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. lo, to make him carry or draw up bill: for if the the centre of the gravitating force), or be some hill be steep, three men will do more than a horse, other thing which does not appear. each man climbing up faster with a burden of Again, forces are either constaut or variable. 100lb, weight, thau a horse that is loaded with Constant forces are such as remain and act con3001b.: a difference which is owing to the position tinually the same for some determinate time. of the parts of the human body being better Such, for example, is the force of gravity, which adapted to climb, than those of a horse.

acts constantly the same upon a body while it On the other hand, the best way of applying the continues at the same distance from the centre of force of a horse, is the horizontal direction, in the earth, or from the centre of force, wherever which a man can exert the least force: thus, a that may be. man that weighs 140lb. when drawing a boat along Here the following nine propositions will often by means of a rope coming over his shoulders, be of utility : cannot draw above 27/b., or exert above sth part of 1. If different forces are successively applied to the force of a borse employed to the same pure accelerate equal quantities of matter from quiespose; so that, in this way, the force of a horse is cence, the spaces described in any given time will equal to that of seven men,

be in the same proportion with the forces. The best and most effectual postare in a man, 2. If the same force impels different quantities is that of rowing ; when he not only acts with of matter, for any given time, the spaces described more muscles at once, for overcoming the resistfrom quiescence will be inversely as the quanti. ance, than in any other position, but also as he ties of matter moved. pulls backwards, the weight of his body assists by 3. If the force be increased or diminished, in the way of lever. See Desaguliers's Exp. Philos. v. 1. p. same proportion with the mass moved, the spaces 241, where several other observations are made re- described from rest, in the same time, will be lative to force acquired by certain positions of the equal. body; from which, that author accounts for most 4. If a body is moved from quiescence, during feats of strength and activity. See also a Memoir any given tinie, it will, at the end of that time, on this subject by M. De la Hire, in the Mem. have acquired such a velocity as will, if continued Roy. Acad. 1729; or in Desaguliers's Exp. &c. uniform,carry it, in the same time, through double p. 267, &c. who has published a translation of the space which the body has already described to part of it with remarks.

acquire that velocity. Force is distinguished into motive and accelera- 5. If the same force acts on the same mass, for tive or retardive.

different times, the velocities generated will be reMotive force, otherwise called momentum, or spectively in the same proportion with the times force of percussion, is the absolute force of a body in which the given force acts. in motion, &c.; and is expressed by the product 6. If any given quantity of matter is moved from of the weight or mass of matter in the body mula quiescence by different forces, during a given time, tiplied by the velocity with which it moves. But, the velocities acquired will be in the same pro

Accelerative force, or retardive force, is that portion with the forces. which respects the velocity of the motion only, 7. If a given force impels different quantities of accelerating or retarding it; and it is denoted by matter for the same time, the velocities generated the quotient of the motive force, divided by the will be inversely as the quantities of matter. mass or weight of the body. So,

8. If a body be moved from quiescence, through if m denote the motive force,

the same space by different forces, the velocities and b the body, or its weight,

generated will be in a subduplicate ratio of the and f the accelerating or retarding force,

forces.

9. If a given quantity of matter is impelled from then is fast

quiescence, through different spaces, by the action of the same force, the velocities generated will be

in a subduplicate ratio of the spaces described. In centripetal forces, the absolute quantity is

In the case of a constant force F, acting upon a defined from the magnitude, or at least from the body b, for any time t, we have these following strength and efficacy of the central body. The

theorems; putting accelerating is that force as perpetually decreasing

f=the constant accelerating force=F<b, in the increase of the distance, et contra. The

1:=the velocity at the end of the time t, moving force is the weight itself, which arises from

s=the space passed urer in that time, by the the body or mass drawn into the accelerating

constant action of that force on the body: force. From whence, the absolute force, being and fg=1614 feet, the space generated by gravity given, the moving force in a given body will be as in 1 second, and calling the accelerating force of the accelerating; and, the accelerating being given, it will be as the body. These three forces, there gravity l; then is fore, are referred to three things, to bodies, to the

s={lv=igst places of bodies, and to the centre of force. The

2gf motive force respects the body, and the endeavour

2$ and propension thereof to the centre, as com

v=gft= 72gfs; pounded of the endeavours and propensions of all

2s the parts. The accelerating refers to the place of the body in the medium, as the efficacy of the same absolute force, according to divers distances

