Lepsius alphabet

The Standard Alphabet is a Latin-based alphabet developed by Karl Richard Lepsius. Lepsius initially used it to transcribe Egyptian hieroglyphs and extended it to write African languages, published in 1854 and 1855, and in a revised edition in 1863. The alphabet was comprehensive but was not used much as it contained a lot of diacritic marks and was difficult to read and typeset at that time.

Vowel length is indicated by a macron (ā) or a breve (ă) for long and short vowels, respectively. Open vowels are marked by a line under the letter (e̱), while a dot below the letter makes it a close vowel (ẹ). Rounded front vowels are written with an umlaut (ö [ø] and ü [y]), either on top or below, when the space above the letter is needed for vowel length marks (thus ṳ̄ or ṳ̆). Unrounded back vowels are indicated by a corner (˻) below e or i. (Central vowels may be written as one of these series, or as reduced vowels.)

As in the International Phonetic Alphabet, nasal vowels get a tilde (ã).

A small circle below a letter is used to mark both the schwa (e̥, also ḁ etc. for other reduced vowels) and syllabic consonants (r̥ or l̥, for instance).

Diphthongs do not receive any special marking, they are simply juxtaposed (ai [ai̯]). A short sign can be used to distinguish which element of the diphthong is the on- or off-glide (uĭ, ŭi) Vowels in hiatus can be indicated with a diaeresis when necessary (aï [a.i]).

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