The Monument in London was built to be giant telescope that would prove Earth orbited the Sun

Sarah Knapton

Standing majestically on the site of the first church destroyed by the Great Fire of London, and topped with a gilded urn of fire, The Monument is a testament to the great rebuilding of the capital that took place after the 1666 conflagration.

Yet the towering fluted Doric column was not intended to be merely a reminder of past misfortunes. It was designed to show London was looking firmly towards the future, and more importantly to the stars.

The Monument was built as a giant telescope, heralding a burgeoning scientific age, where new knowledge would rise from the ashes of the past.

Early drawings showing how the telescope was to be used, have recently gone on display at a new permanent gallery at London’s Science Museum, which charts how the capital grew to lead the world in scientific endeavours. 

“The Monument was intended to be used as a scientific instrument,” said Alexandra Rose, lead curator of Science City 1550–1800: The Linbury Gallery.

“It really says something about the state of science at this time that they could build a huge telescope right in the heart of London. The scientists planned to sit at the bottom and look at the stars through a hatch in the top.

“It was supposed to be used like a zenith telescope - designed to point straight upwards - and they had an idea of using it to see the stellar parallax.

“In practice it didn’t work well because there was a lot of movement from carriages going past.”

Print and model of Monument in Science City Credit: Science Museum Group Jody Kingzett

Monument, which is officially called The Monument To The Great Fire of London, was designed by the English philosopher and polymath Robert Hooke and Sir Christopher Wren, and built between 1671 and 1677 on the site of St Margaret’s Church, Fish Street. 

Constructed from Portland stone, it stands at a height of exactly 202 feet, to mark its distance from the shop of Thomas Farriner, on Pudding Lane, where the blaze began. But Hooke and Wren wanted their creation to be more than just a memorial to the calamity.

An original drawing of The Monument Credit: Paul Grover for the Telegraph

By the middle of the 17th century, many scientists had come round to Copernicus' idea that Earth orbited the Sun once a year. Yet if that was the case then stars should appear to exhibit a back-and-forth motion caused by the changing perspective of the Earth at is swung around the Sun - known as a parallax 

Despite countless attempts, the parallax remained an elusive target, and detractors of the Copernican theory claimed the inability to observe the phenomenon proved it was untrue.

Hooke and Wren hoped the great proof would come using The Monument telescope. London had become renowned for its manufacturer of scientific instruments and by the second half of the 17th century, craftsmen were able to make a living just creating technical equipment for astronomy and experiments.

Yet scientists at the time did not understand the vast distances of the stars and did not have the telescopes that could measure their minute movements as the Earth orbited the Sun. An annual stellar parralax was not successfully measured until 1838 when German Friedrich Bessel captured the faint wobble of star 61 Cygni.

But Monument continued to be used as a scientific instrument. The internal steps – each measuring exactly six inches tall – enabled barometer readings at different heights.

These experiments were described in Philosophical Transactions, the journal of the Royal Society. 

The idea of using London as a working laboratory even extended to St Paul’s where some claimed Wren had designed the central dome so high to allow for pendulum experiments.

The new gallery has brought together objects from the Science Museum Group Collection, King’s College London’s King George III collection, and objects and artworks lent by the Royal Society. 

Spanning 250 years of scientific development in the capital it features objects such as Sir Isaac Newton’s paradigm shifting work, 'Principia Mathematica', which laid out the laws of universal motion, alongside his opus 'Opticks', and his own reflecting telescope of 1671 which was used to illustrate the principles of light and reflection.

The Monument to the Great Fire of London, United Kingdom Credit: Alamy

Visitors will also see a microscope designed by Hooke, who was also the Royal Society’s Curator of Experiments and a copy of his ground-breaking Micrographia. 

Hooke’s close-up drawings of insects and plants viewed through his microscope astonished the scientific community and public when they were published in Micrographia in 1665. The book marked the first use of the term “cell” and became the first scientific best-seller. 

There are also a pair of celestial globes from 1599, designed by Willem Janszoon Blaeu, a cartographer for the Dutch East India Trading Company created at a time when Amsterdam eclipsed London on the world stage. The gallery charts the changes that repositioned the city as a world power. 

Visitors in front of Dutch terrestrial globes by Willem Janszoon Blaeu Credit: Jody Kingzett, Science Museum Group

Sir Ian Blatchford, Director of the Science Museum Group, said: “We now have a permanent space in the museum to display some of the most beautiful and historically significant objects in our collection, and tell this fascinating story of how London helped shape science and, in turn, how science helped shape the city during this period.”

Science City 1550–1800: The Linbury Gallery is is free to visit and opened to the public this month.