moral duties. He took the citizen at the moment of his birth, prescribed the manner in which he should be nourished and educated, followed him with directions through the different epochs of life, and flattered himself that he should make men free and virtuous. The penalty of death was to be inflicted for almost every crime, for homicide and idleness, for sacrilege and the stealing of garden herbs. The slightest offence, he said, deserved death, and he knew no punishment more severe for the greatest. He even carried his severity to a fantastic extreme, ordering punishment to be inflicted upon inanimate things, as for instance on a statue whose fall had injured a man. So violent a code could not last, and within 30 years Athens was again in anarchy. Recourse was then had to Solon, whose wisdom and moderation gave to the Athenians, not, as he himself said, the best laws, but the best that they were able to support. Draco died at the culmination of his glory upon the isle of Ægina. As he entered the theatre he received the acclamations of the people, and was stifled amid the mass of caps, robes, and cloaks, which they in accordance with their custom threw upon him as a mark of honor.

DRACUT, a post village and township of Middlesex co., Mass., on the N. bank of Merrimack river, opposite Lowell, with which it is connected by 2 bridges, 28 m. N. W. from Boston, and 16 N. E. from Concord; pop. of the township in 1850, 3,450; in 1855, 1,966, a portion of it having been annexed to Lowell in 1851. It borders on New Hampshire, and is traversed by Beaver river, which supplies it with water power. It is mainly an agricultural town, but in 1855 had 1 cotton mill manufacturing $62,000 worth of goods per annum, 1 woollen mill producing 475,000 yards of stuff, and 2 paper mills producing $10,500 worth of paper. In 1858 it contained 4 churches.

DRAFT, a word used indiscriminately with the synonymous term DRAUGHT, from which, according to Dr. Webster, it is corrupted. Although no less than 17 définitions are given in his dictionary, no mention is made in this or in Worcester's of the common use of the word to express a current of air; as the draft of a chimney to sit in a draft of air. In the former application it is also used to express quality, as a chimney of strong draft; so the word is used in the example given by Dr. Webster of a cart of easy draft, expressing "the quality of being drawn."

DRAGOMAN, an oriental word signifying interpreter. It is applied, in the Ottoman empire and the courts of the further East and of Barbary, to men who know several languages, and make it their business to act as interpreters between foreigners and the natives. What was formerly a necessity for commercial relations, has since become so for purposes of diplomacy. At Constantinople the office of prime dragoman, through whom the sultan receives the communications of Christian ambassadors, is one of the most important of the Sub

lime Porte, and is usually held by a Greek, belonging to one of the most illustrious families of his nation. Most foreign ambassadors and consuls in the ports of the Levant, and many travellers, keep private dragomans at their own expense.

DRAGON (draco, Linn.), an iguanian lizard, of the subfamily of acrodonts, or those having the teeth implanted in the bony substance of the jaws, to which they firmly adhere by the base of the roots. The head of these reptiles is triangular, flattened, and covered with small irregular scales, sometimes ridged; the small circular and tubular nostrils open at the end of the obtuse snout; the tongue is thick and spongy, with a round single extremity; the anterior teeth are 3 or 4, and resemble incisors; behind these the median ones are conical, like canines, and there are generally 2 pairs in each jaw; the posterior teeth, or molars, are tricuspid and compressed; under the neck is a long crest or dewlap, and on each side a triangular cutaneous fold placed horizontally, all 3 having in their thickness a process from the hyoid bone; there is generally a small cervical crest. While some species have no external ear, in others there is a small circular membranous tympanum. The neck is slightly compressed; the body has a central dorsal depression, and is covered above and below with small imbricated ridged scales. Dragons are at once distinguished from all other reptiles of this order by the horizontal expansion of the skin of the sides into a kind of wing, supported chiefly by the first 6 false ribs, which are extended horizontally outward instead of surrounding the abdomen. This flying membrane, of a semicircular form, is about as wide as the arm is long, free in front, but attached behind to the anterior part of the thigh; in a state of rest the animal keeps it folded like a fan along the body, and spreads it like a parachute to sustain it when leaping from branch to branch; it cannot be moved as an active organ of flight like the wing of a bird or the membrane of the bat, but serves only as a passive supporting instrument like the parachute membrane of the flying squirrel; both surfaces of this membrane are furnished with very small smooth scales. The fore and hind limbs, each with 5 toes, are of about the same length, the latter being flattened, with the posterior border fringed with serrated scales; there are no femoral pores; the tail is very long, slender, wide and flat at the base, round at the end, with rhomboidal imbricated scales, strongly ridged beneath. Among the species with a visible tyinpanum, and the nasal openings directed laterally, are: 1, the fringed dragon (D. fimbriatus, Kuhl), with the thighs fringed behind with triangular scales, and with longitudinal white lines on the wings; the general color above is an olive gray with shades of brown in transverse bands, and whitish below; this is the largest species described by Duméril and Bibron, the total length being about 11 inches, of which the body is only 3; it is peculiar to Java: 2,

