INVESTIGATION

, the searching or finding any thing out, by means of certain steps, traces, or ways.

INVOLUTE Figure or Curve, is that which is traced out by the outer extremity of a string as it is folded or wrapped upon another figure, or as it is unwound from off it.——The Involute of a cycloid, is also a cycloid equal to the former, which was first discovered by Huygens, and by means of which he contrived to make a pendulum vibrate in the curve of a cycloid, and so theoretically at least vibrate always in equal times whether the arch of vibration were great or small, which is a property of that curve.——For the doctrine and nature of Involutes and Evolutes, see Evolute.