This document discusses early systems of measurement like cubits, fathoms, hands, and paces based on human anatomy. It then summarizes that by the late 1700s, dozens of inconsistent measurement units caused confusion in international trade. To solve this, the French government commissioned scientists to design a simple decimal system, which became the metric system introduced in 1790 and adopted by most countries by 1960 under the name Système International d'Unités.

1. Early Measurement History
to
Metric System

2. 
The Cubit . . .

The Fathom . . .

The Hand/span . . .

The Pace . . .

3. The cubit is the measure from
your elbow to the tip of your
middle finger when your arm is
extended.

4. The fathom is the
measure from
fingertip to fingertip
when your arms are
stretched sideways as
far as they will go.
You sometimes see a
rope or fabric
measured in this way.

5. The hand-span is the
measure from the tip
of your pinky to the
tip of your thumb
when your hand is
stretched out.

6. The pace
is the
measure
of
distance
from one
step to
another.

7. Enter…The Metric System
By the eighteenth century, dozens of
different units of measurement were
commonly used throughout the world.
The lack of common standards led to a lot
of confusion in trade between countries.
At the end of the century, the French
government sought to solve this problem.

8. Enter…The Metric System
In 1790, the French National Assembly
commissioned the Academy of Science to
design a simple decimal-based system of
units.
The system they devised is known as the
metric system.
In 1960, the metric system was officially
named the Système International d'Unités (or
SI for short) and is now used in nearly every
country in the world except the United States.

9. Enter…The Metric System
The metre was originally calculated
as one ten-millionth of the distance
from the North Pole to the Equator
through Paris, but it is now defined in
terms of wave length.