EEC 



[381 ] 



B E F 



posterior to the introduction of 

 man is called recent. 



EE'CENT PE'RIOD. That period of 

 time commencing with the intro- 

 duction of man upon this earth. 



BECE'PTACLE. (receptaculum, Lat.) In 

 botany, the basis or point, upon 

 which all the parts of the fructifica- 

 tion rest. The receptacle is distin- 

 guished into receptaculum proprium, 

 or receptacle appertaining to one 

 fructification only; and receptaculum 

 commune, or common receptacle, 

 connecting several distinct fructifi- 

 cations. 



BECLI'NED. In botany, applied to 

 leaves when the point is lower 

 than the base ; also to stems when 

 curved towards the ground. 



BED CO'RAL. A branched zoophyte, 

 somewhat resembling in miniature 

 a tree deprived of its leaves and 

 twigs. It seldom exceeds one foot 

 in height, and is attached to the 

 rocks by a broad expansion or base. 

 It consists of a bright red, stony 

 axis, invested with a fleshy, or 

 gelatinous substance of a pale blue 

 colour, which is studded over with 

 stellular polypi. 



BED CRAG. The Crag of Suffolk con- 

 sists of two groups, the Bed Crag 

 and the Coralline Crag. The Bed 

 Crag, which is the later formation, 

 is composed of red quartzose sand, 

 and accumulations of rolled shells. 



BED MARL. Another name for the 

 new red sandstone, 



BED OR VARIEGATED MARLS. The 



uppermost division of the red 

 sandstone group. The Marnes 

 Irisees of the French, the Keuper, 

 Bunte Mergel of the German geol- 

 ogists. 



BED SNOW. See Protococcus Nivalis. 



BE'DDLE. The roethel of Werner; 

 the crayon rouge of Brochant ; the 

 argile ocreuse rouge graphique of 

 Haiiy. Bed chalk; a species of 

 argillaceous iron-stone ore. The 

 best specimens are brought from 

 Germany. It occurs in opaque 



masses, having a compact texture. 

 In hardness, it differs but little 

 from chalk. It is dry, and rough 

 to the touch, adhering to the tongue, 

 and yielding an argillaceous odour. 

 Specific gravity from 3-10 to 3 1 90. 



BED SANDSTONE GROUP. This group 

 is placed below the oolitic group, 

 and above the carboniferous group ; 

 and in Sir H. De la Beche's table 

 constitutes the sixth group of the 

 superior stratified or fossiliferous 

 rocks. The red sandstone group 

 comprises 1. The variegated or 

 red marl; 2. The muschelkalk ; 

 3. The red sandstone ; 4. The 

 zechstein or magnesian limestone ; 

 5. The red conglomerate. 



BEEF, (riff, Germ.) A range of 

 rocks lying generally near the 

 surface of the water. 



BEFLEC'TING GONIO'METER. An in- 

 strument invented by Wollaston, 

 and improved by Sang, for mea- 

 suring the angles of crystals. 

 By the reflecting goniometer the 

 smallest crystals may be accurately 

 measured, for, provided the surface 

 be perfect and brilliant, the 100th 

 part of an inch in length and 

 breadth will suffice. 



BEFLE'CTION. The act of throwing 

 back; the act of bending back; 

 that which is reflected. By the 

 laws of optics, the angle of reflection 

 is equal to that of incidence, what- 

 ever the reflecting surface may be, 

 and however obliquely the light 

 may fall upon it. 



BEFRA'CTION. (refraction, Fr. refra- 

 zi6ne, It.) The incurvation, or 

 change of determination in the 

 body moved, which happens to it 

 whilst it enters or penetrates any 

 medium ; in dioptricks, it is the 

 variation of a ray of light from that 

 right line, which it would have 

 passed on in, had not the density 

 of the medium turned it aside. 

 "When light passes through a drop 

 of water or a piece of glass, it 

 obviously suffers some change in 



