1.
Thomas Harriot Summer Series
Introduction
Friday, June 18, 2021

2.
Thomas Harriot
(1560-1621)
Brief biography
2
1560: Born in Oxfordshire
1577: Matriculates at Oxford (St Mary’s Hall: Oriel College)
from 1580: Humphrey Gilbert (to ‘83), Walter Raleigh
1584: First Virginia voyage
1585-6: Harriot in Virginia (Roanoke)
1588/90: A brief and true report of the New Found Land of
Virginia
from c. 1593: Henry Percy, 9th Earl of Northumberland. →
Sion House
1597: First optical experiments
July 22, 1601: discovers “law of refraction”
1603: Raleigh imprisoned in Tower
1605: Northumberland imprisoned in Tower
1606-9: Harriot writes to Kepler about refraction
July 1609: Makes first ever telescopic map of the moon
July 1621: Dies after long illness

3.
Harriot’s Manuscripts

4.
Harriot’s Manuscripts
● Rediscovered 1784, in Petworth House (seat of the
Egremonts, successors to the Percys, Earls of
Northumberland).
● Papers of “modern interest” separated by Franz von Zach.
● Harriot said to anticipate and surpass both Galileo and
Kepler.
● Debacle of attempted publication in Oxford at Clarendon
Press.
See Jackie Stedall, “Thomas Harriot (1560-1621): History and Historiography”
4

5.
1794-8: Verdict of Abraham Robertson,
Savilian Professor of Geometry
“Every thing depending upon the composition and resolution of forces is
so much better understood, and more clearly treated, since the
discoveries of Sir Isaac Newton, that it would suffer much upon
comparison with modern publications. The subject is more fully and
elegantly handled in Keill’s Introduction to Natural Philosophy.
[The papers on] the spots of the sun. I do not think that Harriott ever
intended them for publication; nor do I think that the publication of them
now would either satisfy rational curiosity, or contribute, in the smallest
degree, to the advancement of astronomy.
Upon the whole it is my opinion that the publication of the papers
mentioned in this report could only tend to prove that Harriott was very
assiduous in his mathematical studies, and in his observations of the
heavenly bodies; it could not contribute to the advancement of science.”
5

6.
Current State of Manuscripts
● Zach’s “significant” papers returned to Petworth House (where
they still are).
● Remainder (the vast bulk) donated to British Museum (BL);
divided into 8 volumes along subject lines: MSS Additional
6782-9.
● Other material found in BL in Harley fondo; and in Bodleian
Library, Rigaud fondo.
● Papers in Sion College (now in Lambeth Palace).
● Until recently, only place to see all papers (almost) together:
University of Delaware Special Collections, Shirley collection.
6

7.
Modern publications
● Committee formed in 1975 to publish a 7-volume edition
of Harriot’s papers.
● Editions of small treatises found among the papers (on
collision of bodies)
● Matthias Schemmel: The English Galileo: Thomas
Harriot’s work on motion as an example of preclassical
mechanics
● Janet Beery and Jackie Stedall: Thomas Harriot’s
doctrine of triangular numbers: the “Magisteria magna”
(interpolation methods)
7

8.
Front page of Harriot project (hosted at MPIWG)
8

9.
Matthias Schemmel’s “maps”
9

10.
The top-level “maps”
10

11.
Exploring some of the mathematical papers
11

12.
A network of manuscript pages
12

13.
Manuscript and text view
13

14.
Full manuscript view ...
14

15.
… in extraordinary resolution
15

16.
Harriot the Explorer

17.
Harriot teaches navigation to Raleigh’s sailors (1595 and 1584)
MS Add. 6788, fol. 491
17
“How to know your course to
sayle to any place assigned;
& in sayling to make true
recconing to find where you
are at any time; & how farre
from any place desired.”

18.
Everyday life in Virginia
Watercolor by John White (1585/6)
18

19.
Watercolors by John White (1585/6)
19
Everyday life in Virginia

20.
20
The Harriot/White Map of Virginia
White’s Watercolor de Bry’s Engraving

21.
“Most things they saw with us, as Mathematical instruments, sea compasses,
the virtue of the loadstone in drawing iron, a perspective glass whereby was
shown many strange sights, burning glasses, wildfire works, guns, books,
writing and reading, spring clocks that seem to go of themselves, and many
other things that we had, were so strange to them, and so far exceeded their
capacities to comprehend the reason and means how they should be made
and done, that they thought they were rather the works of gods than of men,
or at the leastwise they had been given and taught us of the gods. Which
made many of them to have such opinion of us, as that if they knew not the
truth of god and religion already, it was rather to be had from us, whom God
so specially loved than from a people that were so simple, as they found
themselves to be in comparison of us. Whereupon greater credit was given to
that we spoke of concerning such matters.” (A brief and true report, 1588)
21
Harriot: Science and Imperialism in the New World

22.
Harriot’s algebraic phonetic alphabet for the Algonquin language
22
MS Add. 6782, fol. 337r

23.
Westminster School
23
1585 version in papers of Richard Busby
An universall Alphabet conteyninge six & thirty
letters, whereby may be expressed the lively
image of mans voyce in what language soever;
first devised upon occasion to seeke for fit
letters to expresse the Virginian speche. 1585.
Beginning of Lord’s
Prayer
“Matthew Royden” (a poet, and one of
Harriot’s friends from Oxford, and
through the early 1580s)

24.
MS Add. 6789, fol. 390
24
Harriot’s “cipher”
“An yris videtur
in punkto
yunionis - No.”
(“Is a rainbow
seen at the
point of union?
No.”)

25.
Harriot the Mathematical Explorer

26.
A desire to find a way to the interior of things …
26
MS Add. 6789, fol 336

27.
27
… and to transform messy reality into algebra and calculation
Giulio Parigi, Palazzo degli Uffizi, c.
1600
MS Add. 6789, fol. 116

28.
Seeing the world through a mathematical lens
28
MS Add. 6788, fols 411r-v

29.
Harriot on the Burning Mirror
29
MS Add. 6789, fol 390

30.
MS Add. 6789, fol 116
30
Harriot’s innovation: a “functional” approach

31.
MS Add. 6789, fol. 116v
31
Mathematics and the imagination
“If the sun’s diameter were
2° 46′ 40″, it would burn up
everything on earth.
I should give some thought
to this question: how big
would the apparent
diameter be in the sphere
of Venus and Mercury?”

32.
1. How many people fit on the globe?
2. Mr Bulkeley’s Glass: Refraction, mathematics, and the imagination
3. Mapping the Moon
4. Billiard Balls: Collision and Stacking – mathematical model making
5. Conic sections – tools for exploring mathematics and nature
6. Binary numbers, combinations – and divination
Themes of the next six meetings