2s from the centre: and, the absolute force respects

fem the centre or central body itself, as endowed with

gt gla 2gs some power, without which the moving forces are Variable forces are such as are continually not propagated round about; whether that power changing in their effect and intensity; such as the or cause be the central body (as the magnet in force of gravity at different distances from the the centre of the magnetic force, or the earth in centre of the earth, which decreases in proportion

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as the square of the distance increases. In va. pio, to take.) A surgical instrument with which riable forces, theorems, similar to those above, may extraneous bodies or other substances are exbe exbibited by using the fluxions of quantities, tracted: also an instrument used occasionally and afterwards taking the fluents of the given by men midwives to bring the head of the fetluxional equations. And hereia consists one of tús through the pelvis. the great excellencies of the Newtonian or modem analysis, by which we are enabled to manage, and forces, drives, or constrains. 2. The embolus

FOʻRCER. s. (from force.) 1. That which compate the effects of all kinds of variable forces, whether accelerating or retarding. Thus, using

of a

pump working by pulsion (Wilkins). the same notation as above, for constant forces,

For an account of Trevithick's temporary viz. f the accelerating force at any instant, & the forcer to produce a constant stream, consult time a body has been in motion by the action of Nicholson's Journal, No. 9. N. S., or Gregothe variable force, o the velocity generated in that ry's Mechanics, vol. ii. p. 197. time, s the space run over in that time, and g=324 FORCHEIM, a strong town of Franconia, fact; tben is

in the bishopric of Bamberg. It is seated at

the confluence of the Wisent and Reduiz. di;

Lat. 49. 44 N. Long. 11. 2 E.

FOʻRCIBLE. a. (from force.) 1. Strong; -=gft; ;

mighty (Milton).

2. Violent; impetuous (Prior). 3. Efficacious : active; powerful (Bacon). 4. Prevalent; of great influence (Raleigh). 5. Done by force; suffered by force (Swift). 6. Valid; binding; obligatory.

FORCIBLE ENTRY AND DETAINER. ForIn these four theorems, the force f, though va

cible entry, is a violent actual entry into a riable, is supposed to be constant for the indefi. house or land, &c. or taking a distress of any nitely small time i ; and they are to be used in all person, armed, whether he offer violence or cases of variable forces, as the former ones in con- fear of hurt to any there, or furiously drive any stant forces; viz. from the circumstances of the out of the possession; if one enter another's problem under consideration, deduce a general ex- house, without his consent, although the doors pression for the value of the force S, at any inde. be open, this is a forcible' entry punishable by finite timet; then substitute it in one of these the law. theorems, which shall be proper to the case in And an indiciment will lie at common law hand; and the equation, thence resulting, will de- for a forcible entry, though generally brought trmine the corresponding values of the other on the several statutes against forcibly entry, quantities in the problem. le is also to be observed, that the foregoing imprisonment.

The punishment for this offence is by fine and theorems equally hold good for the destruction of FORCIBLE MARRIAGE. If any person shall inotion and relocity, by ineans of retarding or re- take away any woman having lands or goods, sisting forces, as for the generation of the same by

or that is heir apparent to her ancestors, by means of accelerating forces.

