West looks back to the year 1900; 1900, by Rebecca West. New York: The Viking Press. 190 pp. $19.95.

This extraordinarily handsome picture-and-text book recalls a vanished age with equal parts admiring nostalgia and acerbic commentary. The pictures - mostly period photographs, many extremely rare - display such wonders as the construction of the New York subway and such notable figures as Chekhov and Tolstoy and Queen Victoria.

The text, in a different way quite as wonderful, consists of notes accompanying the illustrations, plus a central, long essay by the ferociously august and witty Dame Rebecca West.

''1900'' is no mere coffeetable book; it's an incisive and fascinating historical argument.