to make new a form that was fast running out of steam. 20th century As part of his attempted renewal of poetic prosody, Gerard Manley Hopkins had applied his experimental sprung rhythm to the composition of the sonnet, amplifying the number of unstressed syllables within a five- (or occasionally six-) stressed line – as in the rhetorical "The Windhover", for example . He also introduced variations in the proportions of the sonnet, from the 10 lines of the curtal sonnet "Pied Beauty" to the amplified 24-line caudate sonnet "That Nature is a Heraclitean Fire". Though they were written in the later Victorian era, the poems remained virtually unknown until they were published in 1918. The undergraduate W. H. Auden is sometimes credited with dispensing with rhyme altogether in "The Secret Agent", but went on to write many conventional sonnets, including two long sequences during the time of international crisis: "In Time of War" (1939) and "The Quest" (1940). Sequences by some others have been more experimental and looser in form, of which a radical example was "Altarwise by owl-light" (1935), ten irregular and barely rhyming quatorzains by Dylan Thomas in his most opaque manner. In 1978 two later innovatory sequences were published at a period when it was considered that "the sonnet seems to want to lie fallow, exhausted", in the words of one commentator. Peter Dale's book-length One Another contains a dialogue of some sixty sonnets in which the variety of rhyming methods are as diverse as the emotions expressed between the speakers there. At the same time, Geoffrey Hill's "An Apology for the Revival of Christian Architecture in England" appeared in Tenebrae (1978), where the challenging thirteen poems of the sequence employ half-rhyme and generally ignore the volta. Seamus Heaney also wrote two sequences during this period: the personal "Glanmore Sonnets" in Field Work (1975); and the more freely constructed elegiac sonnets of "Clearances" in The Haw Lantern (1987). In North America USA The earliest American sonnet is David Humphreys's 1776 sonnet "Addressed to my Friends at Yale College, on my Leaving them to join the Army". The sonnet form was used widely thereafter, including by William Lloyd Garrison and William Cullen Bryant. Later, Henry Wadsworth Longfellow and others followed suit. His were characterised by a "purple richness of diction" and by their use of material images to illustrate niceties of thought and emotion. He also translated several