Longitude Legends: Nevil Maskelyne

This week's Longitude Legend is one of my favourite characters from the longitude story: Nevil Maskelyne. He was played by Samuel West against Michael Gambon's John Harrison in the TV miniseries Longitude, based on Dava Sobel's book Longitude : the story of how a lone genius solved the greatest scientific problem of his time. In her chapter on Maskelyne, Sobel begins 'A story that hails a hero must also hiss at a villain'. But was Maskelyne really a villain?

Well, luckily for us there is a new book that has recently appeared on the shelves of the Ships, Clocks & Stars gift shop: Maskelyne: Astronomer Royal, an edited volume by our very own Rebekah Higgitt that explores many facets of Maskelyne's life (and in far more detail than I have space to go into here).

Nevil Maskelyne (1732–1811) was born in Kensington Gore in 1731. After attending the Westminster School, he studied mathematics at Trinity College, Cambridge. He became a fellow of the Royal Society in 1758 at the age of just 26.


Nevil Maskelyne, by Mary Byrne Nevil Maskelyne, by Mary Byrne, 1801 (NMM ZBA5688)

In 1761 the young astronomer, Nevil Maskelyne, tested Tobias Mayer’s lunar tables on a voyage to St Helena in the South Atlantic. He became a lifelong champion of the lunar-distance method. Two years later Maskelyne published The British Mariner’s Guide, a handbook which contained new versions of Mayer’s tables and instructions for observing and calculating longitude.

The British Mariner’s Guide Nevil Maskelyne, 1763 The British Mariner’s Guide Nevil Maskelyne, 1763

In September 1763, he set sail in the Princess Louisa to test both astronomical methods. Christopher Irwin accompanied him with two of his marine chairs. Six months later John Harrison’s son, William, left for Barbados on board the Tartar with H4. After landing at Barbados, Maskelyne made further observations to help assess the methods. In early 1765 the Board met again to discuss the trial results.

You can see Harrsion You can see Harrsion's H4 on display in our Ships, Clocks & Stars exhibition

Accurate and regularly updated astronomical tables were needed for both timekeeper and lunar-distance calculations of longitude. The Act of 1765 instructed the Board of Longitude to produce an annual ‘Nautical Almanac’ of astronomical tables for use at sea. As Astronomer Royal from 1765, Nevil Maskelyne oversaw the collection and processing of data for these tables from the Royal Observatory at Greenwich.

Maskelyne and his assistant undertook the observations at Greenwich. He then directed the considerable mathematical work required to turn the observational data into usable tables. This laborious task was done by a network of human ‘computers’ and ‘comparers’ across the country. The results were published as the Nautical Almanac and the Tables Requisite to be used with the Astronomical and Nautical Almanac.

From the British Mariner's Guide to the  Nautical Almanac, everything Maskelyne did was a step towards making the life of ordinary navigators easier. All of which was very noble, but is only part of the reason for my fondness for the fifth astronomer royal. The other reason I feel so kindly towards Maskelyne is currently on display in Ships, Clocks & Stars: his observing suit.

Waters in Maskelyne

Maskelyne spent every night on the Observatory making observations, and it isn't warm at night, up a hill. He complained to his brother-in-law, who was stationed in India, about the cold, and he sent him over the beautiful striped silk which now makes-up this tremendous two-sie.

When the conservators first got their hands on this, they found lots of small holes and evidence of wear and tear, which suggests that Neville loved wearing this suit-and you can see why. It's padded both for warmth and comfort, and it has integral feet. They didn't find any mud or anything on the feet, so he probably had wooden clogs or overshoes that he would wear over them. And the idea of the Astronomer Royal padding across the Meridian courtyard in his two-sies and wooden clogs is, in my book, enough to make him a Longitude Legend.

To see the observing suit first hand, Ships, Clocks & Stars is open daily until 17.00. Rebekah Higgitt's Maskelyne: Astronomer Royal is on sale now.