FORCES, CENTRAL, CENTRIFUGAL, &c. See the force and against her will, and afterwards she respective words.

be married to him, or to another by his proFORCE COERCITIVE, the name given by Cou- curement; or defiled; he, and also the

prolotub to the resistance opposed by the moleculæ of curers, and receivers of such a woman, shall çertain bodies to the motion of the electric fluid, be adjudged principal felons. And by 39 Eliz. when it endeavours to escape from them. This c. 9, the benefit of clergy is taken away from force augments with the defect of the conducting the principals, procurers, and accessaries bepower.

fore. And by 4 and 5 Phil. and Mary, c. 8, FORCE OF COMBINATION, is that in virtue of if any person shall take or convey away any una which the particles of two or more heterogeneous inarried woman, under the age of sixteen budies become so intimately united, that the resalt of their union is a body which has none of the (though not attended with force), he shall be properties of the constituents.

inprisoned two years, or fined, at the discreFORCE EXPANSIVE, See ExPANSION.

tion of the court; and if he deflower her, or FORCE OF TORSION, the effort made by a thread contract matrimony with her without the con, or wire, which has been twisted, to return to its sent of her parent or guardian, he shall be imformer state.

prisoned five years, or fined in like manner. FORCE PROJECTILE. See PROJECTILES. And the marriage of any person under the age

FORCEDLY. ad. (from furce.) Violently; of twenty-one, by licence, without such conconstrainedly; unnaturally (Burnet).

sent, is void. FOʻRCEFUL. a. (force and full.) Violent; FORCIBLENESS. s. Force; violence. strong; impetuous (Pope).

FOʻRCIBLY. ad. (from forcible.) 1. FORCEFULLY. ad. (from forceful.) Vio- Strongly; powerfully (Tillotson). 2. Impelently; impetuously.

tuously; with great strength. 3. By violence; FOʻRCELESS. a. (from force.) Having by force (Hammond). little force; weak; feeble; impotent.

FORCING, in garrlening, the art of raising FORCEPS. (forceps, -cipis, quasi ferri- and producing plants

, flowers, and fruits, by ceps, as being the iron with which we seize means of artificial heat. It is accomplished, any thing hot, from ferrum, iron, and can either by the gentle moist heat that is 'evolved

during the fermentation and decomposition of the dung may penetrate into the frame ; raised stable dung, tanner's bark, and other similar five, six, or seven feet high behind, and only materials, or by the use of actual fire in stores, ten or twelve inches high in front, raising both fues, and other contrivances for the purpose. ends answerable to the front and back; the

The forner of these methods is principally glass work to range, from the upright in front, employed in raising cucumbers, melons, and sloping upward towards the back wall, to about some other fruits, and the latter in producing a foot width at top, there resting the ends upon pine apples, various kinds of wall fruits, and proper frame work of wood; and bars or bearseveral other sorts of vegetable productions. ers, three inches in width, ranged sloping The great difficulty in the management of this from the back to front, for the support of the process, is that of adapting and regulating the lights, as in common hot-bed frames, and the heat, of whatever sort it may be, in such a top of all boarded wind and water tight; havnianner as to promote and bring forward the ing sometimes withinside two or three ranges plants in the most perfect and healthy growth, of narrow shelves, along the back and ends, without their sustaining injury either by a de- for pots of small plants, and the bottom levelficiency or excess. The various methods of led, on which to place pots of larger kinds; effecting this in the most perfect manner are or shelves may be made, rising one above anfully described under the culture of the differ- other, quite from the front, half way up the ent trees, plants, and vegetables that require back wail, in order to place the lowest plants such treaiment in their cultivation. It is by in front, the others in order behind ihem, this process that different sorts of vegetable pro- rising gradually to the tallest in the back ductions, fruits, and flowers are afforded at rows. much earlier periods than could otherwise be In working these frames, after having placed the case, and it of course constitutes an import- the pots of plants in regular order, the lights ant branch of practical gardening.

are put on, and a sufficient quantity of fresh, FORCING FRAME, that kind of large frame- hot, stable dung, prepared as for common work or erection which is made use of in pro- dung hot beds, is to be piled up close against curing different sorts of vegetables, fruits, and the outside of the back and ends, a yard wide flowers at an early period, by the application of at bottom, drawing it gradually into a foot artificial heat in some of the above modes. width at top, finishing it somewhat sloping, to It is a construction covered with sloping throw off wet; and as the dung settles or sinks glass sliding frames on the top, and sometimes down, a fresh supply must be added at top, to in the front. It may be either fixed or move- maintain the lining to the full height of the able; but in the former case the walls are most. frame, additions being occasionally made of ly made of brick-work.

