Most people know that when something is “unilateral” it applies to one side only. If an agreement is unilateral, it’s not really an agreement because only one side has agreed. There can also be unilateral disarmament, unilateral decisions, and so on.
The word is derived from the Latin word “unilateralis,” which in turn was assembled from “unus” (one) and “latus” (side). It’s pretty clear, and it’s a well-known, commonly-used word. So why am I talking about it? It’s simply here to introduce its cousin “uniliteral,” which is not common at all, although what it describes is extremely common.
“Uniliteral” means “composed of a single letter. The words “a” and “I” are “uniliteral.” The derivation of uniliteral is about the same as for “unilateral,” except that instead of a side it refers to a letter. It’s not really a very useful word. There aren’t very many times you need to talk about a “one-letter word,” although it would technically apply to anything made up of a single letter. There aren’t all that many of those, either, whatever they might be (other than words, of course). I suppose a sadistic algebra teacher might construct some sort of test question about a multivariate formula and insist that students’ answers be “uniliteral.” But “uniliteral” is definitely more useful than that, which is another entry from my also-hardly-useful antique quiz book about railroads:
At the beginning of the year 1954, there were 37,251 train locomotives operating in the US. Of these, 24,209 were diesel-electric, 12,274 were steam, 713 were electric, 15 were gas-electric. Gas-electric means they had gasoline-powered engines — these would have been gas turbine engines, not like the engines in autos — that powered generators, and the generators supplied electricity to power the electric motors. But that leaves 40 locomotives. Those 40 are a bit of a mystery; they’re simply listed as “other.” But what other way is there to power a train?
There have been a very few experimental fuel-cel-powered locomotives, but not as many as 40 in the entire world. By the way, if you’re thinking that 1954 was too early for fuel cells, nope. Fuel cells were invented in 1838, and were commercially available in the 1930s.
The 1950s was also the time when people seemed to think that atomic power was going to be used in all sorts of ways that seem outlandish nowadays. “Atomic-powered trains” were definitely discussed, as were atomic-powered ships and even planes and cars. But the only type ever built (as far as I can find) were ships, and they turned out to be much too expensive for any organization other than governments to even consider.
There have been some locomotives powered by automotive-style gasoline engines, so some of the 40 might be that type. There is also a variety of locomotive called a “drone” that contains electric motors but no generators. They’re used in conjunction with a diesel-electric locomotives to provide additional traction and braking; the diesel-electric provides the power and the drone provides additional wheels and motors. So that might make up some (or even all) of the 40 “other” locomotives too. In any case, there was no time to worry about this, at least not back in 1954, because they were so busy with the mail. In the 1950s, trains carried 80% of the mail in the US. I don’t know what the percentage is today, but it’s probably a lot closer to a uniliteral number.