DRAGON

the flying dragon (D. Daudinii, Dum.), from Java, of a grayish color above with black spots, and the wings marbled with the same; total length about 9 inches: 3, the Timor dragon (D. Timorensis, Peron.), with wings spotted with brown on a reddish ground, and a row of ridged scales larger than the rest on each side of the median line of the back; length about 8 inches; probably a variety of the last: 4, the banded dragon (D. quinquefasciatus, Gray), with 5 brown bands traversing the upper surface of wings and back; from the East Indies; about 10 inches long. The dragon of Dussumier (D. Dussumieri, Dum.) has the nostrils opening vertically, the wings spotted with brown near the body and widely marbled with the same on their upper free edge, and a black band across the lower surface of the neck; length about 8 inches; it is a native of the continent of India. The red-bearded dragon (D. hæmatopogon, Boie), from Java, has vertical nostrils, and a large black spot on each side of the red gular pouch; length about 9 inches. There are 2.species which have the tympanum concealed under the skin, constituting the genus dracunculus of Wiegmann; these are the lined dragon (D. lineatus, Daudin) of Amboyna and Celebes, about 6 inches long, with the back ashcolored, and the wings grayish brown with longitudinal white lines; the Philippine dragon (D.spilopterus, Wiegm.), from the neighborhood of Manila, about 8 inches long, with red wings spotted with black or brown, and throat yellow with black dots. Dragons live almost entirely in trees, and feed upon insects, which they catch with dexterity.

DRAGON, an animal often alluded to in the Bible, supposed by some to be the crocodile, and by others to refer, in some passages, to a species of giant serpent, or to a wild beast like the jackal or wolf. According to Robinson's Calmet, it is not improbable that St. John had in mind the enormous boa of Africa and the East when he described the symbolic great red dragon.In mythology, the dragon is a fantastic animal, variously represented as of immense size, with wings, thorny crests, powerful claws, and a snaky tail and motion. He figured in the ancient conceptions of the Orient and of the classical nations, was a familiar subject in the middle ages, is still an emblem of universal use among the Chinese, and seems to have existed almost everywhere except in nature.

DRAGON-FLY (libellula, Linn.), an insect of the family subulicornes of Latreille, and the order neuroptera. The insects of this genus, in this country commonly called "devil's needles," in the perfect form are light and graceful fliers, of the most brilliant and beautiful colors, with 4 large, shining, delicate wings of nearly equal size; the mouth is arranged for crushing insect prey, provided with strong horny mandibles and spiny maxilla; the eyes are lateral, large, and brilliant, with 3 stemmata upon the top of the head; the antennæ consist of from 3 to 6 joints; the legs are short, 6 in number, directed forward,

