Bingham News | 1922-11-25 | Page 5 | Invention Tests Air

Invention Tests Air. The Paris-London air service has an Ingenious Instrument for measuring measur-ing the depth of fog above the starting start-ing place at Croydon or Abbeville, and so to determine whether there Is clear, dry weather a few hundred feet up. The instrument, which Is based on the property of human hair of contracting con-tracting sharply on passing from wet to dry air, consists of a hair attached to a trigger that holds a ring. The Instrument is sent aloft with toy balloons bal-loons on a string; as soon as It reaches dry air the hair contracts, pulls the trigger, and down conies the ring on the string. Youth's Companion.