[…] there is a third product of the same three positions of mute-closure. By dropping, namely, the veil of the palate, which in ordinary utterance closes the passage from the pharynx into the nose, the intonated current of ‘b’, ‘d’, ‘g’ is allowed entrance to the nose and exit there: and the result is the class of nasals (or “resonants”), ‘m’, ‘n’, and ‘ng’ (as in ‘singing’). Here, though there is closure of the mouth-organs, the tone is so sonorous and continuable that the breach of contact, or explosion, is reduced to a very subordinate value, and the class belongs high up in the alphabet, toward the vowels.
- Whitney (1875), a pag.63