Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/622

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DRESSING of ores; the preparing them as they come rough from the mine, for the working by fire. This is done feveral wa\s in different countries and in refpe£t to the different ores of the metals ; in Devonfhire we have a very eafy method, which is fo expeditious, and fo good for all the purpofcs, that it is worthy copying in other places. After the ore is dug, it is tolled up by hand from il nimble tu fhamble by the fhovel- men in the mine, and drawn up in buckets by a wynch at the top of the fliaft. As loon as the whole quantity for one drefhng is brought up, the large ftones are broken, and the whole is then carried to the mills, where one horfe turns a wheel that moves the machines for poudering a great quantity or it ; thefe are called the ftamping or knocking mills. The ore is un- loaded at the head of the pafs or entrance intothele mills ; this pafs is made of two or three bottom boards and two fide boards, in form of a hollow trough, and ftands in a flaming direction. The ore by its own weight is carried down this trough, and lodges itfelf in the coffer. The coffer is a long fquare box made of the firmeft timber, and of three feet long, and a foot and half broad ; the ore is not fuffered to fall into this all at once, but is flopped ovar the mouth of the trough by a crois board, where a cock turns in a quantity of water at the fame time, which wafhes down juft as much of the ore with it in- to the trough, as there ought to be. In this coffer there are three lifters placed between two ftrong board leaves, having two braces or thwart pieces on each fide to keep them fteady, as a frame with {lamp heads. Thefe heads are of iron, and weigh about thirty or forty pounds, a-piece, and ferve to the breaking the lumps of ore in the coffer. The lifters are about eight foot long, and half a foot fquare. They are always made of heart of oak, and have as many in- timbers or guiders between them ; they are lifted up in order, by a double number of toppits, which are fattened to as many arms paffing diametrically thro' the great beam, which is ei- ther turned by the wheel and horfe, or where there is con- veniency of water, by an overfhot water-wheel on two boul- ftcrs. The tappets exactly but eafily meet with the tongues, which are fo placed in the lifters, as that they eafily Hide from each other, and fuffer the lifters to fall with great force on the ore in the trough. The frequent pounding of thefe foon reduces the large maffes into a fort of fand, which is warned out of the trough by the continual current of the water from the cock thro' a brafs grate, which is placed at one end of the coffer between two iron bars.

The powdered ore is conveyed out of the trough into the launder, which is a trench cut in the floor of eight foot long, ' and ten foot over, this is flopped at the lower end with turf, fo that the water is all fuffered to pafs away, and the powder of the ore is flopped. Thus the launder by degrees fills up with the drcfled ore, and this is removed out with {hovels as occafion requires. The launder is divided into three parts, the forehead, the middle, and the tail ; that ore which lies in the forehead, that is, within a foot and half of the grate, is al- ways the richeft and beft, and is laid up in a heap by itfelf; the middle and tail afford a poorer ore, and thefe are fomc- times laid up in feparate heaps ; fometimes thrown into one heap together.

DRIFT [Cycl.) — Drift, in mining, a pafTage cut out under the earth betwixt fhaft and {haft, or turn and turn, orapaflage or way wrought under the earth to the end of a meer of ground, or part of a meer. See Houghton's Compl. Miner. in the Explan. of the Terms.

DRILL, or DiULL-i?ov,a name given to an inflrument ufed in the new method of horfehoing husbandry for fowing the land. The Drill is the engine that plants the corn and other feeds in rows ; it makes the channels and fows the feeds in them, and covers them with earth when fown, and all this at the fame time, and with great expedition. The principal Parts of the Drill are the feed-box, the hopper, the plow and its harrow. The feed-box is the chief of thefe, it meafures or rather numbers out the the feeds which it receives from the hopper, and is for this purpofe as an artificial hand, but it de- livers out the feed much more equally, than that can be done by a natural hand. The plow and hopper are drawn by a horfe, and by thefe the ground is opened, and the feed is de- pofited in it; the harrow follows, and lightly rakes in the earth over them. When the ground is fine, and the feeds fmall, a hurdle with fome prickly bufhes fattened to its under part, will feive better than the harrow. The whole apparatus for this method of fowing, is finely defcribed and illuftrated with figures by Tull in his Horfehoing Husbandry, to which we refer.

Drill, in mechanics, a fmall inflrument for making fuch holes as punches will not conveniently ferve for. Drills are of va- rious fizes, and are chiefly ufed by fmiths and turners. Vid. Moxon. Mech. Exerc. p. 6. 234.

