Units

Make thee an ark of gopher wood; roomsshalt thou make in the ark; and shall pitchit within and without with pitch.

And this is the fashion which thou shaltmake it of; the length of the ark shall bethree hundred, the breadth of it fifty, andthe height of it thirty.

Genesis 6: 14-15

Unit of Length Used in Genesis

The length of your forearm.Cubit

First recorded unit of length.

Egyptian Cubit RuleLiverpool Museum

Town Hall of Laon, France

“T” for the Size of Barrels

Ell for Cloth

Gauge for Bricks

Gauge for Roof Tiles

Leviticus

Ye shall do no unrighteousness in judgment, in meteyard, in weight, or in measure.Just balances, just weights, a just ephah, and just hin, shall ye have.

Unit Stnds Established in the Magna Carta

Agreed to by King John of EnglandRunnymede, 1215

Clause 35

There shall be one measure of wine throughout our whole realm,and one measure of ale and one measure of corn -- namely, the London quart, and one width of dyed and russet and hauberk cloths-- namely, two ells below the selvage.

(a textile’s selvage)

London Quart

Ell = a yard and a quarter

Unit Stnds Established in the US Constitution

Section 8… fix the Standard of Weights and Measures; …

Origin of the Metric System - 1790French National Assembly requests the French Academy of Sciences to

…deduce an invariable standard for all the measures and all the weights.

Charles de Talleyrand-PérigordIn place of a measure derived from history or the fiat of kings,he asked that the legislature derive its fundamental measurefrom nature, the common heritage of all mankind. Only a measurederived from nature, he declared, could be eternal because onlysuch a standard could be reconstructed should its man-madeembodiment suffer the ravages of time.

The Measure of All ThingsKen Adler

1790 meter ProposalOne Millionth of the Distance Between the Pole and the Equator along a Meridian running through Paris

1793 Provisional meter

1799 meterThe final step was to embody the meter in a permanent physical standard. Copper had been sufficient for the provisional meter, but for the definitive meter only ultimate metal would do. Long despised as a contaminant by South American prospectors, Platinum was difficult to melt, difficult to purify, and nearly indestructable. For justthat reason it had acquired a lustrous reputation among savants. It promised to outlast time. … The Commission of Weights and Measures spent one fifth of its budget buying and refining some one hundred pounds of pure platinum.

In April 1799 [Lenoir] was supplied with the calculated value of the definitive meter and four bars of pure platinum, and told to shape four standards of precisely one meter each. For this purpose he employed a “comparator” of his own invention, which could gauge objects to within one millionth of a toise (0.0000072 inches). The task was “diabolically tricky.” Of the four bars, the one that came closest – within0.001 percent of the proper length – was selected as the definitive meter. The Measure of All Things

Ken Adler

“Convention of the meter” - 187515 years later the meter was forged.Made of a Platinum-Iridium Alloy.

1963 Meter

Krypton Gas Discharge1,650,763.73 wavelengths of orange-red light, in a vacuum, produced by burning the element Kr-86.

1983 Meter

Distance light travels, in a vacuum, in 1/299.792,458 seconds.

Mass -Kilogram Time - Second

Temperature - Kelvin

Amount - Mole

Metric Prefixes

peta P 10+15

tera T 10+12

giga G 10+9

mega M 10+6

kilo k 10+3

hecto h 10+2

deca da 10+1

deci d 10-1

centi c 10-2

milli m 10-3

micro m 10-6

nano n 10-9

pico p 10-12

femto f 10-15

Length Mass Temperature1 in = 2.54 cm 1 kg = 2.2046 lb K = oC + 273.151 mi = 5280 ft 1 lb = 16 oz oC = (oF - 32)1 ft = 12 in 1 amu = 1.6605 x 10-24 kg oF = oC + 321 yd = 3 ft1 cubit = 18 in1 ell = 45 in Volume Energy Pressure1 L = 10-3 m3 1 cal = 4.184 J 1 atm = 101325 Pa1 L = 1.0567 qt 1 eV = 1.602 x 10-19J 1 atm = 760 Torr = 760 mmHg1 gal = 4 qt 1 bar = 105 Pa1 qt = 2 pt 1 J = 1 kg m2/s2 1 psi = 6894.757 Pa1 pt = 16 oz1 mL = 1 cm3 1 Pa = 1 N/m2 = 1kg/m s2