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Chapter 27
(without photos) of
HOW TO EUROPE
The Complete Travelers Handbook
Internet edition.
A page from
Enjoy-Europe.com
by
John Bermont
You'll have to go metric in a hurry.
AMERICAN SYSTEM
Avoirdupois
First, let's take a short refresher course on ordinary American weights and measures.
The American system is derived from the system historically
used in Britain. We use avoirdupois measures.
The smallest unit of weight in everyday use is the ounce. Next up is the pound, 16 ounces.
Then we jump to the ton, 2,000 pounds. Internationally speaking, the American ton is known
as the short ton. A hundredweight, 100 pounds, is also used in commerce.
American liquid measurements normally start with the fluid ounce, not to be confused with the
ounce used in weight measurement. Increasing quantities are the pint of 16 fluid ounces, the
quart of two pints, and the gallon of four quarts. A pint of water weighs about one pound.
Cooks also use the cup measurement of 4 ounces.
Length measurement starts with the inch, about the length of the last digit of your index finger.
Then 12 inches make a foot, three feet make a yard, and 5,280 feet make a mile.
Troy
Troy weights, named after the French city Troyes, are used for precious metals and gems. The troy
ounce is about 10% heavier than an avoirdupois ounce. But a troy pound is 18% lighter than an
avoirdupois pound. The reason for this apparent discrepancy is that there are 16 ounces in
an avoirdupois pound and only 12 ounces in a troy pound. Unless you are a jeweler you won't often
see troy weights.
BRITISH SYSTEM
The first stop for Americans is often England. There is where you'll find your first
confusion. The British formerly used the same names for weights and measures that we do but
this is now generally illegal. A British green grocer was arrested and tried for selling
bananas by the pound. He was convicted of this heinous crime and summarily punished.
Because Britain is a member of the European Union, which has decreed metric for all members,
Britain has joined the metric club with limited exceptions to the old system.
For the time being, up until 2009, road signage is still in miles and ale is still
served by the pint in British pubs. A British mile is the same distance as an American mile
but a British pint is an imperial pint, 20% larger than an American pint. A British pint has 20 imperial
ounces so you would expect that it would be 25% larger than an American pint. But, the imperial ounce
is smaller than an American ounce so the correct answer is 20%. Now you can find a trivia game
and win the weights and measures category.
Oops, the game is not over. When you buy your brew in a store it has to be in a metric container. An
imperial pint is 568.26 milliliters. If the pub pint of ale ever gets outlawed you would have to order
a five-sixty-eight-point-twenty-six. I guess the bar keep will know you've had too many when you can't
get all of that out of your mouth.
A unique British unit of weight is the stone. People weight themselves in stones, or at least they did
before they went metric. One stone is 14 pounds.
METRIC SYSTEM
Metrics in America
Most Americans have heard that the United States is converting to the metric system.
Some busy-bodies are not content with the simple units of measure that we grew up with and for various
reasons they have advocated that the USA convert to the metric system. Most of the rest of the
world has already gone metric. It was made legal in the USA in 1866 but never gained a foothold.
In recent years the metric advocates have succeeded in getting Congress to require metric units
on many products. For the past 10 years or so all product labels now have the metric equivalent of the
weight or volume in parenthesis next to the good old American way of measuring things.
For example, here I have a 20 oz (567g) can of sugar and a box of hand wipes 8 in x 12.5 in
(203.2 mm x 317.5mm). Having those metric units on the labels is just so darn practical, not.
What Is the Metric System?
The metric system is a decimal system of weights and measures in which the gram is the
unit of weight, the meter is the unit of length, and the liter is the unit of volume.
These units are conveniently related: one liter of water weighs 1,000 grams and one cubic
meter contains 1,000 liters. One cubic meter of water weighs 1,000 kilograms,
which is a metric ton, also known as a long ton.
Amounts greater or smaller than grams, meters, and liters are expressed by adding
prefixes derived from Greek and Latin words for ten, hundred, and thousand. Thus you have:
| Units |
Prefix |
Example |
| 1000 |
kilo- |
one kilogram = 1000 grams |
| 100 |
hecto- |
one hectoliter = 100 liters |
| 10 |
deca- |
one decameter = 10 meters |
| 0.1 |
deci- |
one decimeter = 1/10 meter |
| 0.01 |
centi- |
one centiliter = 1/100 liter |
| 0.001 |
milli- |
one milligram = 1/1000 gram |
Additional prefixes are available for millions and billions but you won't see those on the
store shelves, well, except in computer stores where everything is mega- and giga- these days, but
you already know that.
The centi- prefix is one of the most common you will see and always means 1/100th of
whatever. This is easy to remember because the American cent is 1/100th of a dollar. Cent shows
up in many other places as well, such as century, centipede, centurion, centigrade, and cent, the
French word for 100.
Abbreviations
We seldom write out pounds
and gallons but usually use lbs. and gals. They do the same with metric units. Here are some
common abbrs.:
| |
Weight |
Volume |
Length |
| kilo- |
kg |
kl |
km |
| hecto- |
hg |
hl |
hm |
| deka- |
dag |
dal |
dam |
| Basic Unit |
gram |
liter |
meter |
| deci- |
dg |
dl |
dm |
| centi- |
cg |
cl |
cm |
| milli- |
mg |
ml |
mm |
Using Metric
The conversion factors for the basic units into common American units are:
|
One gram equals |
0.0352739 ounces |
| One liter equals |
1.056710 quarts |
| One meter equals |
3.280833 feet |
Six place conversion factors are of little use to the traveler. You want to be able to relate
quantities in the European units to American units in a flash. It's like learning a foreign language,
but far easier because you don't need to learn any grammar.
