Siamese is spoken from Burmah and British Burmah on the west to Anam and Cambodia on the east, and from the Malay state of Keddah on the south to the confines of China on the north. The dialectical variations are numerous, and the language-is spoken well only in Bangkok and by persons educated there. (See Indo-CHINESE and Languages.) The Siamese alphabet, supposed to be derived from the ancient Cambodian letters still used in Siamese sacred books, and ultimately from the original Pali alphabet, consists of 44 consonants and 20 vowels, including diphthongs and semi-vowels. The gradation of the vowel sounds is very delicate, and some of the consonants are but slightly changed forms of the same letter, indicating the tone in which they are to be uttered in certain syllables. The English g j, v, x, and z are wanting. The th sound, though frequent in Burmese, is entirely unknown in Siamese, the th used in transcriptions of the latter representing an aspirated t, or a combined utterance of the two sounds t and h. According to the tone in which it is uttered, a word has several distinct meanings, by means of which the otherwise very meagre vocabulary is considerably increased.

Thus hkai, hkai, hkai, pronounced in the same tone, would mean who? who? who?; but enunciating each with a different tone, it may be made to mean " Who sells eggs ? " This same word hkai may further be made to signify a fever, to open, rough, fortress, or camp, by other intonations. Besides the parts of speech distinguished in English grammar, there is in Siamese a peculiar class of numeral or classifying nouns. Such a word is lam, which is used in conjunction with objects having the quality of length, as ships and palm trees; others of this class are an, toa, luk, ton, and met, all of which must be used when speaking of one or another class of objects. Three genders, masculine, feminine, and common, are distinguished by the grammarians, but in common speech and in poetry gender is commonly disregarded, except in distinctions of sex, which is indicated by the addition of special words. The plural is expressed by adding some word like hlai, many, or mak, much. There are no inflections, and case is indicated by the use of a preposition, or by the position of the word in the sentence. There is a great variety of pronouns, or pronominal expressions, and the proper use of one or another depends on the relative rank of those writing or speaking.

Moods and tenses are indicated by prefixes and suffixes, or by auxiliary verbs; thus hka bok, I say; hka dai bok, I have said; hka hka bok, I shall say, etc. The Siamese are very fond of using words in pairs, for euphony, distinctness, or figurativeness. - Siamese.literature is not of a very high order. The works on history and medicine contain little else but fables and quackery. The law books are very elaborate, but wanting in legal acumen and precision. The religious and philosophical productions are based upon the Pali scriptures and Chinese learning, and exhibit nothing of an original growth. The books of Siamese proverbs, however, have been praised as containing much social wisdom sharply put. The best productions of Siamese literature are works of fiction, poems, and dramas, though a large portion of them are borrowed from or imitations and adaptations of Hindoo works. - See Pallegoix, Grammatica, Linguae Thai (Bangkok, 1850), and Dictionarium Lingua) Thai (Paris, 1854); Bastian, Reisen in Siam (Berlin, 1867), which contains learned disquisitions on the language and literature of the country; Alabaster, "Wheel of the Law" (London, 1871); and the " Siam Repository," a journal published at Bangkok in English.