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laid w=th fainfoin ; and the burnt ftraw was better in all 

 thofe crops than yard-duii'^. Burning gorfe in this manner 

 return! threat crops; but the expencc is too high. He is 

 clearly ot" opinion, that it is the warnnth from the fire that 

 lias the eTea, and not the aflies ; for the quantity is nothing, 

 and would blow away at one blaft. It is proper to obfr-rve, 

 fays he, that they do not value llraw ufed in feeding cattle 

 at mire than 4s. or j8. a ton. Mr. Mnllis of Lumber is of 

 the fam-- opinion, and thinks four tons are enough ; and never 

 kne«r that fill for turnips. Th s llraw burning hulbandry 

 the reporter found again at BcleHay. Mr. LloyJ, who, he 

 fhonid ohfervc, is an excellent fuMicr, thinks that it takes 

 fix tons per acre, which will lall longer in its effeft, and 

 be-.t the dung which that llraw would -nake, and in general 

 lall lor., 'er than common du-gi".g. Keeping much cattle, 

 he cannot pradife it, but highly approves it. In difcourfe 

 at Horn-calile ordinary on burning llraw, the practice, he 

 fays, was much reprobated ; yet an inllancc was produced 

 that fecm^d to make in favour of it. Mr. Elmhurll, of 

 Hazlcthorp, burnt twelve acres of cole-feed draw on eight 

 acres of the twelve, and the effed was very great, and feen 

 even for twenty years. He fowed wheat on it, four bufhels 

 an acre, and had five quarters : the four acres upon which 

 flothing was burnt, much llie better land, yet the crops on 

 the burnt part were by that mode equal to the reft. But in 

 another fimilar experiment for turnips, Mr. Rancliff ob- 

 lerved, the refult and the efFcft lafted only for_ one crop. 

 Mr. Kirkhara, who was in company, gave it as his opinion, 

 that, as cattle would not eat Hubble, it might be bcuclicial 

 to colled and ftack that, and, before turnip fowing, burn 

 it. The reverend Mr. Allington of Swinap has burnt on 

 the land for turnips, the long-ftraw dung from the furface 

 of the farm yard, and has had better turnips there than 

 where the dung was laid. This has been the cafe in two 

 experiments he has made." On llifFadhefive foils it is pro- 

 bable fomc advantage may be produced by the aftion of the 

 fire in this mode, but in other cafes it mull be a waftcfnl 

 practice. The nature of the land on which thefe trials were 

 made is not, however, mentioned. 



" About TathwcU," the reporter adds, " there is nO 

 burning llraw upon land ; Mr. Clough, Mr. Hyde, and Mr. 

 Pearfon, fcouted the idea of fuch a thing being common. 

 It has, however, been tried there, for Mr. Oldham of Elk- 

 ington did it, after ploughing for turnips, with long llraw 

 from the yard, and he fu^-cfeded well for the moft part." 



Burning of Land. See Paring and Burning. 



Burning of nuta's, ufth tnetalloruin, is either performed 

 by fire, or by corroGve falts ; which latter is alfo denominated 



C/EMFNTATION. 



The iirll preparation of moft ores is by uftion, or burning, 

 ■whereby to difpofe them for fufion. This is ufually per- 

 formed by txpofing them, without addition, to a naked fire; 

 fometimcs fixed alkalis and abforbents are added, to hinder 

 the avolation of the metalline particles. Some hold burning 

 in the Hone or glebe moft advantageous ; others burning in 

 the meal. Phil. Tranf. N^ 109. The bafer metals, tin 

 and lead, may be b'lrnt like plants to allies. For gold and 

 filver, the cafe is otherwife. 



Burning mountains. See Volcano, Earthc^uake, 

 Mountain, &c. See alfo ^Etna, Hecla, Vesuvius, 

 8cc. 



The ancients dcfcribe a meteor under the denomination of 

 turning buckler, clypeus aniens. Plin. H ft. Nat. lib. ii. 

 cap. 34. Mem. Acad. Infer, torn. vi. p. 95. 



