did double duty: ח and ע . In both of these cases, however, the two sounds represented by the same letter eventually merged, leaving no evidence (other than early transcriptions) of the former distinctions. Although early Aramaic (pre-7th century BCE) had only 22 consonants in its alphabet, it apparently distinguished all of the original 29 Proto-Semitic phonemes, including , , , , , and although by Middle Aramaic times, these had all merged with other sounds. This conclusion is mainly based on the shifting representation of words etymologically containing these sounds; in early Aramaic writing, the first five are merged with , , , , , respectively, but later with , , , , . (Also note that due to begadkefat spirantization, which occurred after this merger, OAm. t > ṯ and d > ḏ in some positions, so that PS *t,ṯ and *d, ḏ may be realized as either of t, ṯ and d, ḏ respectively.) The sounds and were always represented using the pharyngeal letters , but they are distinguished from the pharyngeals in the Demotic-script papyrus Amherst 63, written about 200 BCE. This suggests that these sounds, too, were distinguished in Old Aramaic language, but written using the same letters as they later merged with. The earlier pharyngeals can be distinguished in Akkadian from the zero reflexes of *ḥ, *ʕ by e-coloring adjacent *a, e.g. pS *ˈbaʕal-um 'owner, lord' > Akk. bēlu(m). Hebrew and Aramaic underwent begadkefat spirantization at a certain point, whereby the stop sounds were softened to the corresponding fricatives (written ḇ ḡ ḏ ḵ p̄ ṯ) when occurring after a vowel and not geminated. This change probably happened after the original Old Aramaic phonemes disappeared in the 7th century BCE, and most likely occurred after the loss of Hebrew c. 200 BCE. It is known to have occurred in Hebrew by the 2nd century CE. After a certain point this alternation became contrastive in word-medial and final position (though bearing low functional load), but in word-initial position they remained allophonic. In Modern Hebrew, the distinction has a higher functional load due to the loss of gemination, although only the three fricatives are still preserved (the fricative is pronounced in modern Hebrew). In the Northwest Semitic languages, became at the beginning of a word, e.g. Hebrew yeled "boy" < *wald (cf. Arabic walad). There is evidence of a rule of assimilation of /j/ to the