The Metric Caboose

By The Metric Maven

Mini-Bulldog Edition

As a boy, I lived less than a block from a set of railroad tracks. The report of train whistles, and the low pitched sound of each train as it passed by during the night assured me commerce was underway, and all was fine. During the day, myself and others would often watch as a train passed to see what the oldest car was. The oldest was 1909 as I recall, and those cars looked very fragile. Of course the caboose was a punctuating symbol that defined the end of the train. I don’t ever recall a caboose at the front of the train. A caboose at the front of a train, before the engines, would be seen as something out of order, that is not being used as designed. Could one hook a caboose to the front of a train and have it operate? Sure—does it make sense–perhaps—but not as expected usage.

When I first became interested in electronics, resistors were the first component I encountered. Their resistance is measured in ohms. One might have 50 ohm resistor, or 68 ohm resistor, but when the value progresses into the thousands, the metric prefix Kilo is used. A 10 000 ohm resistor is a 10 Kiloohm resistor which is generally written as 10 KΩ, when the resistance becomes large enough we use Megaohms or MΩ. As people like to speak in shorthand, and everyone knows, that on an electrical schematic, resistors are in ohms, electrical engineers generally say “that’s a 4 K resistor,” implying that the value is 4 KΩ. When people say they are going to participate in a 5K run, it’s understood that it is a 5 Km distance.

The metric prefix Kilo- is supposed to modify the unit value that follows it, but in common usage, people often appear to use it as shorthand for a set of zeros. When the prefix symbol is moved next to a numeral, 5K becomes 5000; the prefix modifier becomes a suffix modifier. When it is thought of in this way, it can be used as a sort of stealth prefix for Ye Olde English, or whatever comes along.

For instance here is an example from the web where the metric modifier is separated from Olde English as if this is a good idea:

So it reads “Spruce beetles pick up where their pine cousins left off, eating through 136 000 acres in past year” rather than “Spruce beetles pick up where their pine cousins left off, eating through 136 Kiloacres in past year.” The prefix modifier becomes a suffix modifier and metric is “compatible” with anything. Just by removing a space we modify the leading number rather than the trailing unit. By invoking this idea, we create 5K dollars, or 75K crickets, or 210K albatrosses. This space removal causes a literary switcharoo that turns a prefix into a suffix. This appears to be a practice that has happened somewhat recently and has become an accepted part of the language. If there is no space between it and a leading number, the single metric “prefix”  becomes a suffix number, and if there is a space then a metric unit must follow the prefix.

Is this usage a good idea? I’m not sure. Perhaps this is a usage that could make sense. Without a space 326K, or 326M, or 326G could be thought of as numbers. The value 326G certainly is more compact than 326 000 000 000. This distinction would have to be identified, formalized, and taught in schools, so that students would know how to use it properly. If one writes 25K they mean a number, if they write 25 K then one should expect a unit symbol to follow such as 25 Km, and 25 K would not be considered a finished statement. I can see how this usage could be useful, but currently it strikes me as the engine switched for the caboose.

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Related essay:

The Elements of Bile

The Metric Maven has published a book titled The Dimensions of The Cosmos. It examines the basic quantities of the world from yocto to Yotta with a mixture of scientific anecdotes and may be purchased here.


How Many Lines are in a Loan?

By The Metric Maven

Bulldog Edition

The first area I recall comprehending was “a block,” whose boundaries I was instructed not to cross. Growing up in a small town, I quickly learned who lived in each of the houses on my block. I knew the name of each family and the first names of each occupant. I was told that 12 city blocks equal one mile. I immediately assumed, without thought, that this length would be that of a single edge of each block in a line. After all, wooden building blocks have equal sides, and I had considerable experience with them. I did not confuse area and linear extent, it seemed obvious. What seems natural to most people is to name areas as an independent dimension. It is so natural that a vast number of defined areas were accepted around the world prior to the metric system. When the metric system was originally developed, this penchant for an area that is arbitrarily defined was adopted. The unit of area in the metric system was given as the are. An are is equal to 100 square meters, because?—I have no idea.

People don’t think about the fact that when expressing total area, we divide the area of interest up using an arbitrary shape of enclosed area. We could use circular meters, or equilateral triangle meters, but we have chosen to use squares with one meter sides. *  The are has sides with lengths that are the square root of 100 meters, or 10 meters. Why choose ten?—no idea—other than area had always been arbitrarily chosen in the past and ten can become a thoughtless fetish for the are. My favorite reference has this set of equivalent named pre-metric areas in terms of an are:

There are about 130 named areas listed in terms of an are, including a line and a loan. Despite what George Orwell might think, this large number of names for non-equivalent named areas only leads to a lack of comprehension, not a clearer description. It does not make them “more human” unless it is meant they produce more opportunity for human fraud.

Metric prefixes were then applied to the are, to create other areas. The most common one used is hectare, which is 10 000 square meters. Why? I can only guess that it’s like
a myriameter of area? Whenever one of the prefix cluster around unity is implemented in the metric system, it produces a kludge. We could have decaares or daa (yes deca or deka has  a two letter prefix da). How about deciares or da, or centiares?—-longtime readers know what I think of this already. Thankfully, the modern official SI is square meters, but once a bad usage has been adopted, it takes an act of Congress (which never happens with the metric system) to change anything. Hectares are still with us, and in the US they are a sure sign of Americans Using The Metric System. Recently on Vice News (2017-01-24) I saw a graph, presented on-screen that showed the increase in poppy cultivation in Mexico had gone from 10 K to 30 Kha indicating the base unit is hectares. It’s easy to understand why this chart has such poor metric usage, it was generated by the White House:

So the White House took hectares and then produced Kilohectares (Kha) by concatenating metric prefixes. So they did not use square meters or square Kilometers, they instead  used ares with the metric prefix hecto, then concatenated Kilo to create Kilohecto. It reminds me of when I lived in a Spanish speaking country and if a person there did not speak English, the answer was to say a phrase louder, modifying an English word so that it sounded like Spanish to that person. I recall a person loudly asking a waiter for “El knife-o.”

So how large is 10 Kha to 30 Kha in metric?  A hectare is 10 000 square meters, with a Kilo at the front becomes 10 000 000 square meters or about 10 square Kilometers. The production has gone from around 10 square Kilometers to almost 30 square Kilometers.

The chart has two axes on it, the other is the amount of potential production in MT, which I can assume is not Montana, but is instead Metric Tonnes. At least they didn’t need to use another prefix with MT. Would Mg for Megagrams really have caused that much confusion, when MT is not even defined on the graph.

So in 2011 about 11 square Kilometers could produce about 30 Megagrams of poppies or about 2.7 Mg/Km2, by 2015 it is about 70 Mg over an area of 28 Km2 or about 2.5 Mg/Km2. The yield per square Kilometer is about the same.

This chart was only on screen for a few seconds, has two axes, uses ill-defined units, and is therefore typical of what I often see in the media. Telling the story is generally more important than conveying information. The measurement free-for-all that is the US, conspires to reduce our numeracy the same way that 130 named areas dilutes the meaning of 100 square meters.

* A more in-depth discussion of this choice for area shape is found in The Dimensions of The Cosmos (pp 29-31).

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The Metric Maven has published a book titled The Dimensions of The Cosmos. It examines the basic quantities of the world from yocto to Yotta with a mixture of scientific anecdotes and may be purchased here.