New York: Henry Holt and Company, 1916. First edition, first state. Hardcover. This is the first edition, first printing, first state of Frosts third published book. Mountain Interval is Frosts first book for which the U.S. edition takes precedence, both A Boys Will and North of Boston having been first published in Great Britain. Mountain Interval, which appeared in November 1916, offered readers some of his finest poems, such as Birches, Out, Out--, The Hill Wife, and An Old Mans Winter Night. (ANB) The volume opens with the poem The Road Not Taken. It was in 1916 that Frost was made Phi Beta Kappa poet at Harvard and elected to the National Institute of Arts and Letters. This copy is in good plus condition. First state is confirmed by repetition of the sixth line on p.88 and the word 'Come,' instead of 'Gone,' on p.93. (Crane A4, p.21) Condition is very good plus. The blue cloth binding remains square and tight with deep, unfaded color and…