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subsided. The plate, polished and cleansed with whiting, is then placed to receive the liquid, which being poured on it, is held slanting till the most fluid parts have run off; it is afterwards laid to dry, in the progress of which the resin granulates, and adheres firmly to the surface. The greatest precaution must be used in going through this process, as the interposition of dust, grease, hairs, or fibres of linen, will cause total derangement; and even then it is subject to most vexatious uncertainty, often compelling the experienced artist to renew it to obtain a good grain; in short, the weather and untoward accidents frequently ruin his labours, though guarded against by every method his invention suggests. There is one advantage attending the pouring the liquid off, which is, that the heaviest particles of the resin will float to the lower side, and consequeutly leave a coarser grain there than above, much better suited to the deep shades of a landscape than if the granulations had been equally fine ; in large subjects the grain is sometimes laid coarse purposely in the parts requiring it. Although a fine grain has a very pleasing effect, and will bear close examination, it has several disadvantages; for this reason a medium description of granulation is preferable, which, admitting the aqua fortis freely to the copper, it bites deeper, and is less apt by acting laterally to force off the resin; besides, the plate will of course afford a greater number of impressions. Some hints have been given already for biting the plate; but however useful those may be found in particular instances, there are others which can only be extracted from close application and experiment, and those are often varied in their results: as an illustration, we may suppose an artist provided with several picces of copper granulated, and trying each successively by his watch with spirits of nitre diluted to the state of the air at the commencement of his operations, how many minutes are necessary to produce one tint, how many for a second, &c. granting him two hours for his experiment; during this interval a violent shower of rain may occur, which will immediately affect the acid, by weakening its properties in the same proportion as salt is observed to be dissolved by a humid atmosphere : thus it appears, a result obtained on a clear dry day will not suit a rainy one, and vice versa. In opposition to this discouraging un
certainty, and in opposition to the judgment and preference of all true connoisseurs, aquatinted prints seem to increase in value in the estimation of many persons, who forget that national taste should be improved by works of superior execution, and not vitiated by being constantly familiarized to those produced by means which set genius at defiance. ENN EAGON, in geometry, a polygon with nine sides. If each side be 1, the area will be 6, 18. Soc. ENNEAN DRIA, the name of the ninth class in Linnaeus's sexual system, consisting of plants which have hermaphrodite flowers, with nine stamina or male organs. The orders, or secondary divisions in this class, are three, being founded on the number of the styles, seed buds, or female organs. Laurus, tinus, and cassytha, have one style; rhubarb, (rheum,) has a triple stigma or summit, but scarce any style; flowering rush has six styles. The genera just enumerated are all that belong to the class Enneandria. The first genus, laurus, is very extensive; comprehending the bay tree, cinnamon tree, camphor tree, benjamin tree, sassafras tree, and the avocado or avogato pear. ENS martis, an old name given by chemists to sal anamoniac sublimed with iron filings, and therefore consisting of muriate of ammonia mixed with a little muriate of iron. ENs veneris, a similar preparation, in which copper filings are substituted for those of iron. ENSATAE, (from enses, a sword.) the name of the sixth order in Linnaeus's Fragments of a Natural Method, consisting of plants with sword-shaped leaves. ENSIFORM, in general, something resembling a sword, ensis : thus we find mention of ensiform leaves, ensiform cartilage, &c. ENSIGN, in the military art, a banner under which the soldiers are ranged, according to the different companies or places they belong to. The European ensigns are pieces of taffety with various figures, arms, and devices, painted on them in different colours: the Turkish ensigns are horses’ tails. ENstg N is also the officer that carries the colours, being the lowest commissioned officer in a company of foot, subordinate to the captain and lieutenant. It is a very honourable and proper post for a young gentleman on his first coming into the army; he is to carry the colours,
