Guttural, Palatal, Lingual, Dental, Labial

Guttural, Palatal, Lingual, Dental, Labial
He established twenty-two letters fundamentally by the voice, formed by the breath of air and fixed them on five places in the human mouth, namely:
One at the throat {guttural sounds}, Aleph, Hay, Chet, Ayin.                  
Two at the palate {palatal sounds}, Gimel, Yod, Kaf, Qof.
Three, at the tongue {lingual sounds}, Dalet, Tet, Lamed, Nun, Taw.
Four, at the teeth {dental sounds}, Zain, Shin, Samekh, Resh, Tzaddi.
Five, at the lips {labial sounds}, Bet, Vau, Mem, Peh.”
 (Sefer Yitzirah chapter two, section three.)