Archive for ligature

Track and Trace & Ligatures

Posted in Covid-19, History with tags , , , , on November 2, 2020 by telescoper

I was interested to see (on Twitter) the above example of track-and-trace from 1665, at the height of the Great Plague of London. I’m not sure how effective this notice was…

Other than its historical context, looking at this piece of text reveals some interesting things about how it was printed.

Note the liberal use of the symbol “ſ’”, for example. This character is sometimes called the “long s”*. There’s a full Wikipedia article on this and I have posted about it before which means there’s no point in repeating here, but I will just mention that the long s was used widely in manuscripts after the distinction arose better upper case and lower-case letters (which was around about the end of the 8th Century) wherein the lower-case form, the “short s” (i.e. s),  was used exclusively at the end of words or before an elision, and the long s everywhere else. It survived into the era of printing, not just in English but also in other languages including German. In fact “ſ” forms the left-hand element of the ligature “Eszett”, written  “ß”, of which the other part is “z”.

Note the use of a ligature that looks like the Eszett at the end of the word “Sickness”. This is not actually an Eszett but is instead a ligature formed from the long s and the short s. I haven’t seen many examples of this in old printed books but I’m by no means an expert in 17th Century orthography but I’m given to  understand this was used in fonts based on the Antiqua class of typefaces, typically used for printing Latin text. I suppose the piece above was produced by a printer used to that form of material. That doesn’t narrow it down much, though, as many scholarly works were published in Latin at that time.

The number of esses (both long and short, as well as capital “S” in “Sickness” and “Swelling”) is quite considerable given its brevity. The last sentence contains quite a tongue-twister too: “said sign shall”!

There is another ligature “ct” in the word “infected” in the heading. This is quite common in old printed works, especially in Latin.  Here is an example from Newton’s Principia; see the word “rectam” in the statement of the Second Law of Motion:

The combination “ct” is quite common in Latin, as is “ss”, as are many other digraphs, including “et” (the ligature for which gives the symbol &; “et” means “and” in Latin).

Ligatures were introduced in handwriting, partly to embellish the script and partly to save time. Joining two letters together is a way of eliminating a duplicate stroke of the pen and avoiding having to lift it from the paper. When printing presses were introduced, ligatures were found to make typesetting with movable type easier because one block would replace frequent combinations of letters. It also allows the compositor to reduce the spacing between the characters, saving paper and also making the text easier to read.

*Incidentally, for the mathematically inclined, the long s is also the original form of the integral sign, introduced to mathematics by Leibniz to stand for “summa” (sum), which he wrote “ſumma”.



Ligatures, Diphthongs and Supernovae

Posted in History, Pedantry, The Universe and Stuff with tags , , , , , , , , on January 18, 2016 by telescoper

At the weekend I noticed a nice article by John Butterworth on his Grauniad blog about where Gold comes from. Regular readers of this blog (Sid and Doris Bonkers) know that I am not at all pedantic but my attention was drawn to the plural of supernova in the preamble:


I have to confess that I much prefer the latin plural “supernovae” to the modernised “supernovas”, although most dictionaries (including the One True Chambers) give these both as valid forms.  In the interest of full disclosure I will point out that I did five years of Latin at school, and very much enjoyed it…

When I tweeted about my dislike for supernovas and preference for supernovae some replied that English words should have English plurals so that supernovas was preferred (although I wonder if that logic extends to, e.g. datums and phenomenons). Others said that supernovae was fine among experts but for science communication purposes it was better to say “supernovas” as this more obviously means “more than one supernova”. That’s a reasonable argument, but I have to admit I find it a little condescending to assume that an audience can cope with the idea of a massive star exploding as a consequence of gravitational collapse but be utterly bewildered by a straightforward latin plural.

One of the reasons I prefer the Latin plural – along with some other forms that may appear archaic, e.g. Nebulae – is that Astronomy is unique among sciences for having such a long history. Many astronomical terms derive from very ancient sources and in my view we should celebrate this fact because it’s part of the subject’s fascination. That’s just my opinion, of course. You are welcome to disagree with that too.

Anyway, you might be interested to know a couple of things. One is that the first use of “super-nova” recorded in the Oxford English Dictionary was in 1932 in a paper by Swedish astronomer Knut Lundmark. This word is however formed from “nova” (which means “new” in Latin) and the first use of this term in an astronomical setting was in a book by Tycho Brahe, published in 1573:

Brahe_book(I’ll leave it as an exercise to the student to translate the full title.)

Nowadays a nova is taken to be a much lower budget feature than a supernova but the “nova” described in Tycho’s book was was actually a supernova, SN1572 which he, along with many others, had observed the previous year. Historical novae were very often supernovae, in fact, because they are much brighter than mere novae. The real difference between these two classes of object wasn’t understood until the 20th Century, however, which is why the term supernova was coined much later than nova.

Anyway, back to pedantry.

A subsequent tweet from Roberto Trotta asserted  that in fact supernovae and supernovas are both wrong; the correct plural should be supernovæ, in which the two letters of the digraph “ae” are replaced with a single glyph known as a ligature. Often, as in this case, a ligature stands for a diphthong, a sort of composite vowel sound made by running two vowels together.   It’s one of the peculiarities of English that there are only five vowels, but these can represent quite different sounds depending on the context (and on the regional accent). This  means that English has many hidden diphthongs. For example,  the “o” in “no” is a diphthong in English. In languages such as Italian, in which the vowels are very pure, “no” is pronounced quite differently from English. The best test of whether a vowel is pure or not is whether your mouth changes shape as you pronounce it: your mouth moves as you say an English “no”, closing the vowel that stays open in the Italian “no”…

So, not all diphthongs are represented by ligatures. It’s also the case that not all ligatures represent diphthongs. Indeed some are composed entirely of consonants. My current employer’s logo features a ligature formed from the letters U and S:


The use of the ligature æ arose in Mediaeval Latin (or should I say Mediæval?). In fact if you look at the frontispiece of the Brahe book shown above you will see a number of examples of it in its upper-case form Æ. I’m by no means an expert in such things but my guess is that the use of such ligatures in printed works was favoured simply to speed up the typesetting process – which was very primitive – by allowing the compositor to use a single piece of type to set two characters. However, it does appear in handwritten documents e.g. in Old English, long before printing was invented so easier typesetting doesn’t explain it all.

Use of the specific ligature in question caught on particularly well in Scandinavia where it eventually became promoted to a letter in its own right (“aesc”) and is listed as a separate vowel in the modern Danish and Norwegian alphabets.  Early word-processing and computer typesetting software generally couldn’t render ligatures because they were just too complicated, so their use fell out of favour in the Eighties, though there are significant exceptions to this rule. Latex, for example, always allowed ligatures to be created quite easily. Software – even Microsoft Word – is much more sophisticated than it used to be, so it’s now not so much of a problem to use ligatures in digital text. Maybe they will make a comeback!

Anyway, the use of æ was optional even in Mediaeval Latin so I don’t think it can be argued that supernovæ is really more correct than supernovae, though to go back to a point I made earlier, I do admit that a rambling discussion of ligatures and diphthongs would not add much to a public lecture on exploding stars.