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599 arising from a firm thorax formed of 3 united segments; the abdomen is very long, a flattened cylinder, soft, without sting or piercer, and in the males terminated by 2 lamellar appendages. In some genera the male sexual organs are placed in the 2d abdominal ring, and those of the female in the last ring, which requires an unusual position in the act of reproduction; the female deposits her eggs on aquatic plants beneath the surface of the water. From their lightness and beauty the French call them demoiselles. Kirby speaks of their "dress" as "silky, brilliant, and variegated, and trimmed with the finest lace;" Mouffet says they "set forth nature's elegancy beyond the expression of art;" yet with all their gay coloring they are among the most voracious and cruel of insects, darting with hawk-like swiftness and ferocity upon gnats, mosquitoes, butterflies, and almost any soft-bodied winged insect, eating even their own species. They are not only in no way injurious to man, attacking neither his person, cattle, nor crops, but are directly beneficial in destroying many noxious insects. They hover over pools in search of prey, or dart from a post or fence upon insects coming near; having caught one, they alight to devour it, first pulling off the wings; in their habits they resemble the fly-catchers among birds. They are equally carnivorous in the larva state, which they pass in the water. The larvæ are without wings; they have 6 feet, and a very complicated arrangement of the parts forming the under lip, which covers the face like a mask, concealing the mouth, and serving by the unfolding of its plates for seizing and conveying food to the mouth; they crawl stealthily along the bottom, like a cat, and when within reach spring their jointed mask upon insects and even small fishes with great precision. By a valvular apparatus at the end of the tail, these larvæ draw in and expel water, using the jet against the surrounding stationary fluid as a means of locomotion; the currents thus produced also bring insects within reach of the jaws, and doubtless serve some of the purposes of respiration, though respiratory trachea also exist on the sides of the body. They remain several months in the water, and change their skins several times. The nymphs have rudimentary wings, and when they are ready to assume their final change, the brilliant eyes of the future fly may be seen through the envelope, which becomes more transparent; they crawl out of the water upon some bank or aquatic plant, where the pupa skin becomes dry and crisp and bursts open on the back; the head and legs of the perfect insect are slowly thrust and drawn out, the wings gradually expand themselves and become smooth, and the body and limbs assume their just proportions. During the drying of the wings the insect bends the body into a crescentic form, that their delicate tissue may not be disturbed by contact with any foreign substance. The anterior nervures of the wings must be very strong, though light, to enable the rapid vibrations of these organs to be performed; their sec

tion, as in the butterfly, would probably present the form found by engineers to be that of the beam of greatest strength and lightness, viz.: the greatest amount of material thrown into the oval flanges, connected by the thinnest possible median support. According to Drury, these insects are 2 years in reaching the perfect form from the egg; after flying about a few weeks, and having performed the act of reproduction, the wings become ragged, the strength fails, and they soon die. They are sometimes seen in immense swarms; M. Poey says that at certain seasons of the year the north winds sweep hosts of them into the neighborhood of Havana; in Belgium in 1854 a swarm was seen extending of a mile, and requiring nearly an hour to pass a given spot, the lowest individuals flying at a height of about 6 feet. The restricted genus libellula, of which nearly 20 species inhabit New England, has a flattened, moderately long body, an almost globular head, the eyes contiguous or approximate, and the wings horizontal when at rest. The larvae are short and thick, of a rough appearance, and a dirty color; they have 5 appendages to the tail. The genus ashna (Fab.) includes the large species, with long slender bodies, which keep the wings expanded when at rest; the larvæ are larger, long and slender, with the abdomen flat below and rounded above; this includes the L. grandis (Linn.), the largest and most predaceous of the British genera; there are about a dozen species in Massachusetts. In the genus agrion (Fab.) the wings are perpendicular during repose, the head transversal, and the eyes far apart; this includes the species with the slender and filiform abdomen, sometimes of extraordinary length; the larvae are small, with round slender bodies terminating in 3 feathery appendages; there are about 10 northern species well known, many of them delicate and beautiful; among the foreign species are some of the most brilliant of insects. Many of the finest American species of this family are described and figured by Drury.

