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Bread. The Forms of Baking are various, but may be reduced to two; the one for unleavened, the other for leavened Bread : for the firft the chief is Mancbet-Bakmg, the Procefs whereof is as follows. The Meal ground and bolted is put into a Trough, and being opened "in the Mid- dle, to aBuihel is poured in about three Ruts of warm Ale, with Barm and Salt to feafon it. This is kneaded together with the Hands thro the Brake; or for want thereof with the Feet thro a Cloth : after having lain an Hour to fwell, 'tis molded into Manchets; which, fcotch'd in the Middle,' and prick'd a-Top to give room to rife, are baked in the Oven by a gentle Fire. For the fecond, call'd Cheat-Bread-Ba- king, 'tis thus : The Meal being in the Trough, fome Lea- ven (faved from a former Batch fill'd with Salt laid up to four, and at length diflblvcd in warm Water) is ftrain'd thro a Cloth into a Hole made in the Middle of the Heap, and work'd with fome of the Flower to a moderate Confluence; this is covered up with Meal, where it lies all Night, and in the Morning the whole Heap is ftirr'd up and mixt to- gether with a little warm Water, Barm and Salt, by which it is feafon'd, ftiffen'd, and brought to an even Leaven : 'tis then kneaded or trodden, molded and baked as before.
The Learned are in great doubt about the Time when Baking firft became a particular Profeflion, and Bakers were introduced. 'Tis generally agreed they had their Rife in the Eaft, and pafs'd from Greece to Italy after the War with Pyrrhus, about the Year of Rome 583. Till -which time every Houfewife was her own Baker : For the Word Piftor, which we find in the Roman Authors, be- fore that time fignified a Perfon who ground or pounded the Grain in a Mill or Mortar to prepare it for Baking, as Varro obferves. According xaAthenms, the Cappadocians were the mod applauded Bakers, after them the Lydians, then the Phxnicians. To the foreign Bakers brought in- to Rome, were added a Number of Freed-Mcn, who were incorporated into a Body, or, as they call it, a College; from which neither they nor their Children were allowed to retire. They held their Eftefls in common, and could not difpofe of any Part of 'em. Each Bake-boufc had a 'patronus, who had the Supcrintendency thereof; and thefe 'Patroni elected one out of their Number each Year, who had the Intendence over all the reft, and the Care of the College. Out of the Body of the Bakers were every now and then one admitted among the Senators. To preferve Honour and Honefty in the College of Bakers, they were exprefly prohibited all Alliance with Comedians and Gla- diators; each had his Shop or Bake-houfe, and they were diftributed into 14. Regions of the City. They were ex- cufed from Guardianfhips and other Offices, which might divert 'em from their Employment. See College.
BALANCE, Libra, or the Scales, one of the fix fim- ple Powers in Mechanicks, ufed principally for determining the Equality, or Difference of Weights in heavy Bodies, and confequently their Mafles or Quantities of Matter. The Balance is of two Kinds, viz. the Antient and Modern. TheAntient otRoman, call'd the Statera Romana, or Steel- yard, confifts of a Lever or Beam, moveable on a Centre, and fufpended near one of its Extremes : On one fide the Centre are applied the Bodies to be weigh 'd, and their Weight; meafured by the Divifions mark'd on the Beam, in the Place where a Weight moveable along the Beam being fix'd, keeps the Balance in JEquilibrio. This is {HU in Ufe in Markets, t$c. where large Bodies are to be weigh'd. See Statera.
The Modern Balance, now ordinarily in ttfe, confifts of a Lever or Beam fufpended, exactly by the Middle; to the Extremes whereof are hung Scales. In each Cafe the Beam is call'd. the Brachia; the Line on which the Beam turns; or which divides its Brachia, is call'd the Axis, and when confider'd with regard to the Length of the Brachia, is but efteem'd a Point, and call'd the Centre of the Balance; and the Places where the Weights are applied, the Points of Sufpenfion or Application. In the Roman Balance therefore, the Weight ufed for a Countetbalance is the fame, but the Points of Application various; in the Common Balance, the Counterpoife is va- rious, and the Points of Application the fame. The Prin- ciple on which each is founded is the fame, and may be conceiv'd from what follows.
^Doctrine of the Balance.
