Composers perform. But Dal Segno does not say from which of the three electrically driven, but incompatible, systems – Welte-Mignon, Ampico and Duo Art – these rolls were produced. Playback is through ‘a brand new piano in a digital recording’, though the recording isn’t always satisfactory. The sound becomes shallow at high dynamic levels.

Not every composer is distinguished. Richard Strauss certainly is and his three recordings illustrate a point about this method of recording: what seems an amateurish performance doesn’t necessarily indicate an amateurish performer. Strauss is expressive and accomplished in Auf stillen Waldespfad but the excerpts from Salome are unsensuous or effortful. The discrepancy could be the result of poorly adjusted mechanisms, or shrinkage in ageing paper rolls.

There are two identifiable errors: what’s listed as John Ireland’s Ragamuffin on track 22 is Amberley Wildbrooks, while the following track, presumably meant to be Ragamuffin, is a repeat of Cyril Scott’s Chinese Caprice on track 14. Despite provisos, however, many of the rolls and systems appear unscathed by time and offer bewitching experiences, not least the sort of deep-toned pianism that isn’t often heard today – a reminder that, whatever the shortcomings, this medium is also a part of gramophone history.