Сколько букв в древнеславянском языке?
The number of letters in the original Glagolitic alphabet is not known, but it may have been close to its presumed Greek model. The 41 letters known today include letters for non-Greek sounds, which may have been added by Saint Cyril, as well as ligatures added in the 12th century under the influence of Cyrillic, as Glagolitic lost its dominance. In later centuries, the number of letters dropped dramatically, to fewer than 30 in modern Croatian and Czech recensions of the Church Slavic language. Twenty-four of the 41 original Glagolitic letters (see table below) probably derive from graphemes of the medieval cursive Greek small alphabet but have been given an ornamental design.
41