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THE SEA-LAMPREY. (Petromyzon marinus.) THE Lamprey tribe constitutes the last family of the fishes with a cartilagenous skeleton. There are four known British species; that figured above, which is found in salt-water, and three inhabitants of fresh water, namely, the Lampern, Petromyzon fluviatilis; the Fringe-lipped Lampern, Petromyzon planeri; and the Sand-Pride or Mud Lamprey, Ammocætes branchialis. The Sea-Lamprey is found in all the seas of Europe, from the Mediterranean as far north as Scandinavia and Iceland; it is also met with in North America. In Spring and Summer this species frequents the mouths of most of our rivers, and ascends the stream for a considerable distance, for the purpose of depositing its spawn. Sir William Jardine says, speaking of the Scotch rivers, "They ascend our rivers to breed about the end of June, and remain until the beginning of August." They are not furnished with any elongation of the jaw, 'afforded to most of our fresh-water fish, with which the latter form the receiving furrows at this important season; but the want is supplied by their sucker-like mouth, by which they individually remove stones or other substances. Their power is immense; stones of a large size are removed by them, and a large furrow soon formed. This species remains in pairs, two in each spawning-place, and while there employed, retain themselves affixed to a large stone.

The right-hand figure below shows the flexible lip, concealing the mouth; the figure on the left hand represents the rounded mouth, the small and numerous tubercular teeth, and the central opening leading to the throat and stomach.

The Lampreys, like the sharks and rays, have no swimming-bladder, and being also without pectoral fins, are usually found near the bottom of the water. To save themselves from the constant muscular exertion which is necessary to prevent their being carried along by the current, they attach themselves by the mouth to stones or rocks, and from this circumstance they obtained the name of Petromyzon, Stone-sucker. The food of the Lamprey consists generally of any soft animal matter; and in the sea it is known to attack fishes even of large size, by fastening upon them, and with its numerous small, rasp-like teeth, eating away the soft parts down to the very bone.

The Marine Lamprey usually measures from twenty to twenty-eight inches in length. In slowly-running

water, the Lamprey swims with a lateral undulating motion of the body, assisted by its fins; where the current is rapid, it makes successive plunges forward, attaching itself quickly to any fixed substance that offers, to secure the advantage gained.

Pennant states that it has been an old custom, for the city of Gloucester annually to present the sovereign with a lamprey-pie, covered with a raised crust.

The Fresh-water Lampern is about half the size of the species just described, and is believed to remain in the rivers it frequents throughout the whole year. It is considered in best condition from October to March. Formerly it was in great request among the Dutch fishermen, as bait for turbot, cod, &c.; but the great demand so raised the price by making the fish scarce, that other substances have been resorted to. In the course of one season as many as 400,000 have been sold for bait, at 40s. per 1000. Formerly the Thames alone supplied from 1,000,000 to 12,000,000 Lamperns annually.

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THE USEFUL ARTS. No. XXXV.

THE CARPENTER.

FOLLOWING the plan we have laid down, we shall first describe the principal materials made use of, by this most important of all mechanics. It is obvious that in every country the timber is employed that is either indigenous, and adapted to the work to be done, or which can be procured most readily from other countries. In Britain the OAK, of which we have two species and several varieties, first and most important of all trees is, of course, our own belonging to the genus Quercus. It is far less used in civil architecture than formerly, although there are certain purposes in building to which it is still applied: but owing to its value, and the demand for it for ships, and to the great labour required to work it, its place is now supplied by fir. The best oak is that which grows on cold, stiff, the colder the climate, or the higher above the level of the clayey soils, and is the slowest in arriving at maturity; and sea the tree grows, provided it be not stunted from severity of climate, the better the timber; hence Scottish and Welsh oak is more esteemed than that from the middle or southern counties of Britain. Our own island does not produce this timber in sufficient abundance to supply the demand, and large quantities of oak are imported from There are four kinds of oak used in the Royal Dock-yards, different countries, especially from Prussia and Canada. Welsh, Sussex, Adriatic, and Baltic, besides two others termed African oak, employed in different parts of the vessels, according to the qualities requisite for the particular purpose. Next to our own oak, that from the shores of the Baltic is by far the most esteemed.

