Volume 2

A mathematical and philosophical dictionary: containing an explanation of the terms, and an account of the several subjects, comprized under the heads mathematics, astronomy, and philosophy both natural and experimental: with an historical account of the rise, progress, and present state of these sciences: also memoirs of the lives and writings of the most eminent authors. Both ancient and modern, who by their discoveries or improvements have contributed to the advancement of them ... With many cuts and copper-plates / By Charles Hutton.

  • Hutton, Charles, 1737-1823.
Date:
1795-1796
Catalogue details

Licence: Public Domain Mark

Credit: A mathematical and philosophical dictionary: containing an explanation of the terms, and an account of the several subjects, comprized under the heads mathematics, astronomy, and philosophy both natural and experimental: with an historical account of the rise, progress, and present state of these sciences: also memoirs of the lives and writings of the most eminent authors. Both ancient and modern, who by their discoveries or improvements have contributed to the advancement of them ... With many cuts and copper-plates / By Charles Hutton. Source: Wellcome Collection.

    138/818 (page 130)
    Movement, in its popular ufo, fignifies all the inner works of a clock, watch, or other machine, that move, and by that motion carry on the defigii of the inllru- ment. The Movement of a clock, or watch, is the infide; or that part which meafiires the time, and ftrikes, &c ; exclufive of the frame, cafe, dial-plate, &c. The parts common to both of thefe Movements are, the Main-fpring with its appurtenances,^ lying m the fpring box, and in the middle of it lapping about the fpring-arbor, to which one end of it is fattened. A-top of the fpring-arbor is the Endlefs fcrew, and its wheel; but in fpring clocks this is a ratchet-wheel with its click, that ttops it. That which the ^ main-fpring draws, and round which the chain or firing is wrap- ped, is called the fufee : this is moftly taper ; in large works, goitig with weights, it is cylindrical, and is called the barrel. The fmall teeth at the bottom of the fufee or barrel, which ftop it in winding up, is called the Ratchet ; and that which ttops it when wound up, and is for that end driven up by the fpring, the Garde- ♦^ut. The Wheels are various : the parts of a wheel are, the Hoop or Rim ; the Teeth, the Crofs, and the Collet, or piece of brafs foldered on the arbor or fpindle on which the wheel is riveted. The little wheels, playing in the teeth of the larger, are called Pinions ; and their teeth, which are 4, 5,6, 8, &c, are called X^eves ; the ends of the fpindle are called Pivots ; and the giittured wheel, with iron fpikes at bottom, in which the line of common clocks runs, the Pulley. theory of Calculating the Numbers for Movements. 1. It is firft to be obferved, that a wheel, divided by its pinion, fhews how many turns the pinion has to cue turn of the wheel. 2. That from the fufee to the balance the wheels drive the pinions, confequently the pinions run fatter, or make more revolutions, chan the wheel ; but it is the contrary from the great wheel to the dial-wheel. 3. That the w^heels and pinions are written down either as vulgar fradlions, or in the way of divilion in common arithmetic : for example, a wheel of 60, mov- ing a pinion of 5, Is fet down either thus thus 5)60, which is better. And the number of turns the pinion has in one turn of the wheel, as a quotient, thus 60 (12. A whole Movement may be wTitten as follows : 4) 36 ( 9 5 ) 55 5 ) 45 ( 9' 5) 40 ( 8 17 where the uppermoft number exprettes the pinion of report 4, the dial-wheel 36, and the turns of the pinion 9 ; the fecond, the pinion and great wdreel ; the third, the fecond wttiecl &c ; tlie fourth, the con- trate wheel; and the laft, 17, the crown-wheel. 4. Hence, from the number of turns any pinion Brakes, in one turn of the wheel it works in, may be determined the number of turns a wheel or pinion has at any greater dillance, viz, by multiplying the quo- tients together ; the product being the number of turns. Thus, fuppofe the wheels and pinions as in the cafe above-; the quetient is. multiplied by 9, gms 99, the number of turns in the fecond pinion 5 to one turn ^ the wheel 55, which runs concentrical, or on the farnf fpindle, with the pinion 5. Again, 99 multiplied by 8, gives 792, tbe number of turns the laft pinion has to one turn of the firft wReel 5. Hence we proceed to find, not only the turns, but the number of beats of the balance, qn the time of thofe turns. For, having found the number of turns the crown-wheel has in one turn of the wheel propofed, thofe turns multiplied by its notches, give half the number of beats in that one turn of the wheel. Suppofe, for example, the crowii- wdieel to have 720 turns, to one of the firft wReel ; this number multiplied by 15, the notches in the crown- wReel, produces 10800, half the number of ftrokes of the balance in one turn of the firft wheel of 80 teeth. The general divifion of a Movement is, into the clock, aiH watch parts. MOULDINGS, in Architecture, are certain pro- jections beyond the naked of a w^all, cdlumn, wainfeot &c, the aftemblage of which forms cornices, door-cafes, and other decorations of architeCfurc. Mouldings, are annexed to great guns by way of oriMiinent, and perhaps in fome parts for ttrength ; and probably are derived from the hoops or rings which bound the long iron bars together, anciently ufed in making cannon. MOYNEAU. See Moineau. MULLER (John), commonly called Regiomon- tanus, from Mons Regius, or Koningfberg, a town in Franconia, where he was born in 1436, and became the greateft aftronomer and mathematician of his time. Lie was indeed a very prodigy for genius and learning. Having firft acquired grammatical learning in his own country, he was admitted, while yet a boy, into the academy at Leipfic, where he formed a ftrong attach- ment to the mathematical fciences, arithmetic, geome- try, aftronomy, See. But not finding proper affiftance in thefe ftudies at this place, he removed, at only 15 years of age, to Vienna, to ftudy under the famous Piirbach, the profeflbr there, who read leCtures in thofe fciences with the higlieft reputation. A ftrong and affectionate friendftiip foon took place between thefe two, and our author made Rich rapid improvement in the fciences, that he was able to be aflifting to his matter, and to become his companion in all his labours. In this manner they fpent about ten years, together ; elucidating obfeurities, obferving the motions of the heavenly bodies, and comparing and corre6fing the tables of them ; particularly thofe of Mars, which they found to difagree with the motions, fometimes as much as two degrees. About this time there arrived at Vienna the cardinal Beftarion, who came to negociate fome affairs for the pope ; who, being a lover of aftronomy, foon formed an acquaintance with Purbach and Regiomontanus. He had begun to form a Latin Verfion of Ptolomy’s Almageft, or an Epitome of it; but not having time to go on with it himfelf, he requefted Purbach to complete the work, and for that purpofe to return with him into Italy, to make himfelf matter of the Greek tongue, which he was as yet unacquainted with. To thefe propofals Purbach only affented, on condition that Regiomontanus would accompany him, and ffiare in all the labours. They firft however, by I means