Stan Jacuba wrote in USMA 20547:
>Since Napoleonic times, artileries have beem aiming with the use of a
>decimal division of the right angle. Call it the mil (a thousanths of it)
>or gon, or grad, or grade, etc., (the hundreths part of it).
>That division is the oldest metric unit. It was established before the metre.
>Stan Jakuba
It is not that simple. The right angle has been expressed in several ways, viz:
90�
�/2 = 1,5708...radians
100 gon
1 570.8...milliradians
1 600 mil
Joseph B.Reid
17 Glebe Road West
Toronto M5P 1C8 Tel. 416 486-6071
