It all began with the music box, although it was the barrel organ, with its pinned wooden barrel and manually-cranked system of bellows, valves and triggers that really set the ball rolling. This was replaced by a less cumbersome system involving perforated paper and pneumatic bellows (operated by pedals or an electric motor) which formed the basis of almost all the fascinating automatic music machines that found their way into homes and cafes throughout Europe and America at the turn of the century.
Among the most intriguing, even macabre, items in the Brentford collection is a self-playing Steinway Duo-Art grand piano, which reproduces the exact performances of famous pianists such as Rachmaninov and Myra Hess. Its mechanism could record expression as well as individual notes, so the pianist had simply to sit down and play for the instrument to be able to reproduce every nuance of his or her performance. The master recordings, on paper rolls, were then sold in their thousands to owners of automatic pianos. Most were thrown out, along with the pianos themselves, when radio and gramophones came in, but enough were saved for the Musical Museum to have a library of more than 20,000 reproducing rolls for a variety of automatic instruments.
"Even in the age of CDs and laser discs, it still thrills people to see a piano or an organ playing itself," says Michael Ryder, chairman of the museum's trustees. Even more thrilling are the elaborate orchestrelles and orchestrions, which imitate whole orchestras, and the fiendishly complicated Violano-Virtuoso and the Phonoliszt-Violina, which play real violins, clearly visible behind glass. Never mind the sound quality, just admire the technical wizardry.
Equally impressive are the Fotoplayer (one of only six left in the world) which provided music and sound effects, such as tom-toms, gun-shots, howling gales and engine whistles, for silent films, and the "Mighty Wurlitzer" cinema organ, which takes up 400 square feet of floor space, can imitate more than 150 different instruments and sound effects and was the star attraction at the Regal Theatre, Kingston upon Thames, during the 1930s.
Housed in a crumbling disused church overlooking the River Thames at Brentford, which became its "temporary" home more than 30 years ago, the collection probably the most extensive in the world was started by a single enthusiast, Frank Holland, in the late 1950s. Horrified by the way these rare and enchanting instruments were being neglected, dumped in skips and even donated to piano-breaking competitions, he gave up a flourishing career in engineering to devote himself to their restoration and preservation. Since his death in 1989, the museum has been run by volunteers and administered by a board of trustees.
Recommended for children of 12 and up, a normal 90-minute tour includes a demonstration of all the main types of instrument, plus an explanation of how they worked, who owned them (they were found in humble dwellings as well as grand houses) and why.
The museum will also tailor tours for younger children and adapt them to national curriculum projects on, say, the history of recorded music, Life in Victorian Britain or the physics of sound. To mark the 100th anniversary of the moving image this year, the museum has had a summer exhibition of old projection equipment and cinema posters.
There's also a handling collection of small musical boxes and automatic table-top instruments which the museum is happy to take into schools before an arranged visit, to introduce the whole idea of musical instruments that play themselves.
The Musical Museum, 368 High Street, Brentford, Middlesex TW8 0BD. Tel: 0181 560 8108. School parties by arrangement, April to October. Approach in writing first. Adults Pounds 3.20, children Pounds 2.50.