38   Measurement of distance

In the measurement of any distance:

(a)  for the purposes of any Act passed before the commencement of this Act, or any instrument made under such an Act, the distance shall be measured according to the nearest route ordinarily used in travelling, and

(b)  for the purposes of any Act passed after the commencement of this Act, or any instrument made under such an Act, the distance shall be measured in a straight line on a horizontal plane.