Question: Who was Vaughan Williams' friend who helped collect folk songs in southern England and was a founding father of the folk-song revival in England in the early 20th century?

Context paragraphs:
Mary Sands: Mary Bullman Sands (April 8, 1872 – April 2, 1949), from Allanstand in Madison County, North Carolina, was a singer of old traditional ballads during the early part of the 20th century.  She was known locally as "Singing Mary" due to her singing talent and extensive knowledge of the words and melodies of many old-time traditional songs that had been passed down through previous generations.  In 1916, English folklorist Cecil Sharp visited Madison County to collect and record traditional folk songs being sung in America that would have originated generations earlier in the British Isles.  Sands sang 25 songs for him, 23 of which he included in his book, "English Folk Songs from the Southern Appalachians".

Ralph Vaughan Williams: Ralph Vaughan Williams {'1': ", '2': ", '3': ", '4': "} ( 12 October 1872– 26 August 1958) was an English composer.  His works include operas, ballets, chamber music, secular and religious vocal pieces and orchestral compositions including nine symphonies, written over nearly fifty years.  Strongly influenced by Tudor music and English folk-song, his output marked a decisive break in British music from its German-dominated style of the 19th century.

Lucy Broadwood: Lucy Etheldred Broadwood (9 August 1858 – 22 August 1929) was an English folksong collector and researcher during the late 19th and early 20th centuries.  As one of the founder members of the Folk-Song Society and Editor of the Folk Song Journal, she was one of the main influences of the English folk revival of that period.  She was an accomplished singer, composer, piano accompanist, and amateur poet.  She was much sought after as a song and choral singing adjudicator at music festivals throughout England, and was also one of the founders of the Leith Hill Music Festival in Surrey.

History of ecology: Ecology is a new science and considered as an important branch of biological science, having only become prominent during the second half of the 20th century.  Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics.  Its history stems all the way back to the 4th century.  One of the first ecologists whose writings survive may have been Aristotle or perhaps his student, Theophrastus, both of whom had interest in many species of animals and plants.  Theophrastus described interrelationships between animals and their environment as early as the 4th century BC.  Ecology developed substantially in the 18th and 19th century.  It began with Carl Linnaeus and his work with the economy of nature.  Soon after came Alexander von Humboldt and his work with botanical geography.  Alfred Russel Wallace and Karl Möbius then contributed with the notion of biocoenosis.  Eugenius Warming’s work with ecological plant geography led to the founding of ecology as a discipline.  Charles Darwin’s work also contributed to the science of ecology, and Darwin is often attributed with progressing the discipline more than anyone else in its young history.  Ecological thought expanded even more in the early 20th century.  Major contributions included: Eduard Suess’ and Vladimir Vernadsky’s work with the biosphere, Arthur Tansley’s ecosystem, Charles Elton's "Animal Ecology", and Henry Cowles ecological succession.  Ecology influenced the social sciences and humanities.  Human ecology began in the early 20th century and it recognized humans as an ecological factor.  Later James Lovelock advanced views on earth as a macro-organism with the Gaia hypothesis.  Conservation stemmed from the science of ecology.  Important figures and movements include Shelford and the ESA, National Environmental Policy act, George Perkins Marsh, Theodore Roosevelt, Stephen A. Forbes, and post-Dust Bowl conservation.  Later in the 20th century world governments collaborated on man’s effects on the biosphere and Earth’s environment.

Cecil Sharp: Cecil James Sharp (22 November 1859 – 23 June 1924) was the founding father of the folk-song revival in England in the early 20th century.

Blacksmith (song): "Blacksmith" (Roud 816) is a traditional English folk song, also known as "A Blacksmith Courted Me".  The song was noted down by Ralph Vaughan Williams in 1909 from a Mrs Ellen Powell of Westhope near Weobley, Herefordshire.  On that occasion it was sung to the tune "Monk's Gate", better known as the tune of "To be a pilgrim", the hymn by John Bunyan.  The same tune is sometimes used for the song "Our Captain Cried".  There is a setting by George Butterworth (a friend of Vaughan Williams and Cecil Sharp) in his 1912 collection "Folk Songs from Sussex" (recorded by Roderick Williams and Iain Burnside in the Naxos English Song Series 8.572426).

Somerset Carol: Come all you worthy gentlemen, sometimes referred to as the Somerset Carol, is an English folk carol of unknown authorship.  It was collected from a Mr. Rapsey, of Bridgwater during the English Folk-song revival at the turn of the 20th century by Cecil Sharp.  It was first published in 1905 in Sharp and Marson's "Folk songs from Somerset".

Croatian tamburica: Croatian tamburitza (tam•bu•rit•za) is a folk song played with a tambura (cousins with Russian balalaika and the Italian mandolin) and is accompanied with a dance.  The origin is most commonly thought to be introduced from the Turks by way of Bosnia between the 14th and 16th century.  Although, others believe that the tambura was introduced by the Persians.  It was not until the 19th century that tamburitza gained popularity during several nationalist movements against the Austro-Hungarian Empire.  Many societies such as Croatian, Slovak and Czech, used national folk songs and dance as an "expression of their national identity".  During this time, the first Croatian tamburitza ensemble was created by Pajo Kolarić in 1847.  Also, during early 20th century ethnomusicologist Professor Vinko Žganec, began to write down Croatian folk songs which in the past were not written, but passed down from generation to generation.

A Sea Symphony: A Sea Symphony is a piece for orchestra and chorus by Ralph Vaughan Williams, written between 1903 and 1909.  Vaughan Williams' first and longest symphony, it was first performed at the Leeds Festival in 1910, with the composer conducting.  The symphony's maturity belies the composer's relative youth when it was written (he was 30 when he first began sketching it).  One of the first symphonies in which a choir is used throughout the work and is an integral part of the musical texture, "A Sea Symphony" helped set the stage for a new era of symphonic and choral music in Britain during the first half of the 20th century.  The work is sometimes referred to as the Symphony No. 1.

Fantasia on Christmas Carols: Fantasia on Christmas Carols is a 1912 work for baritone, chorus, and orchestra by the English composer Ralph Vaughan Williams.  First performed at the 1912 Three Choirs Festival at Hereford Cathedral, the work is a single movement of roughly twelve minutes which consists of the English folk carols "The truth sent from above", "Come all you worthy gentlemen" and "On Christmas night all Christians sing" (i.e. the Sussex Carol), all folk songs collected in southern England by Vaughan Williams and his friend Cecil Sharp a few years earlier.  These are interposed with brief orchestral quotations from other carols, such as "The First Nowell".  The early work remains popular with choral societies, and is sometimes paired with his longer Christmas work "Hodie" of 1954.  There is also a version of the "Fantasia" which replaces the orchestra with strings and organ.  A purely orchestral version, in which the solo vocal and choral parts were 'cued in' on the orchestral instruments, was performed in Studio 8H, New York, on 19 December 1943 by the NBC Symphony conducted by Leopold Stokowski.  The broadcast of this unpublished version, which was presumably arranged by the conductor, has been released on a 'Guild Historical' CD and is also uploaded on YouTube.

Supporting paragraphs: Fantasia on Christmas Carols Cecil Sharp
Answer: Cecil Sharp