The Componium has been discussed a couple of times in the MMD over the
years.  I set off searching for a copy of the Van Tiggelen book on the
same subject and eventually found one.  In the process of my search
I asked www.abebooks.com to let me know when a copy was available for
sale.  Today I received email with the following information:

  VAN TIGGELEN PH. J.
  Componium. The mechanical musical improvisor
  Inst. Sup. d'Archiologie et d'Histoire de l'Art, Louvain-la-Neuve,
  1987. 1 vol. br, 17x26, 462 pp., nbr. ill. Bookseller Inventory #332
  Price: US$ 43.50 (Convert Currency)
Bookseller: Bouquinerie de l'Escargon, Redu, Belgium

I pass this along as I have already found a copy and thought someone
else might be interested.

John Haskey