On our way through Tasmania we stopped off in the small mining town of Zeehan. Primarily to check out the West Coast Pioneer Memorial Museum. Chock full of mining paraphernalia, photos of dusty towns and dudes with axes, soil maps the likes of which would make Bldgblog cream itself, spiky minerals and this ancient photocopier:

Tracing paper is placed against the glass cylinder, sensitised paper then placed over the top of the tracing paper and the canvas blind drawn around the cylinder to keep the two pieces of paper in close contact. The arc light is then switched on and allowed to travel slowly down the centre of the cylinder. After exposure, the sensitised paper is removed, washed and dried. The final print is your classic white lines on blue paper, blueprint.

I am led to believe that the machine is still in good working order.