both in assault, day of battle, &c. and should not quit them but with his life; he is always to carry them himself on his left shoulder, only on a march he may have them carried by a soldier. If the ensign is killed, then the captain is to carry the colours in his stead. ENTABLATURE, in architecture, is that part of an order which rests on the capital of a column, and comprehends the architrave, frieze and cornice. ENTAIL, in law, signifies fee-tail, or fee intailed. See ESTATE. ENTIERTIE denotes the whole, in contradistinction to moiety, which denotes the half; and a bond, damages, &c. are said to be entire, when they cannot be apportioned. ENTIRE tenancy, signifies a sole posSession in one inan. ENTOMOLOGY is that branch of natural history that treats of insects. The study of insects has sometimes been ridiculed as unworthy the attention of men of science ; for this, however, there is no just reason; though inferior in point of magnitude, yet they surpass, in variety of structure and singularity of appearance, all the larger branches of the animal world. No one can examine with an attentive eye the subjects of this branch of science without surprise; the great variety of forms, the nice adaptation of their parts to the situation in which each happens to be placed, may excite the amazement of the curious and intelligent mind The same power and wisdom which are manifested in the order, harmony, and beauty of the heavenly bodies, are equally shown in the formation of the minutest insect; each has received that mechanism of body, those peculiar instincts, and is made to undergo those different changes, which fit it for its destined situation, and enable it to perform its proper functions. The utility of many insects, either in their living or dead state, as the bee, the crab, the silk-worm, cochineal insect, (see APIs, Coccus, &c.) renders them interesting and important; besides, tho’ diminutive in point of size, they are, in regard to numbers, unquestionably the most distinguished of the works of nature; they are to be found in every situation, in water, in air, and in the bowels of the earth; they live in wood, upon animals, decayed vegetables, and all kinds of flesh, and in every state of its existence down to the most putrid. The general characters by which in*cts are distinguished are the following: they are furnished with six or more feet; WOL. V.
the muscles are affixed to the internal surface of the skin, which is a substance more or less strong, and sometimes very hard and horny; they do not breathe like larger animals, by lungs or gills situated in the upper part of the body; but by a sort of spiracles distributed in a series or row on each side the whole length of the abdomen; these are supposed to communicate with a continued chain, as it were, of lungs, or something analogous to them, distributed throughout the whole length of the body; the head is furnished with a F. of what are termed antennae, or horns, which are extremely different in different tribes, and which by their structure, &c. form a leading character in the institution of the genera into which insects are divided. Writers on natural history formerly included snails, worms, and the smaller animals, or animalcules, in general, among insects: these are now more properly placed among the tribe vermes, or wormlike animals. Late writers have extended this still further, and have very properly excluded almost the entire Linnaean order of Aptera, forming of it a distinct class, under the name of Crustacea. Insects have also been denominated bloodless animals, which modern discoveries have shewn to be contrary to fact : their blood is o a colourless sanies. Some of them, as the cimex lectularius,
have been frequently used, with the mi
croscope, to exhibit in a striking manner the circulation of the blood. In this insect, with a good glass, the vibrations and contractions of the arteries may be distinctly observed. Most insects are oviparous; of course, the first state in which insects appear is that of an ovum or egg. This relates to the generality of insects, for there are some examples of viviparous insects, as in the genera Aphis, Musca, &c. From the egg is hatched the insect in its second or caterpillar state; this second state has been usually known by the name of eruca, but Linnaeus has changed it to that of Lanva, which see; considering it as a sort of masked form, or disguise, of the insect in its complete state. The larvae of insects differ very much from each other, according to the several tribes to which they belong; those of the butterfly and moth tribe (phalaena) are generally known by the name of caterpillars; those of the beetle o except such as inhabit the water, are of a thick, clumsy form. The larvae of the locust, or grasshopper, (gryllus,) do not differ very F.
