It requires an imaginative feat to understand how strange it was in the first decades of the twentieth century for a young secretary – such is his usual volunteer – to hear for the first time in her life her own disembodied voice. Seeing the reactions wrought by the sound is like witnessing the effects of real magic.

The audible astonishment that follows that coup de théâtre is the cue for Vincenzo’s encore: he pulls back the spring-loaded brass footplate to release the recorded cylinder and then erases the recording using the shaving wheel – sometimes housed in a separate unit, but on the Imperator concealed beneath a hatch inside the main cabinet. Behold: the voice has vanished!

Only one of his demonstrations deviates from this pattern. On this occasion, Mr Notovitch stays Vincenzo’s hand as he opens the hatch. Notovitch announces that he has no intention of shaving the cylinders. ‘I intend to make a record,’ he says. ‘A record of my life.’

So, of the twenty-one cylinders that survive of Nicolas Notovitch, the first is that one. The recording appears to have degenerated, but this is an auditory illusion; our ears, accustomed to high-fidelity sound and Dolby noise reduction, are spoiled. This hissing, scratchy recording projects a dead man’s low, faintly Eastern European voice into the present day.

‘Four score and seven years ago our fathers brought forth, on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.’

There is a gap of a few seconds, and then, a little querulously, the voice enquires: ‘Is that sufficient for your purpose, Mr Dittami?’

*

THE FOLLOWING WEEK, Mr Notovitch sends a scrawled note to the office asking for Vincenzo by name. His handwriting is very crabbed and difficult to decipher, but the note appears to say that the machine is giving him difficulties, which he does not specify.

That Saturday, Vincenzo returns alone and repeats his demonstration. Notovitch is, as on that first visit, watchful, imperious, guarded. When Vincenzo asks him to try loading the cylinder, he turns his back on the younger man, and wrestles with the mechanism in vain. Vincenzo can hear that he’s struggling to release the catch of the footplate. He offers to oil it.

‘The problem, Mr Dittami,’ Notovitch huffs, ‘is not one of oil.’ He straightens up with a visible effort and extends his empty hands. The fingers are splayed and lumpy like the toes of a frog. ‘You see? I suffer badly from arthritis in your climate. I simply cannot operate this device. Please make arrangements to remove it.’

It is true, Vincenzo concedes, that the mechanism of the Imperator is sometimes initially stiff, but it will yield after a period of moderate usage. No great strength is required to work it; for this reason, he adds, the model is extremely popular with lightly built female employees. His words fail to mollify the client.