. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . r-platemuft alfo be fet right by means of a pin ; and the fniall-nefs of the teeth in the pendulum-wheel will caufe thependulum ball to defcribe but fmall arcs in its vibra-tions ; and therefore the momentum of the ball will belefs, and the times of the vibrations will be more affec-ted by any unequal inipulfe of the pendulum-wheel onthe palettes. Befides, the weight of the flat ring on
. Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . r-platemuft alfo be fet right by means of a pin ; and the fniall-nefs of the teeth in the pendulum-wheel will caufe thependulum ball to defcribe but fmall arcs in its vibra-tions ; and therefore the momentum of the ball will belefs, and the times of the vibrations will be more affec-ted by any unequal inipulfe of the pendulum-wheel onthe palettes. Befides, the weight of the flat ring onwhich the feconds are engraved will load the pivots of• the axis of the pendulum-wheel wiih a great deal offriclion, which ought by all poflible means to be avoid-ed. To remedy this inconvenience, the fecond platemight be omitted. A clock fimilar to Dr Franklins was made in Lin-colnflire about the end of laft century or beginning ofthis ; and is now in London in the polfeiTion of agrandfon of the perfou who made it. A clock, fiiowing the apparent diurnal motions ofthe fun and moon, the age and phafes of the moon,?with the timeof her coming to the meridian, and the times riock. c:i,()(K C L O [ V C L O CIocV. times of high and low water, by having only two* ^ • wheels and a pinion added to the common movement,was contrived by Mr Fcrgulon, and dcfcribed in his Se-Plat«CLX. ledExercilcs. The dial-pluie oithis clock (iig 7.) con-tains all the twenty-fonr hours otthe day and night. S isthe fan, which ferves as an hoarindcx, by going roundthe dial-plate in twenty-four hours ; and M is the moon,which goes round in twenty-fourhours JiityminutCb anda half, the time of her going round in the heavens fromone meridian to the fame meridian again. The fun isfixed to a circular plate (fee fig. i.), and carried roundby the motion of that plate on which the twenty-fourhours are engraven ; and within them is a circle divi-ded into twenty-nine and a half equal pares for the da
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Keywords: ., bookcentury1700, bookdecade1790, booksubjectencyclo, bookyear1798