fresh dung, as the heat declines ; by this These sorts of forcing frames are usually means a fine growing heat will be thrown in. placed full to the south sun, and the length See HoT BED. may be from ten to fifty, or one hundred feet; Where bark is made use of in producing the width from five to fifteen, and from five to heat, the frame may be constructed either of ten high; having an upright back wall of wood or brick work, and fronted, &c. with wood, where small, but where large, of brick; sashes of glass as the former; the length may and a front of glass-work, made sometimes in be ten, twenty, or thirty feet, or more ; eight one continued range of slope to the top of the or ten wide, and six or eight high; and, þack wall; and sometimes with upright glass- like the dung heat frame, be six or eight feet work, head high, ranging immediately along high behind, and one in front, the ends conthe front, and from the top of which a glass formable and sloping, having glass work frames roof is carried to the top of the back or main raised from the front, sloping either quite 10 wall: when wrought by dung heat, it is chief- the top of the back wall, or inclined only about ly applied against the outside of the back wall, one half towards that part, meeting a tiled roof and by being formed into a bed internally; at top half way, which should be raised high when by bark heat, by forming it into a bed in enough in front to throw the water off behind, a pit within side; and when by fire heat, by as well as to admit as much sun as possible to having several returns of Aues against the in- every part of the frame; it may likewise be side of the back wall, and that of the front and constructed with an upright front of glass, head both ends, for the heat to pass along, con- high, and a sloping roof of glass work, ranging structed according to the sorts of plants chiefly from the upright front to the top of the back intended to be forced, and the nature of the wall, which is the most eligible form, both for materials to be employed in producing the convenience and benefit of the plants ; cither of heat.

which constructions may be erected detached, Where the first kind of materials is employed or against a south wall already built, which will in affording heat, the frame is usually formed serve for the back, and save some expense; the with an upright back and ends of deal planking, ends may either be of wood or brick, and should and a sloping front of moveable glass lights ; be glazed like the front, &c. and the glass work the length may be ten, twenty, or thirty feet, in every part be made to move on and off, as or more; the width from three to five (or well as to slide backward and forward, to give more), and five or six high; the frame-work air, and perform other necessary work. At one should be of inch and half deal planking, end, near the back wall, a 'door should be tongued, and closely joined, that no steam from made to enter occasionally at, and withinside,

a pit formed for the bark bed, three feet deep, be seen in the plates on forcing frames, họt part sunk, the greater part raised, continued houses, &c. the whole length and width, except about a In the first description of forcing frame, vafoot and half alley to pass in to perforin the ne- rious kinds of fruits may be produced both of cessary culture, as well as view and gather the the dwarf fruit tree, and other sorts, as well procuce of the different plants.

as different sorts of vegetables and plants of the The pit within is to be filled with new tan, flowery and other kinds. in order to afford a proper heat for the growth Frames of this sort may have such dimenand support of the plants that are to be culti- sions as to have substantial hot beds prepared väter. See HOT BED.

within them, for the purpose of receiving many Where fire heat is to be employed, the frame different sorts of potted plants. must be formed of brick work, at least the back And in the second sort of frame, from the or main wall, for the convenience of having heat being more regular and lasting, a still Sre fues, and the whole front, &c. be glass greater variety of the finer sorts of fruits, and like the other sorts; the length may be from the more tender flowers and other vegetable iwenty to forty or fifty feet, or more, though productions, may be produced, not only long one fire will not warm more than that length; before they could be raised in any

