( 559 )

ät Qj and on the conträry, let it Sink to 40°. 5 y 0 . (3 c. its Power upon thePoint V, will still be Diminifhed, insomuch that in T, it will be utterly extin-guilh’d. And therefore if P, be of a competent Weight (/. c not utterlyroo light) to Move the Train at all, it will certainly Move it in some Degeeeof Elevation or other in the Quadrant QT.

x. If the Weight P, be considered as to its Office of being a Counter-poife to the Body of the Movement ; as I need not to prove, that it will per-form this no lefs, while it hangs by upon the VcFUs M P, than if it wercfast Rivetted in the fame place to the Cafe of the Movement: so, in whatPoint of the Quadrant soever it will move the Train, it may be also aCounterpoise to the Body of the Movcmcnt. For,

1. At what Point soever of the Circle L E T Q,, the Line of DcclivityD E, makes an Angle of Contact; on the fame Point will the DiameterS D, fall at Right Angles with D E.

1. The Line of Dircction LD, will ever fall upon the Point of Con-ract D, making an Angle with the Diameter, as S D L.

z. The Angle S D L,will be always equal to D E H e. As great as is theElevation of the Line of Dcclivity D E, above the Horizontal EH, so greatwill the Angle of Distance be between the Diameter S D, and the Lina ofDirection L D.

4. The Greater the Angle of Dcclivity is, the Lefs will be the SectionL QD ; and so on the conträry, the Lefs that Angle is, the Greater the Se-ction. And therefore,

5- The Excefs of the Weight of LED, above L Q_D, must be alsoGreater, by Raising up the Stage with the Skrew at 8 : and that Excefs Lefsby Skresvtng it down.

6. The Lighter that part of the Body is, which is reprefented by the Se-ction LQD, the mors Heavy ought the Counterpoise P, to be ; and thateither in its öwn Intrinsick Weight, (in Ounces and Parts of Ounces) or elfein its Potential Weight, by being Raised Higher in the Quadrant Q_T.

7. The Skrewing up the Stage of the Movement at S, will Raife the Coun-terpoise Higher in the Quadrant QT, by Prop. z. and therefore PotentiallyHeavier. And from hence appears, (l take it most clearly) both the reasonof the due Adjustment of the Motion of the Train to the exact Meafure ofan Hour, and what Weight is to be aflign’d to P, that Moves it; and that,we are not confined to Scruples and Grains, but are allowed soch a conüdera-ble latitude, as it is not eaiie to err therein.

Having therefore sot the Stage (by the lielp of the Arched Skrew) at theElevation of about xo Deg. place the Movcmcnt thereon, and try what Weight,hanging at the end of the VcBis MP, will stir the Train, mean whileholding the Movement with the Hand in such a Position, as the Ve Bis -maymake an Angle of about 30 Deg. with the Perpendicular M T : then letthe Movement loofe, to Undulate upon the Stage ; and when the Vibrationceafes, obferveto what Degree of the Quadrant the Veclis Points, and at the'fame time mind the Pulses of the Ballance. If at this Obfervation, theWeight. lies low, (as for instance, between ay and 35 Deg. of the Quadrant)