Chambers's Twentieth Century Dictionary…
“ The, the, or (when emphatic) thē, demons. pron. usually called the definite article, used to denote a particular person or thing: also to denote a species. [A.S. the, rarely used as nom. masc. of def. art., but common as an indeclinable relative. Cf. That.] The, the, adv. used before comparatives, as, 'the more the better.' [A.S. thý, by that, by that much, the instrumental case of the def. art.] ”