other

way, the width from five or six to twelve or fiftcen but with much greater ease and convenience, feet, and eight or ten high. In this case the as well as with greater certainty. fire is burned in a furnace behind, at one end The last kind of forcing frame is employed or middle, thence communicating the heat by in furnishing many of the finer sorts of fruits, internal fines or funnels running the whole that require high degrees of heat to produce length of the back wall, in three or four returns them in the utmost perfection, such as pineone above another, and continued in one or apples, grapes, apricots, peaches, nectarines, two flues in the front. And frames thus con- and various others, as well as many tender soris structed may be contrived either of moderate of vegetables, and numerous plants of the cuwidth, for one row of trees only, to range rious Hower and other kinds. against the back wall, or may be capacious FORCING GROUND, the portion of ground enough to have a range of trained wall trees be- in a garden that is destined to the purpose of hind, and some small half or full standards, forcing or raising vegetable productions by ranging also from the back to the front, or means of artificial heat. Grounds of this sort entirely for standards, especially those of cher- should always be detached from the garden, sies.

and situated as near to the stable as the nature Where it is intended to have a narrow frame of the land will admit, in order that dung may for only a row of trained trees behind, the be conveyed to them with as much ease and width of from four to five or six feet is suffi- couvenience as possible, litter prevented, and ciest, having the back or main wall formed of the disagreeable' appearance of the beds conbrick or stone, as just observed, eight or ten cealed. feet high, with several Alues withinside, re- It is necessary in most situations, and partiturned over each other, running the whole cularly in such as are exposed, to have them length of the wall; in the front must be a low inclosed with a fence, either of brick work or wall a foot high, on which to lay a plate of paling, six or eight feet in height. They imber, and from which are ranged glass frames should have sufficient space for containing a or lights in one continued slope to the top of suitable number of frames and pits, and such the back wall, there received into proper frame linings as may be necessary in the working of work; but, for the greater convenience, the them. And it is of great advantage in raising lights may be in two tiers or ranges, an under many sorts of tender crops, both of the vegetaand upper tier, the upper range made to slide ble and fruit kind, to have four or six feet borup and down over the others, but so that all the ders made round them in a raised manner. glass work can be mored away occasionally, to Where melons are raised, it is usual to havo admit the full air w the trees after the work of brick pits coped with stone or wood. Those forcing is over: the whole bottom space within which are most convenient, according to Mr. the frame should be of good loamy earth, or Forsyth, are such as are about twelve feet in any good garden mould, two spades deep, width, and two and a half in depth; the length which should be dug or trenched in the com- in proportion to the number of frames employinon way; then a range of trees planted be- ed. They are, however, often made of much hind, towards the wall, two or three yards smaller dimensions, especially where the asunder, erecting a trellis behind them, upon extent of forcing ground is but small. which to train the branches, as against a wall In regard to the size of the lights for early or espalier. Other inferior plants may likewise melons, the above author advises, that they he set in the border, or in pots, in front of the should be five feet in length, and three trees.

in breadth; and for others six feet in Io forcing frames of this construction, from length, and four in breadth, the former being forty or fifty feet long may be sufficient; but four, and the latter three light boxes. Sce if longer, two furnaces for fires are necessary.

FRAME. See HOT HOUSE.

In constructing the pits, nine inch walls Different sorts of frames of this nature may will be sufficient, square spaces of wood being

built in the upper parts of them, where wood nuscript in vellum of this historian is in the copings are made use of, to nail them to. As library of the university of Edinburgh. wood decays rapidly, stone should be preferred. FORDWICH, a member of the town and Sometimes the walls are not built solid, but port of Sandwich in Kent, seated on the river square openings left, so as to admit the heat Stour, and governed by a mayor, jurats, and froin the outsides.

commonalty. It is noted for its excellent Mr. Forsyth directs, that there “ should be a trouts, and lies three miles N. E. of Canterwalk between the ridges, about six or seven bury. feet broad, sufficient to admit a cart to carry

FORDYCE (David), an ingenious writer,

, dang," as being more expeditious than wheel. born at Aberdeen in 1720. He was educated ing it in.

