MER 4 



r<r, which occurs in Hungary, Sweden, 

 Spain, and some other places ; (3.) In 

 combination with sulphur forming cin- 

 iiabar ; (4., Combined with chlorine, 

 forming horn-me-cury. It is obtained 

 from its ores by distillation. Mercury 

 is used in barometers and thermometers, 

 and very extensively in medicine, in the 

 forms of blue pill, calomel, and corrosive 

 sublimate. It is also used as a pigment in 

 vermilion. 3. In astronomy, the small- 

 est of the primary planets, and the near- 

 est to the sun, for which reason, though 

 it emits a bright light, it is seldom seen. 

 Diameter 3180 miles ; distance from the 

 sun, 36,841,468 miles; sidereal revolution, 

 "* days, 23 hours, 15', 44"; rotation on its 

 txis, Id. Oh. 5', 28'3". Light compared 

 with that at the earth about 7 times. 

 Character ^ . Named from its appa- 

 rent quick motions, after Mercury, the 



messenger of the gods. 1. In botany. 



See MERCURIALIS. 



MEK'CY-SEAT. In scripture antiquities, 

 the propitiatory : a covering of the ark 

 of the covenant. It was of gold, and its 

 ends were fixed to two cherubim, whose 

 wings extended forward, and formed a 

 kind of throne for the Almighty. 



MEK'GEU, from mergo, to merge. A 

 term in law for the merging or drown- 

 ing of a less estate in a greater 



MER'OCS, a diver. The Latin name of 

 some aquatic bird : applied by Linnxus 

 us the generic name of the goosander, and 

 by Brisson as the generic name of the 

 diver, of which Illiger forms the genus 

 Endytes (q. v.). The genus Mergus, Lin., 

 comprehends all those palmipedes of the 

 Lamellirostrine family, in which the bill 

 is thinner and more cylindrical than that 

 of the ducks ; armed along its edges with 

 t-mall pointed teeth, like those of a saw, 

 and having the upper mandible hooked. 

 They live on lakes and ponds, where they 

 are very destructive to fish. The goosan- 

 der (SI. merganser, Lin.), is well known. 



MERiu'iAN.from meridies for medidies, 



mid-day; noon. 2. In astronomy and 



geography, a great circle supposed to pass 

 through the poles, /enith, and nadir, of 

 any given place, intersecting the equi- 

 noctial and equator at right angles. 

 Every place has its meridian, and when 

 tbe sun arrives at this circle, it is noon or 

 mid-day, whence the name. The first 

 meridian is that from which longitudes 

 are reckoned. The choice is entirely ar- 

 bitrary. In British works the longitude 



is reckoned from Greenwich. 3. The 



meridian of a glebe is the brazen circle in 

 which it turns, and by which it is sup- 

 ported Tht matin f tic meridian is a great 

 circle paw.t? through the magnetic poles. 

 The mer:dutn altitude of a heavenly bod7, 

 U iU altitude * tii 2 on the meridian. The 



2 . MES 



meridian line, (I.) On a dial, is Die MIU>* 

 as the 12 o'clock hour line; ;2.i On Gun- 

 ter's scale a line divided unequally 

 towards 87, corresponding to the meri- 

 dian in Mercator's chart. 



MEKID'IOXAL. In navigation. (1.) By 

 meridional distance is meant the distance 

 between the meridians of two places : 

 otherwise called departure (q. v. . 2. 

 Meridional parta, are the parts of the 

 increased meridians, according to Mer- 

 cator's chart, which increase in propor- 

 tion to the cosines of the latitudes to 

 radius, or simply as the secants, the ra- 

 dius being constant. 



MERI'NO. The Spanish sheep: a va- 

 riety remarkable for the fineness of their 

 fleece. 



MERI'ONES. A genus of rodent mamma- 

 lia, separated from the Gerbils by F. Cu- 

 vier. The most known species is the 

 jumping mouse (Jl/iw canaaeHsis, Penn.i 

 of North America. It much resembles 

 our mouse, but its colour is lighter, and 

 it is more active in summer, and spends 

 the winter in a state of lethargy, shut up 

 in its burrow. 



MER'LIN (French). A species of hawk. 

 It is the smallest bird of the hawk-tribe. 



MERLON (French). That part of a pa- 

 rapet which lies between two embra- 

 sures. 



MER'MAID. Maid of the Sea. A fabu- 

 lous creature, described as having the 

 head and body of a woman with the tail 

 of a fish. Some doubted the existence of 

 mermen, who thoroughly believed in the 

 existence of mermaids ! The prototype 

 of the fables about mermaids is the ~Du- 

 gongfa.v.}. 



ME'ROPS. The name given by Linna?us 

 to a genus of passerine birds the Bee- 

 eaters, of the Tenuirostrine family. Their 

 flight is similar to that of the swallows ; 

 and they pursue insects in great flocks, 

 but especially bees and wasps ; by which 

 they are never stung. Name 

 from pi^iti and jty 



ME'ROS (Gr.). In architecture, the plane 

 face between the channels in the tri- 

 glyphs of the Doric order. 



MESEMBR VAX 'THEM UM. fig-marigold. 

 A genus of plants, of which 228 species 

 are enumerated by Don : class Icosandria : 

 order 1'entagynia. Name from /Mtref, 

 middle, ifjt&quo, embryo, and avtios, a 

 flower. The species are all natives of 

 warm climates, and mostly of the C. G. 

 Hope. 



MES'EXTERY, from /u.tirof, middle, and 

 Evrf;a. an intestine. A membrane placed 

 in the middle of the intestines, and to 

 which they are attached, to prevent them 

 from becoming entangled with each other 

 by convolutions. It is formed by a du- 



