Perhaps it is a local colloquialism, such as is noted in the following newspaper clip from the Mariposa Gazette of 23 January 1901 on page four second column citing the London Chronicle as its source.The Brevity of Ballarat.It was in Ballarat that Mark Twain found the local language so puzzling at first, the good people of the place deeming life too short to dawdle in their talk. The mayor called on the American humorist and laconically said "K'm." Then when Mark Twain gave him a cigar he simply said "Q." Subsequent inquiry revealed that these terms were Ballaratese for "welcome" and "thank you."
 

    On Wednesday, March 14, 2018 2:23 AM, Scott Holmes <[log in to unmask]> wrote:
 

 Having found no reference to a Ballarat Fly, outside of fly-fishing in
Ballarat, I remain curious as to where Mark Twain came up with that
name for the railway known as the Napier Express.  Are there any known
Twain scholars in New Zealand that might have a clue?  Twain refers to
it both as the "Ballarat Fly" and "The Fly" in the first paragraph of
chapter 35.
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