Alpha is the name of the sound A. Seven of the letters are vowels, a, e, e, i, o. u, o, and six are mutes, b, g, d, k, p, t. There is a difference between voice and speech ; because, while voice may include mere noise, speech is always articulate. Speech again differs from a sentence or statement, because the latter always signifies something, whereas a spoken word, as for example fikirvpi, may be unintelligible which a sentence never is. And to frame a sentence is more than mere utterance, for while vocal sounds are uttered, things are meant, that is, are matters of discourse. There are, as stated by Diogenes a in his treatise on Language and by Chrysippus, five parts of speech : proper name, common noun, verb, conjunction, article. To these Antipater in his woi'k On Words and their Meatiing adds another part, the " mean." b A common noun or appellative is defined by Diogenes as part of a sentence signifying a common quality, e.g. man, horse ; whereas a name is a part of speech expressing a quality peculiar to an individual, e.g. Diogenes, Socrates. A verb is, according to Diogenes, a part of speech signifying an isolated predicate, or, as others define it, an undeclined part of a sentence, signifying something that can be attached to one or more subjects, e.g. " I write," " I speak." A conjunction is an indeclinable part of speech, binding the various parts of a statement together ; and an article is a declinable part of speech, distinguishing the genders and numbers of nouns, e.g. 6, ?/, to, 01, at, rd. d There are five excellences of speech — pure Greek, lucidity, conciseness, appropriateness, distinction. By good Greek is meant language faultless in point