and the mental excitement the more matured mind loves, is favorable not only to its own growth but the health and strength of the brain itself. We cannot agree with Mr. Brigham, however, in placing the chief causes of dyspepsia in the brain, physician though he be, for if there be one fact palpable to the most common observer, it is that this most annoying of all diseases is almost universally brought on by bad diet and sedentary habits, rather than overtasking the mind. The nerves are affected, not because the brain, the center of them,

is diseased, but because the stomach, the receptacle of so many of them, has become irritated and inflamed. The stomach is not irregular because the brain has become unsteady, but the brain is disordered because the stomach no longer performs its appropriate functions. The latter acts on the former through the nerves that pass from one to the other.

This little book aims at no display of learning, nor does it weary the reader with long and tedious discussions. Avoiding technicalities, it seeks by the simplest and shortest method to secure the welfare of all. We cannot, in the few lines we devote to it, present half its merits. We can only express our convictions of the truth of its observations and the soundness of its logic. Its value was felt in Scotland, but it is far more important to us who are subject to more constant and higher excitement than any nation on the globe. This very excitement in ourselves and all around us, communicates itself to our systems of instruction and early training, and we task the mind in its first early struggles beyond its feeble powers, and not only disturb its balance but that of the whole physical system. The connection between a healthy state of mind and body, are made apparent by Mr. Brigham to the most unlearned reader. The influence of such works cannot be otherwise than healthful, and it is to them we attribute the change that has taken place within the last few years in public sentiment upon the subject of education.

The chapter devoted to the causes of so much insanity in this country, possesses equal interest with those upon education. We believe that with no more precaution than has heretofore been used, we shall become an anomaly among nations in this respect. The inhabitants of other countries are often subjected to great excitement, but only for a limited period and with long intervals of quiet. But here it begins in childhood and continues till death. It is not caused by the introduction of disturbing elements into our social and political system, but is a necessary part of them.

As head of the State Lunatic Asylum, Mr. Brigham's views of the causes of insanity in our country deserve attention, and we subjoin his summing up of his remarks on this point. The following he gives as the chief causes of insanity in the United States :

"First. Too constant and too powerful excitement of the mind, which the strife

for wealth, office, political distinction, and party success produces in this free country. "Second. The predominance given to the nervous system by too early cultivating the mind and exciting the feelings of children.

"Third. Neglect of physical education, or the eager and proper development of all the organs of the body.

"Fourth. The general and powerful excitement of the female mind. Little attention is given, in the education of females, to the physiological differences of the sexes. Teachers seldom reflect, that in them the nervous system naturally predominates, that they are endowed with quicker sensibility and far more active imagination than men; that their emotions are more intense and their senses alive to more delicate impressions; and they, therefore, require great attention, lest their exquisite sensibility, which, when properly and naturally developed, constitutes the greatest excellence of woman, should either become excessive by too strong excitement, or suppressed by misdirected education."

Every one who has reflected on this subject and observed the effect of the constant stimulants our whole system of life furnish to the mind, and the, hitherto, almost utter neglect of physical education, must agree with Mr. Brigham in these remarks. A table is given at the close of the book of the ages of some 300 different literary men of ancient and modern days. Of this large number the two extremes are 50 and 109, making, as it will be perceived, an average nearly if not quite equal to the allowed threescore years and ten, thus showing that mental activity is not adverse to longevity. The connection between the mind and body, and the proper and equal development of both in childhood and youth, are, as yet, but little understood, and we hail the circulation of such works as the one before us with unfeigned pleasure. Prevention is better than cure, and the common sense which shuns evils, is of more practical value than the highest skill in effecting their removal when once incurred.

ed, the author takes up Rome in detail, and goes through the several departments of sight-seeing, methodically. He sees everything with his own eyes, and gives us his own impressions of the different objects that crowd with such rapidity on the spectator. St. Peters awakens all his enthusiasm, and he stands and gazes on that great temple with feelings of intense admiration. The Vatican with its wealth of statuary-the churches with their rich architecture and choice paintings-the palaces with their gems of art, come and go with great distinctness as the reader follows Mr. Gillespie in his rambles over the city. The Capitol and ancient Forum---the Palatine and Coliseum, stand out in strong relief in his picture. Art and artists receive also his attention; and Mr. Crawford draws from him a long eulogium on that artist's genius and works. It is well merited, though we cannot agree with Mr. Gillespie in his views of the proper scope of the American artist. We believe no man will obtain abiding fame, who follows merely in the track of the great masters. The modern sculptor cannot embody the form of cassic beauty in so great perfection as the classic sculptors. A man of genius should study the works of the old masters, not to rival them, but to use the knowledge and beauty he derives from them to embody the sentiment and spirit of the age he lives in. Genius creates rather than imitates, and, instead of believing that art has exhausted life of its forms or expressions of beauty, feels that it has only opened the portals to the great temple within.

Modern Rome,-its inhabitants-their customs and character, even to their restaurateurs and dishes, occupy also his attention. The style of the book is easy, finished, and agreeable. If it had less of the guide book arrangement it would please us better. It is not sufficiently impulsive to please the enuthusiast, but it is never stupid. It presents, on the whole, an excellent picture of Rome, as one finds it now, minus, its fêtes and great religious 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.

This is the title of a volume written by Mr. Gillespie, of New York, designed as a surface sketch of Rome as it. The book opens with the shout of Roma! Roma!' by the postillion, and we find ourselves suddenly passing into the Eternal City. After the enthusiasm of the first moment is pass

neat style, such as the contents merit; and no one will rise from its perusal without knowing more of Rome than he knew before.

We would like to make some extracts, exhibiting the style of the author, and the manner the different objects he describes, are presented to the reader, but must deny ourselves the pleasure for want of room.

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