DRAGON'S BLOOD. See BALSAMS. DRAGOONS (Fr. dragons, from Lat. draconarius, a standard bearer), a species of cavalry first introduced by Marshal de Brissac in France in the 16th century, when they were armed with muskets and trained to fight according to circumstances, either as cavalry or infantry. They manœuvred either in or out of the line, extended themselves as skirmishers on the wings, fired upon the enemy, and then deployed behind a column of infantry to reload their pieces, promptly returning again upon their adversaries. They were subsequently of especial service in passing rivers and defiles, and as an escort for the baggage and convoys of artillery. In the 18th century they lost their hybrid character, were generally used as cavalry, and now form in most of the European armies a grade between cuirassiers and hussars, mounted on horses too heavy for the latter and too light for the former. Nicholas of Russia created a dragoon corps of 8 regiments designed to act either as cavalry or in

fantry, but they were reduced to simple cavalry by his successor. The first corps of dragoons in England, called the royal regiment of dragoons of North Britain, was raised in 1681, and is now the Scots greys. There are two regiments of dragoons in the U. S. army. (See also CAVALRY.)

DRAGUIGNAN, a town of France, capital of the department of Var, 41 m. N. E. from Toulon; pop. in 1856, 9,900. It rises in the midst of a fertile valley, surrounded by high hills covered with rich vineyards. It is well built, with several elegant edifices, and numerous fountains. It contains a library of 15,000 volumes, among which are a few very valuable works, a cabinet of medals and of natural history, law courts, a parish church, and a fine clock tower. The inhabitants are employed chiefly in the silk mills and soap works of the environs, and in preparing and selling olive oil. Draguignan is an ancient town; was last fortified in 1615; and its possession was a matter of contention in many of the wars of France.

DRAINAGE, the art of freeing land from superfluous water by causing it to flow off in channels or through porous substances. The system of drainage adopted for cities and towns is commonly described as SEWERAGE, and will be noticed under this head, as that of mines in the article devoted to that subject. (See also PUMP.) The art is of especial interest in its application to the reclaiming of wet lands, and the improvement of those through which the water that falls upon them in rain, or is brought by subterranean channels, does not find a ready exit. The importance of this branch of the art appears to have been appreciated by the ancient Romans, who are known to have constructed open drains for conveying away the superficial water from their lands, and to have laid underground water pipes of earthenware, which some suppose were for the same purpose, but which are with more probability referred by others to the purposes of aqueducts for supplying water to their houses. In England public attention was directed to the injurious effects of water retained in cultivated lands by the treatise of Capt. Walter Blyth in 1652. In this work the tendency of wet lands to produce the flag and rush instead of useful crops was forcibly portrayed, and the remedy of deep drainage as strongly urged. The author condemned the shallow open drains in common use, and recommended straight trenches reaching below the spring of "cold, spewing, moyst water," which he regarded as the source of the "corruption that feeds and nourisheth the rush or flagg," even to the depth of 3 or 4 feet, and the filling in of the trenches with stones, or with faggots covered over with turf. It was long, however, after his time before the excellence of this system was generally recognized, and little attention appears to have been directed to the subject until the latter part of the next century. About the year 1764 a shrewd farmer of Warwickshire, Mr. Elkington, undertook to investigate the peculiar qualities

of one of his fields in which the sheep were badly affected by the rot. He discovered that when an impervious stratum beneath the soil was perforated with an iron bar, the water confined below welled up and flowed away; and he hence inferred that the water in wet lands came chiefly from subterranean sources, and might be removed by tapping the stratum that confined it, and thus letting off the superfluous quantity. On this theory he established an original system of drainage, and was himself remarkably successful in seeking out the sources of the water, the supplies of which, after reaching by an auger, he drew off in a single deep channel dug for the purpose. This system came into extensive practice in England and Scotland, and its imperfections were not fully appreciated till after the introduction of the system of Mr. James Smith of Deanston, first brought forward in 1823. This, which its inventor called frequent or thorough drainage, and others named the Deanston system, was contrived with reference to the removal of the water collected by rains upon the surface, as well as that lying beneath the soil, and was in fact the practice recommended nearly 200 years before by Capt. Blyth. A series of parallel drains were sunk in the direction of most rapid descent, and being partially filled with stones small enough to pass through a 3-inch ring, were covered over with soil. At the bottom a main drain was constructed, of sufficient capacity to convey away all the water from the smaller drains, and this he directed should be made in stone work or with tiles. The new practice met with great opposition from the advocates of the method of Elkington, but finally came to be regarded as the only complete system applicable in all cases. In some instances the other plan may no doubt be economically adopted. The drains came at last to be made chiefly of tiles, for the manufacture of which the first machine was invented by the marquis of Tweeddale. The practice has been successfully introduced into the United States; and in Albany and New York draining tiles are already a considerable branch of manufacture. They are also made in New Jersey, Pennsylvania, and Ohio. Their forms and the manner in which they are used will be described after a few remarks upon the necessity and effects of drainage.-Wet lands are well known to be unfavorable to the production of large crops; it is also true that grains, potatoes, grass, &c., are of sounder and better quality when grown upon lands not subject to excess of moisture. The soils that retain it are correctly described as cold, while the more porous soils of a sandy nature are called warm. The former are chilled by the evaporation continually going on, while the latter are warmed below by the rain water which percolates through from the surface, and are heated by the direct action of the sun's rays. By the experiments of Mr. Parkes in a bog in Lancashire, it appears that by giving free passage to the water through a cold soil by thorough drainage, its temperature at the