at that university, and became professor of The wak should be made up as high as the moral philosophy in the Mareschal college. On roping, and sloping gently towards each end," his return to England from a tour through sebeing laid in the bottom with brick rubbish, veral parts of Europe, he was shipwrecked and and covered over with sea coal ashes or sand. drowned in 1751. He wrote ; 1. Dialogues By this means, after the linings are made up, it concerning Education, 2 vols. 8vo. 2. A may be kept perfectly neat and clean. A loose Treatise of moral Philosophy in Dodsley's Predrain will'likewise be necessary in the middle ceptor. 3. Theodorus, a Dialogue, concernof the bottom of the pit, for conveying off wèt ing the Art of Preaching. and the oozing from the dung, to a tank_or FORDYCE (Dr. James), a noted divine, was cistern constructed for its reception. The brother of the preceding, and born also at fluid thus collected may be made use of in Aberdeen in the same year : he was educated watering cabbage and other plants of the same at that university. Early in life he was settled kind.

minister of the parish of Brechin, and became FORCING PIT, a sort of pit constructed very celebrated as a preacher. After a few years of brick work, with fire Aues, in various he received a presentation to the church of Always, for the purpose of making tan or loa, near Stirling. About the year 1760 he other hot beds in, being covered with glass preached before the General Assembly of the frames.

Church of Scotland, a fine sermon on the It is useful for receiving different sorts of ten- folly, infamy, and misery, of unlawful pleader potted plants which require considerable sure, which raised his fanie as a pulpit orator so degrees of heat in their cultivation.

high, that the university of Glasgow soon after FORCING WALL, a wall constructed with sent him a diploma, creating him D. D.; and, Alues for the purpose of conveying and commu- which was more extraordinary, he received an nicating fire heat, in order to ripen various invitation from a very respectable congregation kinds of tree fruits that are planted and train- of protestant dissenters, meeting in Monkwelled against them, and which are protected street, London ; this invitation he accepted. in the front by glazed frames.

About 13 years previous to his death, the docWalls of this sort should always be erected tor's ill health obliged him to resign this charge ; in warm sheltered situations, and have southern and he retired to a village in Hampshire. He aspects, in order that they may derive the died at Bath, Oct. 1. 1796. His most noted greatest possible advantage from the influence works are, Sermons to Young Women, 2. vols. of the sun.

Addresses to Young Men, 2 rols. and AdFOʻRCIPATED. a. (from forceps.) Form- dresses to the Deity, 1 vol. His Sermons to ed like a pair of pincers to open and enclose young women have attracted most general no(Derham).

tice; but, for our own part, we do not perceive FORD. s. (fond, Saxon.) 1. A shallow in them many excellencies. Had we been so forpart of a river where it may be passed without tunate as to hear them from the pulpit, we congwimming (Fairfax). 2. The stream ; the clude we must have admired them, for Dr. Forcurrent (Milton).

dyce was qualified to excel as a preacher. The To FORD. v. a. (from the noun.) To pass effectof his pulpitaddresses was much heightenwithout swimming (Raleigh).

ed, not only by an action and an elocution, FO'RDABLE. a. (from ford.) Passable which he studied with care and practised with without swimming (Raleigh).

success; but by the figure of his person, which FORDINGBRIDGE, a town in Hamp- was peculiarly dignified, and by the expression of shire, with a market on Saturdays. Lat. 50. his countenance, which was animated at all 56 N. Lon. 1. 49 W.

times, but animated most of all when lighted up FORDOUN (John of), the father of Scot- by the ardor of his soul in the service of God, By tish history, flourished in the reign of Alexan- some of his hearers, it was observed that, on der III. towards the end of the 13th century. many occasions, he seemed not merely to speak, But of his life there is nothing known with but to look conviction to the heart. His eye, certainty, though there was not a monastery indeed, was particularly bright and penetrating, that possessed not copies of his work. The and he had carefully attended to the effect first five books of the history which bears his which an orator may often produce upon aa name were written by him : the rest were fa- audience by the judicious use of that little, bricated from materials left by him, and from but invaluable organ. new collections by different persons. A ma- FORE, a. (fore, Saxon.) 1. Anteriour;

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