The Beam AB {'Plate of Mechanicks, Fig. 9.) the prin- cipal Part of the Balance, is a Lever of the firft kind, which (inftead of refting on a Fulcrum at C, the Centre of its Motion) is fufpended by fomewhat faftened to C, its Centre of Motion. Hence the Mechanifm of the Balance depends on the fame Theorem as that of the Lever, (See Lever). Wherefore, as the known Weight is to the un- known, fo is the Diftance of the unknown Weight from the Centre of Motion to the Diftance of that of the known Weight, where the two Weights will counterpoife each other; confequcntly the known Weight lhews the Quan- tity of the unknown Weight. Or thus, the Action of a
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Weight to move a Balance is by fo much greater, as the Point preffed by the Weight is more diftWnt from the Centre of the Balance, and that Action follows the Proportion of the Diftance of the faid Point from that Centre. When the Balance moves about its Centre, the Point B defcribes the Arch B b ( Fig. 10. ) whilft the Point A defcribes the Arch A a, which is the big- geft of the two; therefore in that Motion of the Ba- lance, the Action of the fame Weight is different, accor- ding to the Point to which it is applied : Hence it follows, that the Proportion of the Space gone thro by that Point at A is as A a, and at B as B b; but thofe Arches are ro one another as CB, CA.
Varieties in the Application of the Balance.
If the Brachia of a Balance be divided into equal Parts, one Ounce applied to the ninth Divifion from the Centre, will equiponderate with three Ounces at the third; and two Ounces at the fixth Divifion aft as ftrongly as three at the fourth, fife. Hence it follows, that the Action of a Power to move a Balance, is in a Ratio compounded of the Power itfelf, and its Diftance from the Centre; for that Diftance is as the Space gone thro in the Motion of the Balance. It may. be here obferv'd, rhat the Weight equally preffes the Point of Sufpenfion at whatever Heighr it hangs from it, and in the fame manner as. if it was fixed at that very Point; for the Weight at all Heights equally ftretches the Cord by which it hangs.
A Balance is faid mbtinMqailiirio, when the Actions of the Weights upon each Bracbium to move the Balance, are , equal, fo as mutually to deftroy each other. When a Ba- lance is in JEquilibrio, the Weights on each Side are faid to equiponderate: unequal Weights may alfo equiponde- rate; but then the Diftances from the Centre muft be re- ciprocally as the Weights. In which cafe, if each Weight be multiplied by its Diftance, the Products will be equal; which is the Foundation of the Steelyard. Thus in a Ba- lance whofe Brachia are very unequal; a Scale hanging at the Jhorteft, and the longcft divided into equal Parts : It fuch a Weight be apply'd' to it, as at the firft Divifion lhall equiponderate with one Ounce in the Scale; and the Body to be weigh'd be put into the Scale, and the above- mentioned Weight be moved along the longeft Bracbium, till the JEqailibritim be found; the Number of Divifions between the Body and the Centre ft-iews the Number of Ounces that the Body weighs, and the Sub-Divifions the Parts of an Ounce.
On the fame Principle alfo is founded the deceitful Ba- lance, which chea'ts by the Inequality of the Brachia; for Inftance : Take two Scales ot unequal Weights, in the Pro- portion of 9 to iOj and hang one of them at the tenth Divi- fion ot the Balance above-defcribed, and the other at the ninth Divifion, fo that there may be an JEquilibrimn; if then you take any Weights, which are to one another as 9 to 10, and put the firft in the firft Scale, and the fecond in the other Scale, they will equiponderate. Several Weights hanging at feveral 'Difiances on one Side, may eqmponde^ rate with a finglc V/eigbt on the other Side: To do this it is required, that the Product of that Weight, by its Dif- tance from the Centre, be equal to the Sum of the Pro- ducts of all the other Weights, eaeh being multiplied by its Diftance from the Centre : To demonftrate which, Hang three Weights, of an Ounce each, at the fecond, third, and fifth Divifions from the Centre, and they will equipon- derate with the Weight of one fingle Ounce applied at the tenth Divifion of the other Bracbium; and the Weight of one Ounce at the fixth Divifion, and another of three Ounces at the fourth Divifion, will equiponderate with a Weight of two Ounces on the other Side at the ninth Divifion. Several Heights unequal in Number on either Side, may equiponderate : In this cafe, if each of them be multiplied by its Diftance from the Centre, the Sums of the Product on either Side will be equal; and if thofe Sums are equal, there will be an JEquilibrhm: To prove which, hang on a Weight of two Ounces at the fifth Divifion, and two others; each of one Ounce, at the fecond and feventh, and on the other Side hang two Weights, each alfo of one Ounce, at the ninth and tenth Divifions, and thefe two will equiponderate with thofe three.
To the Perfection of a Balance 'tis required, that the Points of Sufpenfion be exactly in the fame Line as the Centre of the Balance; that they be precifely cqui-diftant from that Point on either Side; that the Bracbia be as long as conveniently they may; that there be as little Friction as poffiblc in the Motion of the Beam and Scales; and laftly, that the Centre of Gravity of the Beam, be placed a little below the Centre of Motion, See Motion, Mechanicks, &c.
Balance of the Air, is ufed for the Weight of that Fluid, whereby, according, to its known Property,' it preffeth where 'tis leaft refilled, till it is equally adjufted in all Parts. See Air. See alfo Gravity, and Barometer:
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