In domestic architecture oak is only used in the largest and best buildings, occasionally for the principal beams; but its chief use is for door and window frames, cills, sleepers, king-posts of roofs, for trussing fir girders, for sashes, for gates of locks, sluices, posts, piles, &c. The timber called African oak, used in the navy, is wood of a different genus.

TEAK is the produce of a tree of the genus Tectona. Valuable as teak is found to be in ship-building, it has not yet been used in domestic building to any extent. From sixteen to eighteen thousand loads of teak are annually imported into Britain from India, principally for the Royal Dock-yards, this wood being used for certain beams and pillars in ships.

WAINSCOT is the wood of a species of oak, imported from Russia and Prussia in a particular form of log FIR, or PINE, ranks next to oak for its valuable qualities, and if its universal application be taken into consideration, it might be thought even superior in importance. The finest fir is that from Norway, Sweden, Russia, and the Baltic generally, the vast mountainous tracks of which countries are covered with dense forests of various species of pine. The best of these is the Pinus sylvestris, called also in Britain the Scotch Fir, from its growing in great perfection in the northern portion of our island. The fir from the southern shores of the Baltic, the timber from which is known as Memel, Riga, or Dantziç fir, from the several

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localities whence it is imported, is next in value to that from Norway. Large quantities of fir timber are also annually brought from Canada, but this timber is greatly inferior to the European.

DEAL is the name given to the timber of the pine, when sawed into planks, in which form it is imported into this country from the north of Europe. Deal is the produce of the Pinus abies, Pinus alba, and Pinus nigra, and the best is that obtained from Christiana.

Fir timber is used for every part of houses, and extensively in ship-building, in the fittings-up, while it constitutes the only material for masts, for which purpose its lightness, and the great length and straightness of the trunk, peculiarly fit it.

Pine, or fir, is imported into this kingdom under the various names of timber, battens, deals, laths, masts, yards, and spars, according to the size or form into which the tree is sawed. It is called timber when the tree is only squared into a straight beam of the length of the trunk, and from not less than eight or nine inches square, up to sixteen or eighteen square; fifty cubic feet is a load of timber. Deals vary in length and thickness from eight to sixteen feet, eleven inches wide, and from one and a half to three and a half inches thick. Four hundred superficial feet of one and a half inch plank makes a load. Battens are small long pieces of fir about three inches wide and one inch thick. Masts, yards, and spars, are the trunks of small trees simply barked and topped.

BEECH is partially employed in ship-building for the keel and timbers near it; but it is not at all employed in civil architecture. The principal use made of this wood is in the construction of machines, mill-work, lock-gates, &c., and for handles to tools; it is also a good wood for the turner, being of a close grain. It will not, however, bear alternations of moisture and dryness, and is liable to be attacked by worms, so that it is not extensively employed. CHESTNUT belongs to the same order as the beech, but although a valuable wood, it is now little, if ever, used. Formerly it was extensively so, and the roofs of several ancient buildings are constructed of it. From some experiments, indeed, it seems to be as durable as oak itself.

ASH is the wood for the wheelwright and the maker of agricultural implements; it is one of the most valuable of all timber trees, combining great strength with elasticity and lightness; it, however, splits easily. Ash is not used either by the shipwright or the common carpenter.

ELM is a coarse-grained wood, but strong and durable; it does not work readily, and is therefore but little used. It is, however, employed for certain parts of ships, and for making casks, chests, coffins, posts for mill-work, and a few other purposes.

Next to oak and fir, the foreign wood MAHOGANY is by far the most valuable, and that most extensively used; it is the growth of the West Indies and South America, and the tree, the Swietenia mahogani, is, perhaps, the most majestic of all timber-trees for the enormous dimensions its trunk attains, its vast height and size, and its dark beautiful foliage. The mahogany of the island of Cuba, and that from the bay of Honduras, is first in estimation. There are two East Indian species, but they are not imported in any quantities into this country.

The best mahogany is that which grows in dry, cold, and exposed situations. Such wood is fine-grained, hard, and dark in colour, richly variegated, causing it from its beauty to rank among the most ornamental of fancy woods, while the light, coarse-grained wood, which grows in warm moist climates is sufficiently abundant to be used for ordinary purposes, and yet possesses admirable properties for all, where no great strength or tenacity is wanted.

Within the last twenty years the use of this wood has increased amazingly, and some ships have many of their upper timbers above the water-line constructed of Honduras mahogany. Its use in furniture and cabinet-making is well known, and, indeed, it may be said to be the principal wood used for this purpose, and to have entirely supplanted our own walnut, which was formerly in universal use for the same purposes.

