Page:Sanskrit Grammar by Whitney p1.djvu/40

 sounds. In the Sanskrit, they wear the aspect of being products of the increment or strengthening of इ and उ  respectively; and they are called the corresponding -vowels to the latter (see below, 235 ff.). The other two, ऐ and औ, are held to be of peculiar Sanskrit growth; they are also in general results of another and higher increment of इ  and उ , to which they are called the corresponding -vowels (below, 235 ff.). But all are likewise sometimes generated by euphonic combination (127); and ओ, especially, is common as a result of the alteration of a final अस् (175).

The ए and ओ  are, both in India and Europe, usually pronounced as they are transliterated — that is, as a long e- (English “long a”, or e in they) and o-sounds, without diphthongal character.

Such they apparently already were to the authors of the Prātiçākhyas, which, while ranking them as diphthongs, give rules respecting their pronunciation in a manner implying them to be virtually unitary sounds. But their euphonic treatment (131–4) clearly shows them to have been still at the period when the euphonic laws established themselves, as they of course were at their origin, real diphthongs, ai (a + i) and au (a + u). From them, on the same evidence, the heavier or diphthongs were distinguished by the length of their a-element, as āi (ā + i) and āu (ā + u).

The recognizable distinctness of the two elements in the -diphthongs is noticed by the Prātiçākhyas (see APr. i. 40, note); but the relation of those elements is either defined as equal, or the a is made of less quantity than the i and u.

The lighter or -diphthongs are much more frequent (6 or 7 times) than the heavier or -diphthongs, and the and  than the  and  (a half more). Both pairs are somewhat more than half as common as the simple - and -vowels.

The general name given by the Hindu grammarians to the vowels is tone; the simple vowels are called  homogeneous syllable, and the diphthongs are called  combination-syllable. The position of the organs in their utterance is defined to be one of openness, or of non-closure.

As to quantity and accent, see below 76 ff., 80 ff.