Reversed half H
The reversed half H was a letter used in Latin inscriptions from Roman Gaul. In French epigraphy works, it is called H dimidiée, "halved H".
History
It is derived from the right part of. It represents the aspirate h or rough breathing. It is found at the beginning of words, and following c, p, and t, in words which have an original Greek χ, φ or θ. It may or may not be related to the characters ⊢ and ⊣ used by Aristophanes of Byzantium to represent the rough breathing and smooth breathing of Greek around 200 BC.The half H is found in Latin inscriptions of Gaul, particularly the areas of Lugdunum and Nemausus in modern France. Of the variant forms of H found in inscriptions, the reversed half H is the only one commonly distinguished from the ordinary H in diplomatic transcriptions.
A few authors have considered the reversed half H to be a ligature of H with the preceding letter, but Corpus Inscriptionum Latinarum and catalogues of local inscriptions treat the reversed half H as a distinct letter. There are cases of clear ph, nth, HI, HE, HR ligatures but, in others, there is visible space between Ꟶ and the previous and following letter.