## Post Office Precision

The United States post office must use the most sensitive scale in the world.

I thought that a package I mailed weighed 13 pounds. I was mistaken. It only weighed 10 pounds and 4.960000000000008 ounces.

Does that equal eight trillionth of an ounce, or 800 quadrillionth? A pico ounce or a femto ounce?

## Useful Information, Chart 5

Product: Tops Marble Composition Book, 7.5 X 9.75 Inches, College Rule, 100 Sheets, White (63796)

Sold by: Tops Products

Cost: out of stock everywhere

I saw this composition book for sale for \$8.00. Crazy right? Except this chart really does happen to have Useful Information. It has fractions (and decimals and percents). And temperature conversion. And is written in clear English. For example, under Metric Unit Conversion, the column reads “When You Know: ________ Multiply By: ________ To Find: ________”.

What I do not see are roods (square measure), scruples (Apothecaries’ weight), reams (paper measure), grains (troy weight), or knots (miscellaneous measures). It is also the only chart to include “mass.”

Hidden Highlights

• 1 hectare = 2.471 acres
• To write a decimal for a percent, move the decimal point two places to the left. Omit the percent sign;
• To convert Celsius to Fahrenheit: mutiply by 9, divide by 5 and then add 32.

Categories

Metric Unit Conversions (Length and Distance; Surface or Area; Volume and Capacity [Liquid]; Weight and Mass; Termperature)

Fractions

Decimals and Percents

Multiplication Chart

## Useful Information, Chart 4

Product: Staples Graph Composition Book, 9.75 X 7.5 Graph Paper Notebook, Black (not marbled – ed)

Sold by: Staples

cost: \$2.00

This Useful Information chart is on the inside back cover of a graph paper composition notebook. The cover is not the typical marble design. Right away I see some cool icons and graphics…the other Useful Information charts 1-3 have only text. Also, this one has a 3-inch ruler! The content is much the same as chart 2.

Hidden Highlights

• an acre measures ~209 feet on each side
• A perch of stone is 16 1/2 feet long, by 1 1/2 feet wide, by 1 foot high. (I would call this a low wall, but what do I know?)

Categories

Conversion Tables (length, capacity, weight; metric to American standard)

Multiplication Table

Table of Time Measure

Table of Dry Measure

Table of Liquid Measure

Table of Paper Measure

Table of Linear Measure

Miscellaneous Measures

Table of Cubic Measure

Table of Avoirdupois Weight (pounds and ounces: what we use in America)

Table of Troy Weight (for gold, silver, precious metals)

Table of Circular Measure

Table of Apothecariesâ€™ Weight (for medicines)

Table of Surface Measure (as opposed to Square measure)

## Useful Information, Chart 2

Product: School Smart Hard Cover Marbleback Composition Book

Sold by: Walmart

Cost: \$1.87

This is the inside back cover of the composition book. There is another Useful Information chart on the outside cover of this notebook, with different information. It appears as if it was written by a different author.

Hidden Highlights:

• Table of Paper Measure (24 sheets = 1 quire);
• Miles in a Township (36 square);
• Miscellaneous Measures (a bushel of potatoes = 60 lbs)

Categories

Conversion Tables (length, capacity, weight; metric to American standard)

Multiplication Table

Table of Time Measure

Table of Dry Measure

Table of Liquid Measure

Table of Paper Measure

Table of Linear Measure

Miscellaneous Measures

Table of Cubic Measure

Table of Avoirdupois Weight (pounds and ounces: what we use in America)

Table of Troy Weight (for gold, silver, precious metals)

Table of Circular Measure

Table of Apothecaries’ Weight (for medicines)

Table of Surface Measure (as opposed to Square Measure)

## Useful Information, Chart 1

Product: School Smart Hard Cover Marbleback Composition Book

Sold by Walmart for \$1.87

This chart is on the outside back cover. What is interesting is that the book has another Useful Information chart on the inside back cover, just in case one wasn’t enough. I would guess that about 90% of the information is the same in both charts, though there are differences. You may notice that there are no metric-to-metric or metric-to-U.S. standard conversion tables.

Hidden Highlights:

• A cord of wood is equivelent to a pile 8 feet long, 4 feet wide, and 4 feet high;
• 6 feet = 1 fathom;
• 1 acre = 160 square rods;
• 40 square rods (i.e., 1/4 acre) = 1 rood; therefore
• 1 acre = 4 roods

Categories

Liquid Measure

Cubic Measure

Avoirdupois Weight

Miscellaneous

Square Measure (as opposed to Surface Measure)

Linear Measure

Circular Measure

Apothecaries’ Fluid Measure

Multiplication Table