For your northern boundary, run a line from the Great Sea to Mount hor.
Take Aaron and Eleazar his son, and bring them up unto mount hor.
And this shall be your north border: from the great sea ye shall point out for you mount hor.
SO, the formulas of BHA's critical load and critical length were deduced and given by the hor to fit in with the BHA's loading features as well as to improve the calculating exactness.