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depth of 7 inches may be raised 10° above that of undrained adjoining land of the same quality. Thus drainage produces the effect of a warmer climate, and may add in fact many days to the length of the season; and this not merely by reason of the warmth extended for a longer period, but in the spring the soil is sooner prepared for cultivation, and may be in condition for ploughing and planting even two weeks before neighboring land of similar quality in other respects would admit of the passage of oxen and horses for working. An instance of such a gain in time was reported in 1856 by the secretary of the board of agriculture of the state of Maine. In the late spring of the northern states, where the snow often lies in April, and the ground is saturated with moisture in May, the advantage thus secured is of great importance. While frequent accession of water is a great benefit to lands through which it finds a ready passage, its retention impairs in various ways the fertility of the soil. It prevents the pulverization of the earth by the plough and harrow, and the circulation of air to the roots of the plants. It nourishes a growth of noxious plants, and in woodlands its injurious effect is seen in the production of many lichens, fungi, and other parasites upon the trees. Even the cattle and sheep pastured upon wet lands are subject to diseases from which those in dry fields are comparatively free, and are moreover pestered by swarms of flies and mosquitoes, which disappear as the same lands are drained. Man himself is often the greatest sufferer from undrained lands, which tend to engender fevers and agues; and these are known to prevail long after the forests have been removed, showing that the cause is not so much the decay of large bodies of vegetable matter, as the cold dampness produced by the saturation of the earth with moisture. By the recent researches of Dr. H. I. Bowditch of Boston, it appears that consumption also is more prevalent in those localities in Massachusetts which are badly drained, 50 out of 55 districts in the state of decidedly consumptive character being found wet by contiguity to ponds or marshes, or by reason of low and springy lands. In the vicinity of the wet and unhealthy localities are often found others which appear to be as free from any tendency to induce or aggravate the disease as the distant regions to which patients are sent for recovery. It is a singular fact, fully established by experience, that undrained lands are more liable to suffer from drought than those thoroughly drained. The former in a dry time become baked and compact, and do not readily absorb moisture from the atmosphere; but a well pulverized and open soil receives into its pores and absorbs like a sponge the dew and aqueous vapor in the air. The moisture finds its way to the lower portions of the soil, and is there taken up by the rootlets, which penetrate deep into the loosened materials. Deep or subsoil ploughing is thus seen to be most advantageously employed in connection with underdraining. The same cause which prevents the

