A limelight - the first theatrical spotlight
The Scottish engineer Drummond invented the limelight in 1816. He used a core of limestone (calcium) that was heated to incandescence by a burning mixture of oxygen and hydrogen. The incandescent limestone provided very brilliant light that could be directed and focused.
The limelight was first employed in the theatre in 1855 and became widely used by the 1860s. Its intensity made it useful for spotlighting and for the realistic simulation of effects such as sunlight and moonlight. It could also be used for general stage illumination. The greatest disadvantage of the limelight was that it required constant attention of an individual operator, who had to keep adjusting the block of limestone as it burned and to tend to the gas that fuelled it.