much in appearance from the complete insect, except being without wings. The larvae of flies, bees, (musca, apis,) &c. are generally known by the name of inaggots, and are of thick short form. Those of water beetles (dytiscus) are of highly singular forms, and differ, perhaps, more from that of the complete insect than any others, except those of the butterfly tribe. Some insects undergo no change of shape, but are hatched from the egg complete in all their parts, and they undergo no farther alteration than that of casting their skin from time to time, till they acquire the complete resemblance of the arent animal. In the larvae state most inst cts are peculiarly voracious, as in many of the common caterpillars. In their perfect state some insects, as butterflies, are satisfied with the lightest nutriment, while others devour animal and vegetable substances with a considerable degree of avidity. When the larva is about to change into the crysalis or pupa state, it ceases to feed, and having placed itself in some quiet situation, lies still for several hours, and then, by a sort of effort, it divests itself of its external skin, and immediately appears in the different form of a chrysalis or pupa : in this state, likewise, the insects of different genera difier almost as much as the larva. In most of the beetle tribe it is furnished with short legs, capable of some degree of motion, though very rarely exerted. terfly tribe it is destitute of legs; but in the locust tribe it differs very little from the perfect insect, except in not having the wings complete. In most of the fly tribe it is perfectly oval, without any apparent motion or distinction of parts. The pupa of the bee is not so shapeless as that of flies, exhibiting the faint appearance of limbs. Those of the dragon-fly (libellula) differ most widely from the appearance of the complete insect; from the pupa emerges the insect in its ultimate form, from, which it never changes, nor receives any farther increase of growth. Different naturalists have attempted to arrange insects into families and genera, particularly the celebrated Linnaeus, whose arrangement may be thus explained. He has formed them into seven families or orders, composing his sixth class of animals, Insecta: he defines an insect, a small animal, breathing through ores on its sides, furnished with movea§. antennae and many feet, covered with either a hard crust or a hairy skin. As introductory to the distinguishing marks of the orders and genera, it will be ne
In the but- .
cessary to enumerate and explain the terms given to the different parts, and the most remarkable of the epithets applied to them by entomologists. The body is divided into head, trunk, abdomen, and extremities. 1. Caput, the head, is in insects, as well as in the vertebral animals, the principal repository of the senses, and contains that most important organ, the brain: externally it is furnished with eyes; stem. mata ; antenna: ; clypeus; vertex; mouth; front ; gula. Eyes, are situated on each side of the head, and difier much in form and colour in the different insects, and may be considered amongst the most surprising of nature's works; they are not, as might be at first supposed, mere hemispherical bodies of plane and simple surfaces, but examination proves them to be composed of an immense assemblage of highly wrought hexagonal fascets, each furnished with its proper optic nerve, retina, &c. complete for vision : the number of these fascets difiers in different species; in the eye of the common fly 8,000 have been counted, and in that of the libellula or dragon fly about 12,000. Stemmata are hemispherical bodies placed upon the vertex, and are supposed to perform the office of eyes. The antennae are two articulated moveable processes, placed on the head; they are either, 1. Setacea, setaceous, i.e. like a bristle, when they taper gradually from their base to their point. 2. Clavatae, clawated, i.e. club-shaped, when they grow gradually thicker from their base to their point. 3. Filiformes, filiform, i.e. threadshaped, when they are of an equal thickness throughout the whole of their length. 4. Moniliformes, moniliform, i.e. of the form of a necklace, when they are of an equal thickness throughout, but formed of a series of knobs, resembling a string of beads. 5. Capitatae, capitate, when they grow thicker towards the point, and terminate in a knob or head. 6. Fissiles, fissile, i.e. cleft, when they are capitate, and have the head or knob divided longitudinally into three or four parts or laninae. 7. Perfoliatae, perfoliated, when the head or knob is divided horizontally. 