Have just put up another story on Something To Look Forward To. The germ of this one is a memory of operating a Grand Master lighting board in my youth. Lovely picture below of the one that used to be in the Theatre Royal Brighton. They were amazing objects: levers, dials, wheels and entirely manual. Felt like operating a submarine. Also as each lever controlled a light there were occasions when you had to hit levers simultaneously with feet, knees, hands and chin! There were always hand holds in the ceiling above so we could swing monkey like to hit the right levers on cue.
Also in my research I came across A Bozze
In Italy in the seventeenth century they put a concave bottle in front of the candles they used to light the stage and filled them with different coloured liquids. The device both focussed the light and coloured it. There was a list of the best liquids to achieve specific colours. Unsurprisingly the majority of the liquids are alcoholic. Waste not want not? Time for a colour change – a normal cue – must have had a whole different dimension! Also if you look at the image you can see that the Bozze is mounted on a circular plate and that on the left is a metal screen, so by turning the plate you dim the light. Clever eh?
Amazing all the effort we humans put into creating illusion, casting shadows on the wall, trying to keep the darkness under our control.