ON THE CHARACTERISTICS OF THE VOWEL [Ъ] IN BULGARIAN GRAMMARS AND TEXTBOOKS FROM THE FIRST HALF OF THE 20TH CENTURY

This study traces the description and classification of the Modern Bulgarian vowel [ə] in six grammars and two textbooks from the first half of the 20th century. The works of linguists such as M. Ivanov, A. Teodorov-Balan, St. Mladenov, L. Andreychin, and others, who laid the foundations of contemporary Bulgarian linguistics, are exam-ined. Particular attention is paid to the differentiation between letter and sound, as well as to the challenges encountered in adapting various versions of the alphabet to the phonetic structure of Bulgarian at the turn of the 20th century. The study underscores the methodological approaches of Bulgarian linguists across generations and their efforts to provide a scientific systematisation of the vowel system, taking into account the influence of Neogrammarian ideas and subsequent European linguistic trends. The findings indicate that, despite some inconsistencies, this period marks the consolidation of the modern differentiation of the articulatory features of [ə].