The woods above enumerated are those most extensively or largely used by the carpenter; but there are several others employed for small articles, and for particular purposes, which deserve mentioning.

Box is the wood of the Buxus sempervirens, a hardy evergreen plant, indigenous in all the southern parts of Europe and Western Asia, and long domesticated in our shrubberies. Box is especially the wood for turning, it

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being closer-grained, denser, and tougher than perhaps all others, except iron-wood, LIGNUM VITE, and one or two rarer woods. Box is used for rules, scales, and for small cabinet works; but that which gives it particular importance is its universal use for wood engraving.

LANCE is the name given to the wood of the Guatteria virgata, a tree indigenous to Jamaica, and one of the most important that are so, from the valuable qualities of its timber, lance-wood far exceeding our ash in lightness, strength, and elasticity; hence it is admirably calculated for shafts to carriages, handles to spears, and for all purposes where straight, light, flexible, and tough wood is required. It is neither so close-grained as box nor so hard, but it turns well, and does not split; in colour it is lighter than box.

EBONY is the name given to the wood of several different trees, which agree in being dark-coloured, dense, and durable; it is used for inlaying and for making rules or scales, as not being liable to warp. It is an excellent wood for turning, but except for these purposes, it is less in request now than formerly, when it was much used in cabinetmaking.

LIGNUM VITE is the wood of the Guaiacum officinale, a large tree indigenous in the West Indies. This wood is the hardest and heaviest known, and can only be worked in the lathe. It is much used for making the sheaves, or pullies of blocks used in shipping, and for friction rollers, &c.

There are a variety of foreign woods which, from their beautiful grain and varied tints, are used in-cabinet-making. But as these woods are too valuable to be used solid, they are sawed into thin leaves, called veneers, which are glued down on a backing of ordinary mahogany. The principal of these fancy woods are

ROSE-WOOD, which is produced by a tree, a native of Brazil. This wood is much used for furniture, both as a veneer, and solid for legs of tables, chairs, &c.

KING-WOOD is also the produce of Brazil; it is a dark chocolate wood, veined with fine black veins.

BEEF-WOOD comes from New Holland, is of a pale red even tint, and intensely hard and heavy. It is used for in laying and bordering.

TULIP-WOOD is a wood of a clouded red and yellow colour, and very hard, and used for bordering to larger woods. The tree is unknown to our botanists.

ZEBRA-WOOD is a large-sized tree, and abundant enough to be used as a veneer in large furniture, like rose-wood; it is more curious than elegant.

SATIN-WOOD is well known for its glossy yellowish tint, from which it derives its name; there are two varieties.

MAPLE, from our own indigenous tree, is a very elegant wood of a light colour, or else, near the root, variegated with knots and twisted grain. It is much used in fancywork.

Or the great number to whom it has been my painful professional duty to have administered in the last hour of their lives, I have sometimes felt surprised that so few have appeared reluctant to go to the undiscovered country “from whose bourne no traveller returns!" Many, we may easily suppose, have manifested this willingness to die from an impatience of suffering, or from that passive indifference which is sometimes the result of debility and bodily exhaustion. But I have seen those who have arrived at a fearless contemplation of the future, from faith in the doctrine which our religion teaches. Such men were not only calm and supported, but cheerful, in the hour of death; and I never quitted such a sick chamber without a hope that my last end might be like theirs.-SIR HENRY HALFORD. We know, and what is better we feel, inwardly, that religion is the basis of civil society, and the source of all good and of all comfort. We know, and it is our pride to know, that man is by his constitution a religious animal; that atheism is against not only our reason, but our instincts, and that it cannot prevail long. But if in the moment of rest, and in a drunken delirium from the hot spirit drawn out of the alembick of hell, (which, in France, is now so furiously boiling.) we should uncover our nakedness, by throwing off that Christian religion, which has hitherto been our boast and comfort, and one great source of civilization among us, and among many other nations, we are apprehensive (being well aware that the mind will not endure a veil) that some uncouth, pernicious, and degrading superstition might take place of it.—BURKE.

