Long s

The long, medial, or descending s (ſ) is a form of the minuscule (lower-case) letter s, which was formerly used where s occurred in the middle or at the beginning of a word (e.g. "ſinfulneſs" for "sinfulness" and "ſucceſsful" for "successful"). The modern letterform was called the terminal, round, or short s.

The long s was derived from the old Roman cursive medial s. When the distinction between majuscule (uppercase) and minuscule (lowercase) letter forms became established, toward the end of the eighth century, it developed a more vertical form. During this period, it was occasionally used at the end of a word, a practice that quickly died but that was occasionally revived in Italian printing between about 1465 and 1480. Thus, the general rule that the long s "never occurred at the end of a word" is not strictly correct, although the exceptions are rare and archaic. The double s in the middle of a word was also written with a long s and a short s, as in Miſsiſsippi. In German typography, the rules are more complicated: short s also appears at the end of each component within a compound word, and there are more detailed rules and practices for special cases.

The long s is often confused with the minuscule f, sometimes even having an f-like nub at its middle, but on the left side only, in various Roman typefaces and in blackletter. There was no nub in its italic typeform, which gave the stroke a descender that curled to the left and which is not possible without kerning in the other typeforms mentioned. For this reason, the short s was also normally used in combination with f: for example, in "ſatisfaction".

The nub acquired its form in the blackletter style of writing. What looks like one stroke was actually a wedge pointing downward. The wedge's widest part was at that height (x-height), and capped by a second stroke that formed an ascender that curled to the right. Those styles of writing and their derivatives in type design had a cross-bar at the height of the nub for letters f and t, as well as for k. In Roman type, except for the cross bar on medial s, all other cross bars disappeared.

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