(b) The vernier scale (3) is divided into 25 parts and numbered 0,

5, 10, 15, 20, and 25. These 25 parts are equal to 24 parts on the steel or

main rule (1). The difference between the width of one of the 25 spaces on

the vernier scale and one of the 24 spaces on the main rule (1) is 1/1000

(0.001) of an inch.

(c) Read the measurement in figure 45 on the previous page as

illustrated below:

Read the number of whole

inches on the top scale (1) to

the left of the vernier zero

index (4) and record ................. 1.000 inch

Read the number of tenths (5)

to the left of the vernier

zero index (4) and record ............ 0.400 inch

Read the number of twenty-fifths (6)

between the tenths mark (5) and

the zero index (4)

and record........................... 3 X .025 = .075 inch

Read the highest line on the

vernier scale (3) which lines up

with a line on the top scale (7)

and record. (Remember 1/25 = .001

inch) ............................... 11/25 or 0.011 inch

TOTAL

1.486 inches

the other side. If a scale isn't marked, and an inside measurement is to be

taken, read the scale as you would for an outside diameter. Then add the

measuring point allowance by referring to manufacturer's instructions or the

following table.

(e) *Reading a Metric Caliper *(figure 46 on the following page).

The same principle is applied in