ON EMPLOYMENTS WHICH INJURE THE
EYE-SIGHT.
No. IV.

exempt a man from the penalties due to transgression : the disciple of Claude, or of Galileo-of Hunter, or of Watt, is exposed (as we shall see) in the exercise of his high calling to the inconveniences of the humblest artisan. Nothing, in fact, proves so well to us the MINERS AND COL- dependent and even coequal condition of man in the

LINEN-INSPECTORS BANK-NOTE INSPECTORS
BURNISHERS PAINTERS
LIERS-EFFECT OF HEAT UPON THE EYE-SIGHT
-CASTING OF STEEL-BURNING OF PAINTED
GLASS.

We now proceed to notice a few employments wherein too much or too little light proves injurious to the eye.

It is of course known that the value of cloth depends upon the fineness of its material, and the degree of closeness with which it is put together. In the process of weaving, the threads, whether of silk, cotton, or wool, &c., cross each other at right angles, and constitute what is technically termed the warp and the woof. The value of the cloth therefore is tested by the number of threads contained within a given space-the larger the number, the more valuable becomes the article. There is a class of persons called linen-inspectors, whose business it is to test the value of cloths in this way, and such persons suffer loss of visual power, in consequence of the constant application of the eye to this kind of work. Those engaged in examining white linen cloths suffer more than when dark colours are the subject of investigation; and among the coloured cloths the scarlet, with which our army is clothed, produces the worst effects. The reader is probably aware that white cloth reflects most light; and that of all the colours of the spectrum red is the least refrangible, and although yellow and orange colours afford most light, yet red affords most heat, and is, from causes not well understood, productive of irritability to the eyes of most animals. Scarlet is a compound colour, containing a large proportion of red, combined with yellow*. Manufacturers of bright colours also suffer injury to the eyes.

It is said also that at the Bank of England a new issue of bank-notes is productive of ocular disease among the clerks, whose employment it is to examine, sign, and counter-sign an immense number of these documents per day. The money counters also, in the same establishment, are said to be peculiarly liable to amaurotic affections, especially at every new issue of coinage, when the pieces are highly polished, and consequently reflect much light.

Burnishers form another class of persons peculiarly liable to this disease, particularly such as are engaged in producing upon metallic surfaces a high degree of polish. One of the results of the simple, and otherwise admirable, principle of the division of labour, is certainly attended in some cases with its evils, by splitting up one branch of business into a large number of collateral shoots, it reduces man to a machine, and often deprives him of the power of exercising his invention; and, as in this case, proves positively hurtful. Hence we have an additional proof of the value of automatic machinery in effecting those processes by which man is injured, and his powers impaired.

In the instances we have given, the hand and the eye are chiefly employed, while the mind rests; but Nature is not partial in her rewards or her punishments. A high degree of mental cultivation does not

The bull, the turkey, and other animals, manifest great impatience and anger at the sight of a red colour. This is probably due to an irritation of the optic nerve, induced by this particular colour : this is, however, only a surmise of the writer. A young man was recently killed by holding out his tongue to an adder which he had caught, and doubting whether it was a snake or an adder, put out his tongue to test the fact. The animal, irritated by the red appearance of the tongue, bit it; and the bite was fatal, for the young man died some hours afterwards.

scheme of creation as the universality and individuality of the application of the natural laws to which we are all alike subject. We have heard the case of an eminent landscape-painter, who in the ardent pursuit of his profession became troubled with confusion and dimness of vision. He abandoned his practice for a time, and gave rest to his eyes, the inflammation of which yielded to proper medical treatment. Upon attempting to resume his occupations he was much alarmed to find that he no longer possessed the power of discriminating shades of colour from each other : he had, in fact, apparently lost the faculty necessary to his profession. He had again recourse to medical treatment, and after a time was restored to perfect sight.

The above instances occur, as it will be seen, in employments where too much light is admitted to the eye, whereby it becomes irritated and fatigued. On the other hand its occupation in a dim uncertain light is productive of results equally disastrous. In this case it is strained as it were beyond its powers, in endeavouring to exercise its function in the absence of the only necessary means, namely, a moderate and steady supply of light. Such persons are the numerous class of miners and colliers, whose employment is underground, amid the fitful gleams of a few lamps or candles, which the very position of the workmen prevent from being other than weak and almost inadequate sources of illumination; while in the collieries the lamps are necessarily surrounded with wire-gauze to prevent the firing of the gas which often issues from the apertures (blowers) laid open by the workman's pick, and thus the already feeble illumination is enfeebled. The exposure then of the eye to this bad light for several hours, and the transition into the light of day above when the miners' daily toil is done, is in many cases productive of the disease we have described. In the stupendous mines of Southern America immense numbers of the natives were, while under Spanish dominion, kept entirely in the mines, together with their wives and children; and thus, as an ingenious Frenchman observes, those very persons whose ancestors worshipped the sun are born, live, and die, without ever having been blessed with a sight of his rays..

Ah! what avail their fatal treasures, hid
Deep in the bowels of the pitying earth,
Golconda's gems, and sad Potosi's mines;
Where dwelt the gentlest Children of the Sun ?

THOMSON.

The united effect of the dim light in which colliers are constrained to perform their daily labour, and of the contaminated atmosphere which they breathe, is thus alluded to by Mr. Thackrah, in his work on the Effects of Trades, Professions, &c. on the Health.

The eyes of colliers are small, affected with chronic inflammation, and intolerant of full light. Boys enter the pit at the age of six or seven, and are employed in opening the trap-doors, driving the horses, propelling the trucks, &c.; and finally, when of sufficient age, they become col liers. Sickness and vomiting sometimes affect persons at their commencing the employ, and many after a few years' trial are obliged, by the injury which their health has sustained, and especially by the weakness of the eyes, to leave

the mine.

(3.) As the exposure of the eye to too much light is injurious, it almost follows that too much heat is equally so. It is painful to reflect that many of our

luxuries are purchased at the expense of much hu- | man suffering. True it is that by habit men may become inured to extraordinary and unnatural circumstances, which do not indeed exert their fatal influence at once upon them, but which would sink an unaccustomed hand. Undoubtedly, by early use and training, the body may successfully withstand high degrees of heat, as the experiments of Sir C. Blagden, Chantrey, and others, and the every-day experience of our gas-factories, glass-houses, &c., prove; and it is possible that in all the successful cases the individuals are fitted peculiarly by nature, or the habit of early training, for the exercise of these pursuits; still, however, it is to be lamented that there are many cases of workmen whose powers fail them for their own peculiar callings. How far habits of intemperance influence their fate, it is not within our province to discuss, although we fear that much is to be attributed to this energetic and too

common cause.

On a visit a few years ago to an immense foundry, about noon on a hot summer's day, we were much struck by the situation chosen by several of the men for the consumption of their dinner. They were seated on the copings of several enormous forge-fires, the heat of which was so great as to prevent our approach within several yards, and yet these men appeared to suffer no inconvenience whatever, for as it would seem they were in a temperature natural to them, which, however, was so great that the broad sunshine, into which we soon went, appeared cool in comparison.

But the above instance of the power of the human frame to bear intense degrees of heat, sinks into insignificance when compared with many cases of constant occurrence in the arts and manufactures. We must be content at present with the selection of one only. The reader may be aware that steel is fusible, or capable of being melted, and when in the fluid state of being cast in moulds, by which process the natural qualities of the metal, its hardness and elasticity, and the permanence of the edge in cutting-tools, are very much improved. The steel which is to be cast is previously broken into small pieces, put into a clay crucible capable of holding between thirty and forty pounds of the metal, and so placed in a wind-furnace, where it is brought to a white heat, which is sustained for about four hours, in which time the liquefaction of the mass is complete the furnace-cover is then removed, and other preparations are made for pouring the metal into cast-iron moulds. "This is a process which places the melter in a situation little, if at all, enviable, as compared with the inside of M. Chabert's celebrated oven indeed the eyes and the hands that are daily conversant with molten steel would hardly shrink at the mention of a temperature sufficient to broil a beef-steak! Previously to drawing the crucible, the artist, whose body, arms, and legs, are defended by sacking-wrappers, goes to a water-trough, and with a besom thoroughly moistens his outer covering, that his clothes may not get a-flame, while he is bending over the mouth of the 'burning fiery furnace.' Thus prepared, with a pair of strong tongs he withdraws the pot from the fire, takes the lid off, and pours the metal into the mould. The ingot thus formed is either a bar about two inches square for tilting, or a plate six inches broad, twelve to eighteen inches long, and an inch thick, for rolling, as the same may be wanted to be wrought into its ultimate form by the hammer or the shears. It may perhaps be thought that this fluxing and pouring of the metal requires no very great skill in the management. It

