This is a re-typeset copy of the original (1961) book, revised with
reference to the 1987 edition, with corrections to any errors I have
found, and modification to any formatting I found confusing. Page
numbering, line formatting, and font have been otherwise, faithfully
followed. Referenced external texts have been copied from the referenced
sources, and inserted after the main text. This was originally a pdf
Ebook, with embedded audio, taken from the recordings reference, and
indeed specially produced by Gael-Linn. The copyright of this book still
belongs to Hodder and Stoughton, but permission to publish has been
granted, see inside back pages, on the basis that they consider the work
to be obsolete, and superseded, and so they have no further financial
interest in it.