As the number of digits (0) is _even_, the cursor is set to 149 on the
right-hand scale of A, giving 386 on D. By the rule, the number of
digits in the root will be (0)/(2) = 0, and the root will be read as
0·386 [0·38605+].
Another method of extracting the square root, by which more accurate
readings may generally be obtained, is by using the C and D scales only,
with the slide inverted. If there is an _odd_ number of digits in the
number, the _right_ index, or if an even number of digits the _left_
index, of the inverted scale Ɔ is placed so as to coincide with the
number on D of which the root is sought. Then with the cursor, the
number is found on D which coincides with the same number on Ɔ, which
number is the root sought.