Christie’s presents a curated group of scientific instruments that span the centuries from 1300-1976. These artefacts tell the story of the history of calculating and computing, beginning with the newly discovered ‘Chetwode’ horary Quadrant from the 14th century through to the iconic Apple-1 that heralded the revolution in home computing.

This rare and important medieval horary quadrant would have been used to calculate the time of day by observing the height of the Sun, it is based on mathematical principles developed by Islamic science in 10th century Baghdad. The transmission of ancient knowledge into Renaissance Europe resulted in some of the finest crafted scientific instruments that survive. The astronomical instruments from the Early Modern period demonstrate the artistry of the instrument maker as well exemplify how knowledge of calculating methods was held by their users.

With the Industrial Revolutions in Europe came the mechanisation of instrumentation. Here we offer a group of mechanical calculators that are in working order and can perform multiplication calculations in a fraction of the time it would have taken to do manually before their invention.

Entering the 20th century another sale highlight is a rare Enigma cipher machine, the cracking of whose code by Alan Turing and the teams at Bletchley Park resulted in the development of the ‘colossus’, the world’s first programmable computer. We end the sale with the iconic symbol of home computing, the revolutionary Apple-1, the first product of the world’s biggest company.