penetration of the water also keeps near the surface the fertilizing substances applied as manure; and these exposed to the heat of the sun are in great part dissipated, their richest ammoniacal portions going off in exhalations to be precipitated by the rains upon other lands. Undrained soils in cold climates suffer from another cause. They are liable to freeze when saturated with moisture; and as they thaw, or, in popular language, as the frost comes out of the ground, they are so heaved and broken up, that the roots of the grasses and winter grains are thrown out, and the plants are destroyed; this is what is called winter-killed. By draining and subsoiling, a way is opened for the moisture to sink beyond the reach of frost, and the soil is left too dry to be disturbed by the thaws of spring. From these remarks may be inferred the inutility of mere surface draining. Open trenches may convey away the surface water, but do not reach the cold stagnating repositories beneath the soil, which check that free circulation of fluids which is as essential to the health of vegetable bodies as that of the air to animals. Such ditches should be used only as brooks in the lowest grounds to convey away the water discharged into them by the underground drains coming down the slopes. Deep ditches partially filled with small stones or with brush, or laid at bottom with flat stones, are found by long experience to be not so well adapted to accomplish the object sought for as drains laid with tiles. These are short pipes moulded and baked of brick clay. Some are of cylindrical shape; and in others, called the horse-shoe tile, the section is an incomplete circle, and when laid the tiles are placed upon the 2 edges, either directly upon the ground, or separated from it by the intervention of flat pieces of the same material, placed so as to break joints with the tiles. In another form which is very generally used, called the sole tile, the flat bottom piece, instead of being separate, is a part of the tile itself, and is the foot upon which it stands. This and the pipe tile are considered far superior to the horse-shoe. Tiles are made of various sizes from 2 to 8 inches diameter, moulded by machines in lengths of about a foot, and baked as thoroughly as common hard-burned bricks. They are carefully set in the ground end to end; but the cylindrical pipes are often furnished with a collar which slips over and holds 2 adjoining ends. The bottom of the trench is dug with excavating tools, made for the purpose, just wide enough to admit the tiles. The water filtering through the soil passes into the pipes by the numerous joints, entering chiefly at the bottom, and the multiplication of these joints is the chief object of the short lengths. Tiles should always be imbedded in compact soil, and at a depth somewhat dependent upon the contour of the ground as well as other circumstances. A sufficient slope must be secured for the water to flow readily through the drains. There should be no interruptions to the descent,

causing depressions in which sediment might accumulate to obstruct the drainage. The least fall admitted by most authorities in the usual sized drains is not less than 1 in 600 or 700; but so gentle a slope is rarely advisable; indeed, not less than 1 in 200. The depth generally agreed upon as the best is at least 4 feet. The tiles are at this depth rarely reached by a hard frost, and are not disturbed by the pressure of the subsoil plough, which penetrates a few inches over 2 feet below the surface. This depth is also lower than the roots of most of the crops are likely to extend; but the tiles cannot be placed beyond the possibility of injury from the roots of willows, poplars, and other trees which strike down in an open soil to uncertain depths. Their distance apart should depend upon the nature of the soil. In compact clays they have been set within 15 feet of each other; but this is unnecessarily close. If the subsoil be clayey, it is not well to exceed 30 feet; for if the drains once laid are found to be ineffectual, as they have in many instances proved, the only expedient is to make an additional one between each 2 of the original set. If the subsoil is very porous, the tiles may be placed 40 feet apart; but if trials at a greater distance than this are ever found effectual, it is believed their success should be referred to the principle of Elkington, the drains tapping a porous stratum containing water which was kept from flowing by an impervious overlying stratum. The effect of drains is not always perceived immediately after heavy rains. Some time is required for a dry soil to become saturated, and the moisture is then gradually given off below. The plants thus have sufficient opportunity to obtain the benefit of the water which passes through, and no danger is incurred of overdrainage, especially as the lands are left in better condition, as already stated, for absorbing atmospheric vapor. In stiff clayey soils the operation, though it would at first appear impracticable, is greatly facilitated by the property of the clays to shrink and open in cracks in passing from a wet to a dry state. This process commences near the drains, and the cracks extend back, serving as they open as minor channels for leading the water down to the tile beds. They have been traced stretching across through the clay with innumerable ramifications nearly from one drain to the next; and though they close again when very wet, they still let water pass along their lines.The most extensive agricultural drainage operations in the United States are on the farm of Mr. John Johnston, near Geneva, N. Y. By steadily pursuing the practice for about 20 years, he has accomplished the laying of 210,000 tiles, or over 47 m. An instance of their beneficial effect was observed a few years since, when by the destructive action of the midge the crop of wheat upon 6 adjoining farms was reduced to 7 bushels per acre, while he obtained 29 bushels. The system of drainage adopted in the central park of New York city, under the direction of George E. Waring, Esq., is very complete, and