A little information which may be of use....

Henderson undertook a 16 week tour of Australia from December 1907 for the Harry Rickard vaudeville circuit. Far too many press notices to quote here, but a search of this site http://trove.nla.gov.au/ could prove useful, George.

One or two interesting paragraphs I will quote though, as follows:


from The Daily News (Perth WA) Wed 4th December 1907:

A BLIND MUSICIAN, MR MARTIN HENDERSON.
Traveling to Melbourne on board the RMS Omrah which passed through Fremantle today was a gifted musician in the person of Mr Martin Henderson. Although blind, Mr Henderson is a most wonderful player of the concertina, and is now about to enter into an engagement with Mr Harry Rickards for a tour throughout Australia. "I never in all my life", said Mr Herbert Fleming to a Daily News representative on the mail boat this afternoon, "listened to such sweet and beautiful music as supplied by this blind performer. He played for us right from the time of leaving Tilbury, and so entertained and delighted were the passengers by his playing that they subscribed a large sum. (A) portion of this will go (to)purchase a medal for Mr Henderson, and the balance is to be sent to his wife in England."


and from The Kalgoorlie Miner (WA) newspaper, Thursday 9th April 1908, where his repertoire and performance is described in some detail

Another newcomer was Martin Henderson. The same providence
that deprived him of his eyesight endowed him with remarkable musical gifts, and he deserved success, for he commanded it by virtue of his undoubted talent. The English concertina in his hands was a musical instrument in the truest sense of the term. There have been concertina and accordeon players galore on the variety stage. Few,if indeed any, have excelled Martin Henderson. He proved himself a thorough master of the instrument, with which his name is indelibly
associated.

Directly he commenced to play the audience recognised the hand of a master. They were hushed to silence, and a pin could have been heard fall while he played 'The Lost Chord' with superb skill. His soft and delicate, yet withal firm touch of the keys, and his manipulation of the instrument generally produced sweet sounds, the like of which have rarely been heard here. The people were spell-bound by the wonderful melody, and when the. last strains had ebbed away the applause was vociferous and genuine. Then he played a brief solo upon the piano, after which he gave a duet of exceeding beauty upon the piano and the concertina. He swept the keys of the former with his left hand and manipulated the concertina with his right. Having bowed in response to augmented applause, he illustrated medley methods in the use of the concertina, choosing 'The Blue Bells of Scotland' for
his theme. 'Variations,' according to the Maccabee in the old days,'consist of the worrying of a tune.' Variations with Martin
Henderson, only made the tune more delightful. His melodious rendering, was so heartily appreciated that he was compelled to submit to an encore, for which he gave an imitation of a church organ. His voluntary was excellently given. His illustration of the ringing of church bells was decidedly realistic, and his imitation of a school bell was droll in the extreme. The audience could 'Hear the Pipers Calling' when he reproduced Scottish bagpipe music upon the concertina, for which he obtained another recall. Martin Henderson scored heavily with patrons in all parts of the house.

So it would appear that Martin Henderson's repertoire consisted of similar material to that of his contemporaries, the likes of Prof Maccann and others who took a light classical approach to the music hall and variety stage of the period. Whether he had any "folk" influence to his playing is probably unlikely, but again, some of the top violinists of today's classical scene delight in playing jazz or bluegrass on their "days off"....

Apologies for the length of this post, but as the OP seems not to be a subscriber here, I am unable to send a PM.