Date of Publication: 29 January 2020
If you’ve ever visited Cambridge and wandered down Trumpington Street, you’ve probably caught glimpse of something rather bold and unusual and thought… ‘what is that grasshopper clock?’
Known as the Corpus Clock – it hasn’t stood the test of time like many other famous Cambridge historic gems – having only been inaugurated in 2008. As a relatively new feature, it certainly stands out against the historic brickwork with its gold plated face, with many dubbing it as ‘the strangest clock in the world.’
We take a brief look at the making of this dazzling piece of engineering.
Firstly, a few facts…
- The ripple design alludes to the Big Bang, with the centre considered to show the beginning of time.
- The ‘grasshopper’ that sits atop is actually a ‘Chronophage,’ which means time-eater, devouring each minute as it passes with a jaw that snaps shut.
- The clock has no digital numbers or hands, making it difficult on first glance to be able to tell the time. However, there are three LED rings which show the hours, minutes and seconds. These are only expected to last around 25 years, and so the clock will need regular servicing.
- When an hour strikes, there is no chime. Instead, passers-by will hear the shaking of chains and a hammer hitting a wooden coffin. A rather morbid sound, it represents the passing of time which ultimately leads to death. This is reinforced by the Latin inscription which sits underneath the clock – ‘mundus transit et concupiscentia eius,’ meaning ‘the world and its desires pass away.’
1725: English inventor, John Harrison invents the grasshopper escapement – a mechanical cog-like device which helps to regular a clock’s pendulum movement and reduce incorrect time readings.
1999: In 1999, John C Taylor, one of Cambridge’s horologist alumni and inventor of the kettle returned to the city for the first time after having graduated in 1956. Having seen that his college – Corpus Christi – hadn’t changed in the 40 years since he was there, he offered the college the funds to transform the (once before) bank into a brand new library. To mark the occasion, Taylor also decided to add the iconic Corpus Chronophage which would occupy the old bank’s front door.
2001 – 2008: Working closely with local engineers, Huxley Bertram, Taylor and the team worked on the construction of this impressive clock over seven years.
On his website, John C Taylor details his initial ideas for the clock:
‘I was inspired to create the Chronophage because of modern art. I’ve never been a fan of it, so I wanted to create something that was modern art but had a bit more to it. I wanted to find a new way of telling time.
My idea with the Chronophage was to turn the clock inside out, and then make the tiny little escapement and the grasshopper into the biggest gear on the clock. I wanted impact so I made it one and half metres in diameter, with the grasshopper a metre long on the top and its legs were the pallets of the escapement which John Harrison designed. This means you can actually see the grasshopper escapement working.’
The clock’s intricate and very particular design stretched engineering ability, with part of it having to be engineered underwater at a secret Dutch military research institute. A science student at Varsity (the University of Cambridge’s student newspaper) describes how the clock’s mechanisms works;
‘Escapements form the central mechanism of all traditional clocks. After being wound, the escapement serves to push the pendulum slightly, with each swing moving the clock forward by a fixed amount. Since the pendulum’s swings are necessarily of the same length, no matter how far out the pendulum swings, this period will stay the same, ensuring that the clock keeps good time. Before Harrison, most escapements were fairly crude. His invention, the grasshopper escapement, cut down massively on friction by using two pivoted arms, which give the impression of something creeping round the edge of the clock, hence the name.’
2008: The clock is unveiled by renowned physicist Stephen Hawking, who wrote the groundbreaking book, A Brief History of Time.
Want to visit this magnificent artefact? Check out our Cambridge summer courses and you could be in the city this summer!