It is a very well known fa£t, that a Drill made of iron, has frequently not only a polarity, but fo ftrong an attractive vir- tue of the magnetick kind, that it will fufpend a common needle from its point, ft is ufually fuppofed that a Drill ac- quires this polarity by boring iron. But it is not only by bo-

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ring of iron, that this power is obtained, but in the very mak- ing. As foon as one of them -is finifhed and hardened if point becomes a north pole before it has ever been worked either in iron or any other materials, fo that of the great num bers of thefe inftruments found in a fhop, endued with this power, it is to be fuppofed that more of them owe it to their original make, than to any after ufe. All pieces of wrought iron which in fhape refemble Drills, that is, which are of a long and {lender form, will not only have this polarity but they will change it on being placed for fome time in an in- verted poflure, and that which was the oppofite to the north pole, by Handing downwards will be the north pole. This has been an old obfervation, but on a fair experiment, it does not prove to be true in all things without exception, tho' it be fo in moft particulars. The larger pieces of iron feem to be moft eafily influenced in their polarity, by changing their po- fition, but the fmall ones will fometimes be found to have fixed poles, which no change of poflure will alter. Philof. Tranf. N°. 246. See Magnet,

DRILLING, is popularly ufed for exercifing of foldiers.

The word is derived from the French Drille, which fignifies a rawfoldier: Calo, miles exigui pretii, fays Le Clerc a, who derives Drille from the Hebrew chel, fignifj ing all, or a whole. As this derivation fecms no fmall paradox, we fhall here in- fert this learned Author's deduction. i°. From chol is formed the Greek oa© totus. 2°. From l\Qr is formed the Latin Joins. 3 . From folits, comes folidus. 4 , From folidus is derived Jblidum, a piece of money. 5 . Yiomfolidum comes jblidarius, or a loldier receiving a folidttm. 6°. From folidarius, foldarius is eafily derived, and hence the French foudar. 7°. From foudar comes the diminutiveyiWnV/f. 8°. F rom foudrille, the tranfition per aphezreftn to Drille is eafy. This etymology is applauded by Menage; but he, as Le Clerc b obferves, does not afcend to the Hebrew fpring ; in which the reader may perhaps think him judicious. [ 3 Le Clerc, Differt. Etymol. ad Math. Martinii Lexicon. Philolog. •> Id. ibid.]

DRINK (Cycl.) — The firft Drinks of mankind were certainly water and milk; but the love of luxury and debauchery foon introduced the art of preparing intoxicating and inebriating Drinks out of vegetables. The vine gave the firft of thefe liquors; after this, wheat, barley, millet, oats, rice, apples, pears, and pomegranates; and after thefe the juices drained from the pine, fycamore and maple were brought to this ufe; in latter times, roots, berries, and the pith of the fu gar cane, have been employed for the fame purpofes : honey alfo is at prefent in fome repute, but before the ufe of the other things here mentioned, the vinous liquor made of honey and water was in the very higheft eftimatiun. The bees were natural purveyors, and their ftores were one of the firft delicacies probably of the human race. It was very mtural to attempt the meliorating fo raw a drink as water, by an addi- tion of this fweet fubftance ; and fuch a mixture needing on- ly time for fermentation to become vinous, accident might foon lead to this difcovery. Mead therefore may naturally be fuppofed to have been one of the fiift ftrong liquors in ufe in the world, and among the very oldeft writers among the Greeks we find it named as a thing well known. Homer, Hefiod and Ariftophanes all give plain proofs of their having been acquainted with it ; and Orpheus reprefents night coun- felling Jupiter to make Saturn drunk with mead, and then to dethrone and caftrate him. The people who have ftudied the human frame to moft purpofe, all agree, that amongft the ftrong Drinks, wine is the moft pernicious ; and that good water, milk, beer and cyder are greatly preferable to it, none of them bringing on the variety of diforders, to which immo- derate wine drinkers are fubjecf, fuch as decay of fight, trem- bling of the limbs, &c.

Mr. Boyle mentions an acquaintance of his who ufed to drink but once in feveral days, and that in no great quantity, yet fweat freely, and had his urine in juft quantity. See Works Abr. Vol. i. p. 306.

DRINKLEAN, in our old writers, a fcot-ale or contribution of the tenants towards a potation, i. e. ate provided to entertain the lord or his fteward. In fome records it is written, Po- tura Drinklean.

DKIVE-Bolts, in {hip building. See Bolts, Cycl.

DRIVER, the name given by our fportfmen to an inrtrument ufed in the taking pheafanc powts, in the method called driv- ing. This inflrument confifts only of a parcel of ozier wands fuch as are ufed by the basket- makers, which are made up into a bundle, or fort of great whisk, and fattened in a handle ; and to prevent their fpreading too much at the points are tied round in one or two places in the length ; with this inflrument the fportfman having fixed his nets, drives the young birds in- to them. See Driving.

DRIVING, amongft fportfmen, a term applied to the taking of young pheafants, and fome other birds in nets of an open ftructure. The method of doing this, is, when an eye of pheafants are found, the ground all about is to be fearched, for the finding of their principal haunts. The induftrious fearch-