Its not often you see a mechnical calculator these days. Obsolete for over 25 years the functionality they provided can now be included on your wrist watch.
Its incredible to think that this was type of instrument that was used to design concorde or the 747. To modern eyes its large, heavy and cumbersome, but the quality of the engineering is all apparent. It still works and makes a wonderfuly satisfying sound when the keys are pressed and the handle turned.
Lack of ink in the printer ribbon precludes us from working out exactly what the buttons do. What exactly does 'triangle' and 'diamond' mean on the operator switch ?
But its wonderfully tactile and satisfyingly noisy.
Pics and sound here.