CHARD. 



CHEESE. 



to the secretions from the roots of the plants 

 which grew in it. 



" A plant placed in a closed vessel in which 

 the air, and therefore the carbonic acid, cannot 

 be renewed, dies exactly as it would do in the 

 vacuum of an air-pump, or in an atmosphere 

 of nitrogen or carbonic acid, even though its 

 roots be fixed in the richest mould. 



"Plants do not, however, attain maturity, 

 under ordinary circumstances, in charcoal 

 powder, when they are moistened with pure 

 distilled water instead of rain or river water. 

 Rain water must, therefore, contain within it 

 one of the essentials of vegetable life ; and it 

 will be shown, that this is the presence of a 

 compound containing nitrogen, the exclusion 

 of which entirely deprives humus and char- 

 coal of their influence upon vegetation." (Lie- 

 big's Or<inic Chemistry.) 



" Dr. Webster, editor of the American edi- 

 tion of Liebig's Organic Chemistry, observes : 

 'A few years since, I had an opportunity of ob- 

 serving a striking instance of the effect of car- 

 bonic acid- upon vegetation in the volcanic 

 island of St. Michael (Azores). The gas is- 

 sued from a fissure in the base of a hill of tra- 

 chyte and tuffa from which a level field of 

 some acres extended. This field, at the time 

 of my visit, was in part covered with Indian 

 corn. The corn at the distance of ten or fif- 

 teen yards from the fissure, was nearly full 

 grown, and of the usual height, but the height 

 regularly diminished until within five or six 

 feet of the hill, where it attained but a few 

 inches. This effect was owing to the great 

 specific gravity of the carbonic acid, and its 

 spreading upon the ground, but as the distance 

 increased, and it became more and more min- 

 gled with atmospheric air, it had produced less 

 and less effect." 



CHARD. See BEET. 



CHARLOCK (Sax. cepiice ). PI. 10 g. A 

 troublesome weed, which abounds in most ara- 

 ble soils, and is very difficult to expel. In Eng- 

 land it is frequently called chadlock, catlork, mr- 

 lock, corn-kale, and white-rape. There are four dif- 

 erent species of plants,says Sinclair, confounded 

 under the name of charlock, viz. Sinapis ctrven- 

 sis, or common wild mustard ; yellow b 1 

 in May; annual. S.'nigra, black, or Durham 

 mustard ; blossom, pale yellow, in June ; an- 

 nual. Raphanus raphanistnirn, wild radish ; 

 straw-yellow blossom, in June and July ; an- 

 nual. Brassica napus, wild navew (this last is 

 the least common) ; yellow blossom, in May ; 

 biennial. 



The seeds derived from the hard pods of 

 the variety of the yellow-flowered charlock, 

 called wild mustard, are collected in England 

 and sold under the name of Durham Mustard. 

 They furnish by expression an excellent oil, 

 which it has been thought might be rendered 

 profitable. In Germany 30 Ibs. of pure lamp- 

 oil has been obtained from 100 Ibs. of seed. 



Charlock has been introduced from Europe, 

 and has become quite extensively naturalized in 

 several parts of the United States. Being an 

 annual plant it is very difficult to get rid of, 

 and when once in possession of a spot will 

 long bid defiance to all attempts made for its 

 total extirpation. It infests clayey grounds, 

 40 



such as are particularly well adapted to the 

 culture of wheat and other most valuable 

 grains. Its seeds contain a preservative oil, 

 which, with their great firmness enables them 

 to remain sound under ground for an almost 

 unlimited period. Those only Avhich are 

 brought by tillage within a certain distance of 

 the surface, sprout and grow, whilst the deeper 

 covered remain for the production of another 

 crop when brought up by the plough suffi- 

 ciently near the surface. The only practicable 

 mode of eradicating this and other pests of an- 

 nual growth, is to prevent the plants from coming 

 to seed, by cutting down when in blossom. The 

 greatest care should be taken to inspect seed- 

 grain before sowing, and see that no seeds of 

 charlock or other troublesome weeds are in 

 the samples. The leaves, flowers, long, round 

 and irregular seed-pods and odour of the root 

 are very similar to those of the common 

 radish. Farm stock generally are fond of the 

 plant, and especially sheep, which, when it is 

 possible to turn upim the field sufficiently 

 early, will keep it from growing up to seed. 



In Ireland and the northern parts of Europe, 

 as well as in some parts of America, young 

 charlock is boiled for greens in the same man- 

 ner as cabbage-sprouts, &c. The flowers are 

 much frequented by bees. (Weeds of jQgricul- 

 twe, p. 45 ; Smith's Flow, vol. iii. p. 321-1!.) 



CHARRING OF POSTS. The reducing 

 that part of the surface of posts which is to be 

 put into the ground to the state of charcoal. 

 This method is highly useful where the parts 

 are to be placed in wet situations, or to stand 

 between wet and dry. This was a practice 

 common to the ancients. 



CHEAT AND CHESS. See DARNEL. 



CHEDDER CHEESE. A kind of cheese so 

 named from its being made at Chedder, a vil- 

 lage near the Mendip-hills in Somersetshire, 

 famous for its pastures. The richness and 

 fine flavour of Chedder cheese is supposed to 

 be derived chiefly from a species of Agrostis 

 upon which the cows feed. 



CHEESE (Lat. caseus; Sax. cere). A well- 

 known kind of food, prepared from milk by 

 coagulation, and separated from the serum or 

 whey, by means of pressure, after which it is 

 dried for use. See BUTTER. Cheese has been 

 made from a very ancient period ; it is men- 

 tioned by Job, and also by Homer. According 

 to Strabo, our British ancestors did not under- 

 stand how to make cheese, a deficiency with 

 which their descendants cannot now well be 

 charged. 



Good cheese, says Dr. Thomson, melts at a 

 moderate heat ; but bad cheese, when heated, 

 dries, curls, and exhibits all the phenomena of 

 burning horn. From this it is evident that 

 good cheese contains a quantity of the peculiar 

 oil of cream ; hence its flavour and smell. 

 Proust found in cheese a peculiar acid, which 

 he called the caseic. (System of Chem. vol. iv. p. 

 499.) 



The best season for making cheese is during 

 those months when the cows can be fed on the 

 pastures ; that is, from the beginning of May 

 till towards the end of September, or, in favour- 

 able seasons, the middle of October. In Eng- 

 , land, on many of the large dairy farms, in se- 

 2D 313 