Travellers into Italy defcribe a burning t'pot of ground at 

 Firenzuola, in the Apennines, out of which a crackling 

 £ame continually arifes, yet without any cleft for it to iffue 



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out at. MafFei fuppofes the fttams which the place yields, 

 to be a kind of native phofphorus aniens, which take fire on 

 their coming ir. contact with tlie a r. 



Burning, ammg Painters. — Seveml of the painters' co- 

 lours require burning, to fit them for ufe, as lamp-black, um- 

 ber, ivory, &c. 



The burning, or rather drying, of lamp-black, is perform- 

 ed by fettiiig a over the tire in an iron ladle, or crucible, till 

 110 fmoke arifes from it. To burn umber, they put it in 

 large lumps into a n.iked fire, where it is left till thoroughly 

 red-hot. Ivr.ry mull be burnt, to make a black, in two 

 crucibles, luted, covered with coals. 



Burning, in Enamel Pahillng. See Enamelling. 



Burning is alfo an operation in Pharmacy. Simples arc 

 frequently burnt in earthen-veflels, either to reduce them to 

 afties, as in the preparation of vegetable falts, or in order to 

 dry them, that they may be more commodioufly pulverized, 

 as is pratlifed in reijard of hartlhorn, &c. 



'Bv RS IS O p/.'ofpborus. See Phosphorus. 



BvKnisG plant. See Euphorbia. 



livfLSiKofpring, in Natural Hijlory. See Spring. 



Burning ■z.one, m Geography. See Torrid zone. 



BURNISHED gold oyjilver, denotes thofe m«tals laid 

 on any work or leaves, and afterwards pafTed over v/ith a 

 burnilher to heighten their luftre. 



BURNISHER. See Burnishing. 



BURNISHING, the operation of giving an uniform and 

 brilliant furface to a variety of fubftances by Iriclion, with a 

 polifhed hard inftrument ufually called a burnifher. 



The modes of pohture in ufe amongll artifans may, per- 

 haps, be all reduced to four: — the aiperities of a rough 

 furface may be removed by cutting off the protuberances, aa 

 \n planing; by abrading them, as \a filing and polijliing ; by 

 obtundinif them with the hammer, as in planifoing ; and by 

 accomplilbing the fame purpofe in the manner now under 

 our confi deration. 



It w ill be readily perceived, that the two latter operations 

 can only be performed on fuch fubftances as poflefs a certain 

 degree of malleability or duftility ; thofe whxh are brittle, 

 as glafs or hardened Heel, will neceftarily be incapable of be- 

 ing burnifhed. 



To fpeak of all the defcrlptions of artifans who ufe this 

 procefs would be to enumerate alinoft the whole of thofe 

 who work on metals. The inllruments with which it is per- 

 formed are alfo as various as the furfaces to be fubjefted to 

 their action : we fliall therefore only fpeak of fuch as are 

 ufed for plane furfaces. The burnilher in this cafe is gene- 

 rally a piece of very hard fteel three or four inches long, and 

 about one eighth of an inch thick, with a fomewhat convex 

 edge, not much unhke that of the fteel which is commonly 

 ufed for ftrikiiig fire, all the angles of it being fmoothly 

 rounded off, fo that the longitudinal feClion of the part to 

 be applied to the fubjeft is a femi-elhpfe of great eccentricity, 

 the edge of which is nearly femi-cylindrical. It is applied 

 in different ways according to the nature and extent of its 

 ufe in the workftiop. The manufafturers of ornaments for 

 ftoves, who ufe a great number of burnifhed plates of foft 

 fteel, frequently infert it into the lower extremity of a 

 wooden pole, which is fufpended over the work-bench, from 

 one end of a ftrong wooden Ipring fixed horizontallj' in a 

 frame attached to the ceiling, and prcfling downwards ; fo 

 that the workman has only to pafs it backwards and for- 

 wards horizontally at right angles to its own plane, over the 

 furface of the plate, its preffure being produced, or, at leaft, 

 affifted by the adlion of the fpring. Some workers in metal 

 apply the burniftier by attaching it to the underfide of a 

 lever, which has a handle at one end, and is hooked at the 



other 