is, however, a fact, that so much depends upon the most exact attention to a number of minute parti culars, only to be attained by a rare union of judg ment and experience, that a person who thoroughly understands the business is invaluable as a workman, and his earnings are accordingly great. Honourable instances are not wanting of these melters having become persons of property, not to say that they have set up their carriages! The importance of their avocation is indeed much greater than may generally be imagined, even when the best irons are used. Not only does the perfection of innumerable exquisite cutting instruments depend almost entirely upon the quality of the metal, but much of the glory of the fine arts. The steel plates, which by a wonderful triumph of skill the engraver has appropriated, the burine of Heath and the chisel of Chantrey, respectively owe their excellence to a judicious management of the crucible by the Sheffield cast-steel melter."-Manufactures in Metal.

A melancholy case has occured recently to a friend of the writer, an ingenious painter on glass and glassstainer. The stained glass which enters into the composition of church and cathedral windows, often containing pictures and figures of high excellence, is produced in the first instance, by applying a coloured composition to white glass, or painting on glass, as on canvass, with a coloured compost which will resist heat: the glass being thus prepared by the artist, its durability through long ages is ensured by a process termed firing, which consists in placing the glass in a close iron box or oven, called a muffle, and which is provided with horizontal iron shelves, placed at regular distances, and covered with well-burnt powdered lime, to prevent the contact of the glass and the hot metal. On these shelves the glass plates are deposited, the coloured surfaces of course upwards. The muffles are placed in a furnace, and each muffle is furnished with a tube, which passes out through the furnace-wall, the use of which tube is to enable the operator to examine the state of the glass during the process of firing. A fire is now kindled and heat continued until, on inspection, the glass contained in the muffle is found to have acquired a heat just sufficient to fuse it by this means the colours are absorbed into and become part of the glass. The watchful eye of experience alone detects the exact moment when the white heat, to which the furnace has been brought, must be reduced the whole contents of the furnace are left to cool gradually for about twelve hours, at the end of which time the glass is said to be annealed, or to have lost that brittleness which it would have had if it had been removed from the furnace immediately.

The gentleman referred to had been engaged for several years in managing the above process, when a few months back, after looking for a longer time than usual through one of the tubes into the furnace, while the contents of the latter were at a white heat, he entirely, and as it appeared to him suddenly, lost the sight of the eye he was employing. The retina was in fact struck with palsy, from which we regret to add he has not since recovered. And yet how wonderful is the fact, that although the eye in this case is totally insensible to luminous impressions, and at present is of no assistance to its owner, yet the pupil still retains to a certain extent its contractile and expansive power when light is more or less admitted to the visionless orb. This fact tends to show how independent the function of the iris is of the will.

In this class are included stokers in iron-furnaces and glass-houses, and the denizens of the smithy generally, together with tavern cooks, &c.

THE OVAL, THE ELEMENTARY FORM
OF BEAUTY.

THE indescribable beauty of outline which pervades many of the works of antiquity, has been the cause of many attempts to discover if there was any fundamental principle to which this peculiar beauty was to be ascribed. All parties seem to have agreed that it depends on various modifications of a curved line. Mr. Reinagle, the Royal Academician, endeavoured to show, in a lecture delivered at the Royal Institution in 1827, that ovals of various sizes would mechanically produce various elegant and symmetrical outlines. His endeavour was to prove," that a line formed by an elliptic curve was beautiful even in an abstract point of view, free from all association." To illustrate his views he employed various diagrams, such as are seen in the following figures.

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No. 1 and 2 are a series of straight parallel lines, arranged horizontally and vertically; these were shown to produce no principle of beauty. In No. 3, a series of straight lines are drawn so as to radiate from a centre producing the simplest beautiful arrangement of lines. In Nos. 4 and 5, he endeavoured to prove that a series of straight lines, radiating from centres, as fig. 4, were improved in beauty by the addition of curves, as in No. 5. Nos. 6 and 7 illustrate the improvement produced by substituting curves in the rays, as in No. 6, and a still further improvement by additional curves, as in No. 7. Pursuing the same idea, it was shown that if the rays proceeded from a curved instead of a straight line, as in Nos. 8, 9, the beauty of the arrangement was increased, No. 9 being the most elegant.

If an oval disk, fig. 2, is prepared, the beauty of the

Fig. 3.

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