MAMMOTH RANGE FINDER.

Hawera & Normanby Star, Volume XLII, Issue XLII, 23 March 1922, Page 3

MAMMOTH RANGE FINDER.

DISTANCE OF OBJECT UP TO TWENTY-TWO MILES. The latest scientific wonder is a mammoth, range finder, which is capable of accurately judging the distance of any object up"to 22 miles away. It is three times the size of any used during the war 3 and it is the biggest of its kind in the worjd. Tojook at the instrument is a metal tube, 100 feet long, mounted on a carriage which swings round on a circular track in much the same way as a railway turntable. In the centre of the tube is a control chamber containing intricate adjusting machinery, which is worked by the observers. By means of reflectors at the ends of the tube the observer can see through an eyepiece the distant object. While the view process is complicated to describe, it may be pointed out that the instrument works- on the well known principle that if the eyes 1 look , straight outwards towards a distant I object, and are gradually turned, inwards as the object approaches, if the angle through which the eyes turned could be measured it would be possible to estimate the distance of the object. In fact, this movement is made by a prism which may be moved along the tube by an operator, and reports the distance at the same time.