(3) Quick method. This method uses a gamma meter (will be explained later). The arrow point

of the meter is placed on the straight line portion of the curve, with the baseline of the meter parallel to

the log E axis. Gamma is indicated where the straight line intersects the scale.

(4) Simplified method. A point is selected on the straight line portion of the characteristic curve

at one of the minimum densities. From this point, count over 50 spaces in a horizontal direction. Next,

count the number of spaces in a vertical direction until the straight line portion of the characteristic

curve is intersected. Multiply this figure by 2 and divide by 100. For example, if 40 spaces are counted,

the calculations are as follows: