David MacMillan wrote:

> I've yet to find anything which explains the layout of an organ
> in terms which a novice can understand.

May I suggest he subscribe to the Fair Organ Preservation Society.  We
publish a quarterly magazine packed with articles about the history of
these instruments and their workings (including terminology explained
in plain English) and music.  Visit our web site on

    http://www.ndirect.co.uk/~fops/

John Page, Membership Secretary,
Fair Organ Preservation Society
memsec.fops@fops.ndirect.co.uk