MED 



MED 



chuck-rib, brisket, and leg of-mutton 

 piece, 5d. ; the clod and sticking, and 

 neck, 3(/. ; and the legs and shins, 2d. 

 a pound. Such is the difference in 

 value of the different cuts of an ox 

 in the meat markets in London. 



" It is well to observe that the 

 greatest attention should be paid to 

 making the brine or pickle, whether 

 for beef or pork. Pure water should 

 be used in its manufacture ; for the 

 sediment from that which is impure 

 will settle down upon the meat, and 

 give it a bad colour and a slimy feel. 

 Whether river or rain water is used 

 (and soft water should always be pre- 

 ferred), it would be exceedingly desi- 

 rable to filter it through sand, or, at 

 least, to strain it. A great deal of 

 beef and pork is utterly unfit for ex- 

 portation by the use of unfiltered wa- 

 ter in making the brine. 



*' In packing provisions, the tier- 

 ces, barrels, &c., should be made 

 with great care and neatness. Clean, 

 handsome ash staves are preferred, 

 and of such other hard, close-grained 

 woods as will not stain the meat. 

 Tierces should have four iron hoops, 

 or three — one at each bilge and one 

 at each chime ; barrels^ with an iron 

 hoop at each chime. The fuller hoop- 

 ed the barrel or tierce is, the better." 



MECHANICAL POWERS. The 

 simple machines, the lever, pulley, 

 wheel and axle, rope machine, wedge, 

 and screw. 



MECHOACAX. Convolvulus pan- 

 duratus. Wild potato vine. A peren- 

 nial, herbaceous bindweed, with tu- 

 berous root, of a slightly cathartic 

 property. 



MECONIC ACID {(xom meconium, 

 opium). The acid with which mor- 

 phia is combined. It is tribasic, white, 

 crj'stalline, acid, and soluble in water 

 and alcohol : the solution turns red 

 when a per salt of iron is introduced 

 into it. Formula, 3 HO C14 HO,.-!- 

 G HO (Graham), with 6 atoms of wa- 

 ter of crystallization. Comenic and 

 pyro-meconic acids are derivatives. 



MECONIUM. Opium. The ex- 

 crement found in the intestines of 

 new-born animals. 



MEDIASTINUM. The portion of 



Tt 



the cavity of the chest made by the 

 folding of its membrane (pleura). 



MEDIC. The genus Medicago. 

 The principal species is the M. saliva, 

 lucern. They are mostly small an- 

 nuals, with minute leguminous flow- 

 ers, are all very nutritious and readily 

 propagated. M. lupulina, or black 

 medic, is indigenous, but small ; M. 

 falcata, yellow medic, has been recom- 

 mended tor cultivation, and is hardi- 

 er, although not so luxuriant or suc- 

 culent as lucern : it is perennial. 

 They all prefer a dry, calcareous, 01 

 marly soil. 



MEDICINES FOR CATTLE. See 

 Pharmacopceia. 



MEDIUM. In science, the sub- 

 stance in which any body is immer- 

 sed. It is called rare, dense, opaque, 

 or transparent, according to its na- 

 ture. It causes resistance to motion, 

 and, more especially, acts upon the 

 passage of light, bending (refracting) 

 it from its straight course. Astron- 

 omers are disposed to admit the ex- 

 istence of a very rare medium or 

 ether beyond the earth's atmosphere, 

 filling the space of our solar system. 



M E D L A R. Mcspilus Gcrmanica. 

 A European tree resembling the pear ; 

 the fruit is about two inches in di- 

 ameter, and flattened ; it is very hard 

 and austere until decayed, when it 

 becomes of a pleasant acid sweet- 

 ness. The Dutch and Nottingham 

 varieties are best ; but as the fruit 

 keeps only for a short time when 

 ripe, and is in no way handsome, it 

 is but little cultivated. The wood is 

 hard and tough, resembling that of 

 the apple and pear. It is propagated 

 in the same way as these trees. 



MEDULLA. Marrow, pith, the 

 pith of herbaceous plants. The me- 

 dulla oblongata is the uppermost por- 

 tion of the sj)inal marrow, which is 

 sometimes called the medulla, and its 

 membranous coverings the medulla- 

 rij sheath. The same term is used in 

 botany to designate the vessels sur- 

 rounding the pith of exogenous plants. 



MEDULLARY RAYS. The sil- 

 ver grain of wood, a prolongation of 

 the pith of trees f^rom the centre to 

 the bark, in exogens. 



493 



