A bit more clarification on the values of the divisors:
The top level grid squares are 20 degrees longitude by 10 degrees latitude, so
? the 2000000 used as divisor in the MH[0] calculation is equivalent to dividing by 20 degrees in the scaled
? representation,and
? the 1000000 divisor is equivalent to dividing by 10 degrees for MH[1],
The next level finer grid is composed of squares that are 2 deg longitude by 1 deg latitude
? a 200000 divisor is equivalent to dividing by 2 degrees for MH[2], and
? a 100000 divisor is equivalent to dividing by 1 degree for MH[3]
The next finer squares for the third subdivision are 5 minutes longitude by 2.5 degrees latitude
? 8333 is equivalent to dividing by 0.08333 degrees or 5 minutes for MH[4]
? 4167 is approximately equivalent to dividing by 0.04666 degrees or 12.5 minutes for MH[5]
? (although I think it would be more accurate and correct to use 4167)
and finally, the next and finest grid is composed of squares that are 30 seconds longitude by 15 seconds latitude, so
? 833 is equivalent to dividing by 0.00833 degrees or 30 seconds, and
? 416 (which should perhaps be 417) is equivalent to dividing by .00416 degrees or 15 seconds