8. Pectinatae, pectinated, i.e. resemblin a comb, when they have a longitudin series of hairs projecting from them, in form of a comb. 9. Barbatae, barbed, when they have little projections or barbs laced on their sides: they are either ongiores, longer than the body; breviores, shorter than the body : or, me: diocres, of the same length with the bod Cuvier has shewn that the organs of hearing are placed at the base of the antennae in the crustacea, such as crabs and lobsters, and from analogy many naturalists have supposed them to be similarly situated in the true insects; this may probably be correct, but it has not ret been proved, and must not therefore e assumed. Clypeus, the covering of the head in the beetle tribe; it extends from the eyes, often projecting over the mouth. Vertex, the top of the head above the front. Front, this term is applied to the anterior part of the head of most insects, and is analogous to the clypeus of the beetles. Gula, throat, underneath the head, supporting the lip. Mouth, is situated in the head, rarely in the breast, and affords so great a variety of characters, that the celebrated Fabricius founded upon them his entire system of arrangement; the principal and most obvious parts are, the palpii, mandibulae, labrum, labium, ligula, maxillae, and galeae. Palpi, or feelers, are articulated filaments of different forms, sometimes resembling antennae, placed in the mouth, either on the jaws or lip; they are two, or four, or six, in number, and are either anterior, intermediate, or posterior, or, according to Latreille, labial or maxillary. Considered in relation to those parts upon which they are situated, they generally furnish good generic characters. Mandibulae, mandibles, two horny curved pieces, placed one on each side of the mouth, moving laterally, and used by the insect either to seize its food, or as weapons in its combats. Maxillae, jaws, two horny or submembranaceous pieces, placed one under each mandible, generally ciliated with hair, or dentate on the inner side, and always palpigerous in those insects that have more than one pair of palpi. Labrum, or as it is sometimes termed labium superius, upper lip, a transverse moveable piece, F. immediately below or underneath the clypeus and above the mandibles. Labium, lip, termed by some entymologists labium inferius, and by others mentum, or chin, a horny substance, sometimes truncate, and terminates the mouth; beneath it supports the posterior palpi, and serves as a sheath for the tongue.
Ligula, a soft instrument, coriaceous at the base, often bifid at the tip, and retractile; this part is found only in insects provided with mandibles. Galae, casque, two membranaceous, inarticulate pieces, placed one on each side of the mouth in some insects of the hemiptera and neuroptera orders, and in conjunction with the lips covering the mouth ; this part is by some considered as an anterior palpi, or an exterior division of the jaws. In some insects the mouth is elongated into a tube, or placed at the end of a projection of the head, and is then either a lingua, proboscis, haustellum, rostellum, Ol' rostrum. Lingua, tongue, soft, flexible, tubular, involuted, like the spring of a watch, usually obtuse at its termination, and placed under the head between the palpi of the butterflies and moths. Proboscis, trunk, soft, retractile, inarticulate, labiated at the extremity, and is peculiar to the flies; the common fly af. for is a good example of it. Haustellum, sucker, composed of very fine and rigid filaments, enclosed in a bivalve sheath, and is peculiar to the cinices, and some of the flies. Rostellum, a bill, or beak, coriaceous, articulate, and inclosing the haustellum. Rostrum, a prolongation of the head, terminated by the mouth, as in the cur. culios, &c. Some of these terms are not used by some authors as here defined ; and indeed so unsettled are many entomological terms, that the student is often very much perplexed by the various applications of them. II. Truncus, the trunk, to which the legs are attached, is situated between the head and the abdomen; it is divided into, 1. The thorax, or chest, which is the superior part. 2. Scutellum, i. e. small shield or escutcheon, separated from it by a suture, on the posterior part. 3. The breast and sternum, which is the inferior part. III. The abdomen, that part which contains the stomach, intestines, and other viscera, consists of several annular segments; it is perforated on the sides with spiracula, or breathing-holes; the upper art of it is termed tergum, or back; the inferior part venter, or belly; the posterior part anus.
IV. Artus, the extremities, are the wings, legs, and tail.
(1.) Alae, the wings, are two or four; they are either, 1. Planae, i. e. plain, such
as cannot be folded up by the insect: or, 2. Plicatiles, or folding, such as can be folded up by the insect at pleasure. , 3. Erectae, erect, such as have their superior surfaces brought into contact, and stand upright when the insect is at rest. 4. Patentes, spreading ; such as are extended horizontally. 5. Incumbentes, incumbent; such as rest on the upper part of the abdomen 6. Deflexa, bent down ; such as are partly incumbent, but have their exterior edge inclined towards the sides of the abdomen 7. Reversae, reversed; such as are incumbent, but inverted. 8. Dentata, such as have their edges notched or serrated. 9. Caudatae, such as have processes extended from their extremities like a tail. 10 Reticulatae, netted; when the vessels of the wings put on the appearance of net-work. 11. Pictæ, painted ; such as are marked with coloured spots, bands, streaks, lines, or dots. 12. Notatae, marked with specks. 13. Ornatae, adorned with little eyes, or circular spots, containing a spot of a dif. ferent colour in their centre : the central spot is termed pupil; the exterior one is called iris; this may happen either in the primary or secondary wings, on their uper or under surfaces: the superior wing is called primary, and the inferior secondary, to avoid confusion, as they may be at times reversed. The elytra are hard shells, occupying the place of the upper wings. They are for the most part moveable, and are either, 1. Truncata, truncated, when shorter than the abdomen, and terminated by a transverse line, 2. Spinosa, or prickly, when their surfaces are covered with sharp points or prickles. 3. Serrata, serrated, when their edges are notched. 4. Scabra, rough, when their surface resembles a file. 5. Striata, striated, when marked with slender longitudinal furrows. 6. Porcata, ridged, when marked with elevated ridges. 7. Sulcata, furrowed. 8. Punctata, marked with dots. 9. Fastigiata, when formed like the roof of a house. The hemelytra, as it were half-elytra, partaking partly of the nature of crustaceous shells, and membranaceous wings, being formed of an intermediate substance. Halteres, or poisers, are small orbicular bodies placed on stalks, situated under the wings of insects, of the order Diptera. (11.) Pedes, the legs, are divided into, 1. Femur, or thigh, that part which is joined to the trunk. 2. Tibia, or shank. 3. Tarsus, or foot. 4. Ungues, hooks or nails. 5. Manus, (chela,) hands or claws, simple, with a moveable thumb, as in the crab. The hind legs are termed, 1.
Cursorii, formed for running. 2. Saltatorii, formed for leaping 3. Natatorii, formed for swimming.
(Ill.) Cauda, the tail, which terminates the abdomen, is 1. Solitaria, i. e. single. 2. Bicornis, i. e. two-horned, or double. 3. Simplex, simple, i. e. unarmed. 4. Armata, i. e. furnished: 1. with forceps or pincers: 2, with furca, a fork: 3. with one or more setae, or bristles: 4 with an aculeus, or sting, either smooth or barbed. A sting is a weapon frequently hollow, with which some insects are furnished, and through which they discharge a poison into the wound they inflict.
The sexes of insects are commonly two, male and female. Neuters are to be met with among those insects which live in swarms, such as ants, bees, &c.
The majority of insects are observed to be annual, finishing the whole term of their lives in the space of a year or less, and many do not live half that time; nay, there are some which do not survive many hours; but this latter period is to be understood only of the animals when in their complete or ultimate form. for the larvae of such as are of this short duration have in reality lived a very long time under water, of which they are natives; and it is observed, that water insects, in general, are of longer duration than land insects. Some few insects, however, in their complete state, are supposed to live a considerable time, as bees for instance ; and it is well known that some of the butterfly tribe, though the major part perish before winter, will yet survive that season in a state of torpidity, and again appear and fly abroad in the succeeding spring; spiders are also thought to live a considerable time, and some species of the genus cancer are said to live several years, especially the common lobster, &c.; it should be observed, however, that these animsls, in the opinion of some modern naturalists, constitute a different tribe of beings from insects properly so called. Linnaeus has divided insects into seven orders. 1. Co. LEoPTERA ; II. HEMIPTERA; III. LEPI popTERA ; IV. Nsu hopTERA; V. HYM Exop. TERA; VI. Di PTERA ; VII. APTERA, which see : and from these the several genera are referred to.
ENTRY, in law, is the taking possession of lands or tenements, where the party has a title of entry, or an immediate right to possess them. This may be in person, or by attorney, or is an entry in law, which is merely the making con