Think in metric units, approximately. For example, consider the following conversions and
the round off approximations in the next column:
| Conversion Factor |
Round Off |
| 1 ounce |
28.349527 grams |
1 oz |
30 g |
| 1 kilogram |
2.204619 pounds |
1 kg |
2 lb |
| 100 grams |
3.52739 ounces |
100 g |
1/4 lb |
| 33 centiliters |
11.15884 fluid ounces |
33 cl |
11 fl oz |
| 1 liter |
1.06573 quart |
1 l |
1 qt or ¼ gal |
| 1 gallon |
3.785332 liters |
1 gal |
4 l |
| 1 inch |
2.538998 centimeters |
1 in |
2.5 cm |
| 1 foot |
30.48006 centimeters |
1 ft |
30 cm |
| 1 meter |
1.093611 yards |
1 m |
1 yd |
| 1 mile |
1.60931 kilometers |
1 mi |
1.6 km |
These approximations are close enough to get you through the day.
Familiar derivations of American units are also much different. For instance, automobile engine
sizes in the USA are normally rated by cubic inch displacement and Europeans use liters. One liter equals 61 cubic
inches. Our horsepower is equal to ¾ of their kilowatt (kw). Americans use kilowatts to
measure electricity, not automobile horsepower. For the tires, 30 psi equals approximately 2
atmospheres, 2 bars, and/or 2 kg/cm2. For you boaters, wind speed is measured in meters per
second and 10 m/s equals 19 knots. On land, 10 m/s equals 22 mph.
Oops, one last conversion factor – 35 liters per bushel.
The touted benefit of the metric system is that units are converted to higher or lower units
of measure by factors of ten only. On the other hand, the American system has twelve inches to
the foot, three feet to the yard, and many other odd divisions of units. One small absurdity of the
metric system is that almost nobody uses half of the named units, e.g. dekagrams and decigrams.
Hectograms are rarely used. I've only seen them in produce and fish markets in Italy.
Another problem with the metric system is the size of the basic unit of weight, the gram.
The only place where it is at all meaningful is in the post office for weighing mail, but even there
an ounce makes more sense than 28 grams. Besides, the maximum weight of an envelope for the minimum price is
only 20 grams, and if you think that USA postage rates are atrocious you will positively choke when you see
what it costs to send a letter across Paris.
Most products in Europe are sold by the kilogram, kg which is 1,000 grams, and equal to
about 2 pounds. But in Holland the word pond is used colloquially to mean 500 grams, slightly more
than an American pound. The Germans have their Pfund and the French their livre to
parallel the Dutch. There is obviously a practical need for a unit which is about equal to the American
pound but the metric system has nothing to offer. The Dutch also use the word ons for 100
grams when its true translation is ounce, and that is only 28 grams, not 100.
I don't know if McDonald's will have to rename their quarter pounder. In metric grams it would be a 113.5er.
International System of Units, SI
You may see the term SI in documents and scientific papers. This is the official name for the metric
system. The SI abbreviation is derived from the French name, Systeme International.
TEMPERATURE
Fahrenheit
America uses the Fahrenheit temperature scale. On this scale water freezes at 32o and boils
at 212o.
Centigrade
The Centigrade temperature scale is used in Europe. It is also called the Celsius scale
after its Swedish inventor. In Centigrade, water freezes at 0oC and it boils at 100oC. That is a 100
degree span and thus our old friend centi- again.
Fahrenheit and Celsius temperatures can be converted back and forth with a simple
algebraic expression. To convert Celsius to Fahrenheit multiply oC by 1.8 and add 32. To convert
Fahrenheit to Celsius subtract 32 from oF and then divide by 1.8.
I know that is too much math for a few of you (I teach algebra so I know whereof I speak),
and I seldom do it myself. Instead, keep some benchmarks in mind. Easy points to remember are:
| oC |
-20 |
-15 |
-10 |
-5 |
0 |
5 |
10 |
15 |
20 |
25 |
30 |
35 |
40 |
100 |
| oF |
-4 |
5 |
14 |
23 |
32 |
41 |
50 |
59 |
68 |
77 |
86 |
95 |
104 |
212 |
For every five Centigrade degrees add nine Fahrenheit degrees.
Key Temperatures
Normal body temperature of 98.6oF is equal to 37oC. The only temperature at which
Centigrade and Fahrenheit are the same is 40o below zero. You won't find me in town when that
happens.
TIME
When the metric system was introduced it also applied to time in France. After the Revolutionaries chopped
off the heads of the Royals they decided to get rid of the old 60 seconds per minute, 60 minutes
per hour, 24 hours per day, 7 days per week, and circa 52 weeks per year. They went to a decimal time system.
This featured 100 seconds per minute, 100 minutes per hour, 10 hours per day, and 10 days in a week. Napoleon
Bonaparte got that idiocy unhinged and France went back to the good old calendar. I guess that the
Revolutionaries would have had a better case if they had redefined the second as 13.6% less. Then the
annual reckening would be off by circa 5 days but even out in the next year. Not all change is good.
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