Mirror unit

The mirror unit is an item of hired event equipment: a full-length mirror which shows the subject their own reflection, photographs them, and then displays the photograph in the same frame. It is documented here because of the log it produced at one hiring, and not for anything it was hired to do.

The hiring

The unit was engaged as a miroir magique for a bar mitzvah in Montpellier and delivered the previous afternoon. The hire company's docket records it as returned in working order, and the fault described below was not reported to them at any point.

The fault

Each track in the playlist was played one semitone above the one before it. The effect is that of a truck driver key change applied without regard to where a song ends, and applied again to the result, so that by the fortieth track the material is five tones above its recorded pitch and by the sixty-first it is no longer identifiable by ear.

Guests are recorded, in the operator's note on the docket, as having taken this for a feature of the evening.

The order of play

What makes the log worth keeping is not the fault but the sequence. The playlist follows no arrangement the hire company recognises: not the order supplied by the family, not alphabetical, not by year.

Three consecutive entries read Hard-Fi, Escobar, Wakefield. The second is not a track title and the third is not an artist, and the three appear in this order in a list that has been identified as a page of unrelated provenance carried in the unit's setup folder.

This is the fifth case of the practice set out under External ordering, and the first in which the borrowed sequence and the thing ordered survive together in one document. In the four earlier instances one or the other had to be inferred; the case has accordingly been described as the best evidence for the practice and, by one commentator, as the worst, on the ground that a single well-documented instance is what one would expect a coincidence to look like.

Relation to the other instances

The setup folder is not the Composite sheet, but the resemblance has been remarked on: a page of names of mixed kind, no heading, carried loose, used for its order and not for its content. Whether the operator knew that the page was being read as a playlist is not recorded, and he has not been asked.

The Ordering source in this case is at least still attached to what it ordered, which is not true of any of the others.

Status

The unit was returned and re-hired eleven times before the log was noticed, and has not been examined since. The log survives as a printout because the operator kept it, and he kept it, he has said, because of the pitch and not because of the order.

See also

• Composite sheet — Composite sheet, External ordering, Ordering source
• External ordering — External ordering, Ordering source
• Levernet Rhapsody — Composite sheet, External ordering
• Misdirected enquiries — Composite sheet, Mirror unit
• Route document — Composite sheet
• Kilometre reading