Squirrel tracks.

How did I know they were squirrel tracks?

The night and earlier morning gently dusted us with a dry inch of snow--enough to show who's been by. I walked through the back yard and all the way to the back of the tiny wood, but saw signs of only two visitors: a squirrel and probably a rabbit. No coy wolf--though it's true the snow was only hours old, and an urban eastern coyote would typically roam a three-square-mile area. I took the regular photos of my Wild Place.

A BRIEF AND THOUGHTFUL RANT

(

**Might As Well Put This Here as Anywhere Else!)***or*
Many Americans despise the metric
system of measurements--the Systeme Internacional. I do not, but neither do I follow it
slavishly. You may have noticed me mix
the measurements even within the same post, as I did in "Domestic
Science."

I grew up with the English--or "customary"--units
of measure: inches, feet and miles,
pints, quarts and gallons, ounces, pounds and tons, and so forth. I well remember being taught that America was
going metric, so we'd better learn it; this was in third grade in about
1967. You'll have noticed by now we've
been easing into it pretty slowly! (As far as I am aware, the only time most of
us use metric units is to buy soda!) I am pretty comfortable with millimeters,
meters and kilometers, though, as well as grams, kilograms and tonnes, and
milliliters and liters. They are
universally used in the sciences which are my background.

Metric units have two great
advantages over customary units. First,
they are more fundamentally derived: the meter comes (originally) from French
measurements of the distance from the north pole to the equator through
Paris. A cube 1 centimeter on a side
contained a volume of 1 milliliter, and this volume of water has a mass of one
gram--all neat and tidy! The second and
a very practical advantage came when you had to do any kind of math: all the
units related directly to each other, and all by powers of ten. For example, a distance of 1000 meters was
one kilometer, while a meter in turn contained 1000 millimeters. A liter bottle of water has a mass of one kilogram. Quick: since a mile is 5280 feet and a foot
is 12 inches, figure out how many inches are in a mile! Doing
math in the metric system, by contrast, reduces to merely keeping track of the
decimal point!

On the other hand, having
physically-derived units doesn't make a system practical, and having units that
relate by powers of ten limits, somewhat, their flexibility in size. for example, I am 6'2" tall. In the metric system, my height would usually
be represented as 188cm --in my opinion, a rather unwieldy number of
digits. Feet and inches are better sized
for many everyday purposes than centimeters and meters. Furthermore, breaking down units fractionally
has its own elegant simplicity: if you want a smaller unit, just halve the one
you've got by doubling the denominator: 1/2 inch, then 1/4 inch, then 1/8 inch,
and so on, limited only by the steadiness of your hands, the acuity of your
eyesight, and your technology. The
problem is it does force one to get down
and diry with fractions, which still don't come easily to me. Here's an example I wrestle with frequently.
Put these drill bits in ascending order of size: 5/32, 1/8, 11/64.

Finally, although the Celsius
scale of temperature measurement is elegant in dividing the temperature
difference between the melting point and boiling point of water into 100 equal
parts, those parts--the Celsius degrees--are almost twice as big as Fahrenheit
degrees, and they force you to use negative numbers in winter.

Therefore, I will continue to mix
my systems in these posts: metric if much math is involved, English if it's much
more convenient in size, and Fahrenheit pretty much always!

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