Mathematics for Carpenters and Builders - Carpenter's and Builder's Math, Plans, and Specifications - page 133

100 feet long and is graduated in feet except for the last foot, which
is divided into tenths and hundredths of a foot.
Table 5-4 shows nautical measurement equivalents.

Table 5-4 Nautical Measure (U.S. Navy)

Measure Equivalent

6 feet 1 fathom

120 fathoms 1 cable length

The International Nautical Mile ∗ 6076.1033 feet

3 nautical miles 1 marine league

∗ Adopted in 1954.

The knot is a measure of speed, not of length, and is equivalent to
1 nautical mile per hour. A speed of 16 knots is equal to 16 nautical
miles per hour.
Square Measure
Square measure is used to measure areas. In most (but not all) cases,
linear units are used to measure the two dimensions, length and
width, and their product is the area in square units. Expressed as an
equation:
length area

The two dimensions, length and width, must be measured in the
same units, but any unit of linear measurement may be used. If
inches are multiplied by inches, the result will be in square inches;
if feet are multiplied by feet, the result will be in square feet, and so
forth (see Figure 5-7).
For the small areas commonly found in everyday life (such as
tabletops or shelves), the unit most commonly used is the square
inch. Plywood and lumber are commonly sold by the square foot.
Carpets and other floor coverings and materials and ceilings are
measured in square yards. The carpenter measures roofing by the
square of 10

× width =

10 feet, or 100 square feet. Tracts of land are usually
measured in acres or, for large areas, in square miles.
Table 5-5 shows square measure equivalents.
Cubic Measure
Cubic measure is used to determine or appraise volumes. Three di-
mensions are involved (length, width, and height) and their product
is volume. Expressed as an equation:
length

×

× width × height = volume