372 EARWIG ing the tube and applying the mouth, turned forward and given an elliptical form, close
- iL, r ;fmst the ear. Another modification was a
flat tube passing over the head and applied to each ear, while in front and immediately over the forehead was an opening to receive the sound. One inventor, having observed that in listening intently people opened their mouths, contrived a sort of plectrum or vibrating body to be held between the teeth, and thus to con- vey sounds by the Eustachian tube. After the introduction of caoutchouc and gutta percha into the arts, a long tube of one or other of these materials, with a bell-shaped trumpet at the end, took the place of the metallic trumpet, and for many purposes is very convenient. In England in some of the churches pews are con- structed with tubes to conduct the sound, open- ing in convenient positions for the ear of the listener. Among the more recent inventions for facilitating hearing are the auricle, a small tube of silver with a semi-globular expansion, intended to be inserted into the meatus of the ear ; and the tympanum, a small thin disk of rubber, having a silver wire passing through it to transmit the sound wave. In a few cases the latter has been of considerable service. In total deafness such means are of no advantage. EARWIG, an orthopterous insect, of the fam- ily cursoria or runners, which also includes the cockroach ; it belongs to the genus forfi- cula (Linn.). All the six feet are formed for running ; the wings are four, the upper pair very short, coriaceous like the elytra of co- leoptera, without veins, enclosing the under wings, which are folded both longitudinally and transversely ; the mouth is formed for mastication ; the body is long and somewhat flattened, and armed at the hinder end with a pair of curved blades shutting like scissors or nippers ; there are three joints to the tarsus ; the antennsa are filiform. These insects under- go a partial metamorphosis. They seem to form the connecting link between coleoptera and orthoptera, resembling the former in their elytra, and the latter in the shape of the wings and mouth, and the metamorphosis ; for these reasons most English entomologists adopt for them the order dermaptera of Mr. Kirby and Dr. Leach, considering them coleoptera with . 1. Forflcula. 2. Lithobius. the metamorphosis and caudal appendages of orthoptera. They are common in moist earth, under stones, in decayed wood, and in similar damp and dark places ; they are considered in Europe injurious to peaches, pears, apples, to EASEMENT greenhouse plants, and to pinks, dahlias, and other favorites of the flower garden. The full-grown insect, including its caudal forceps, is not quite an inch long, and its width is one sixth of an inch ; the color is light brown. Being nocturnal, they creep in the daytime into any crevice or hole, and this has given rise to the popular belief that they enter the human ear ; they might attempt this, but the waxy bitter secretion of the ear would proba- bly prevent their entrance ; there are no well authenticated instances of their doing this, and no harm could result if they did, as the drum of the ear would arrest them, and a drop or two of oil would soon destroy them by stop- ping up their respiratory trachea). The com- mon way of catching them in England is by hanging up any convenient vessel or tube for them to crawl into in the morning, from which they are shaken and killed. In the larvae there are no wings or elytra, but the skin is changed several times ; the nymph differs little from the perfect insect; in both these conditions they are voracious, even devouring each other. In this country there are several species, rather uncommon, and never injurious to ve- getation. The many-footed creeping animal erroneously called earwig in America (genus liihobiw) is not an insect, but a myriapodous crustacean, equally innocent of entering the human ear. EASDALE, or Eisdale, an island on the W. coast of Argyleshire, Scotland, in the frith of Lorn, nearly adjoining the island of Seil, about m. long and of nearly the same width, noted for its slate quarries, which have been worked for nearly two centuries, and furnish annually more than 4,000,000 slates. The island consists entirely of slate, and has been so much cut away that a large part of it is now even with or below the level of the sea. EASEMENT, a privilege which the owner of one tenement, called the dominant tenement, has in respect to another, called the servient tenement, by which he may require the owner of the latter to permit something to be done thereon, or to refrain from doing something, which otherwise as owner he would be enti- tled to do. It must be defined and limited in extent, and it must in some way be for the benefit of the dominant tenement, and not for some general benefit to the owner. Among the principal easements are rights of way, the right to carry water or to obtain light or air over the adjoining lands, the right to support of land or buildings by adjacent land or buildings, the right to have party walls and fences kept in repair, &c. In general, they must be created by deed or established by prescription, though every man has a natural right to the support of his land by the adjacent land of another, but not to the support of the artificial struc- tures he may rear upon the land. Easements are lost by release, by abandonment, or by the dominant and servient tenements becoming united in the same ownership. Public rights
