Monday, 11 November 2013



British Library Additional Manuscript Vol. 37203
Babbage's Papers on Astronomy

[Note Babbage did not provide titles for the lectures. These have been ascertained from their content.]

Lecture 1:         BL Add. Ms. 37203 ff34-69
Introduction to  and History of Astronomy, from Thales to Copernicus
The primacy of Astronomy amongst the physical sciences - Utility of Astronomy: commerce and navigation - Newton's astronomical method of ascertaining historical dates, e.g. dating of the expedition of Jason and the Argonauts, Xerxes invasion of Greece - Origins of Astronomy: the Chaldean Zodiac - The Ancient Greeks - Thales of Miletus: heights of pyramids, calendars and prediction of eclipses - Gnomons: Anaximander and Manilius - Anaximenes and Anaxagoras - Pythagorean school - On the Greek calendar and the Metonic cycle - Eudoxus and his theory of concentric spheres - Archimedes and Aristarchus - Hipparchus: the length of the solar year, path of the Moon, distances of the Moon and Sun from the Earth, cataloguing of the Stars - Posidonius and his disciple Cleomedes: magnitude of the Earth, terrestrial climates, refraction - Ptolemy: his catalogue of the Stars, on the Ptolemaic system of the Universe, his Almagest - The Dark Ages - Arabic Astronomy - Caliph Almamon - Importance of Arabic astronomical records even for present-day study of Astronomy - Spanish Astronomers - Alphonsus, King of Castille: Alphonsine Tables - The Renaissance - Purbach and Regiomontanus: new translations of Ptolemy's Almagest and the Greek Astronomers - Toscanelli's plumb line and the measurement of the altitude of the Sun - Copernicus: his life and work, his recognition of the inconvenience of the Ptolemaic hypothesis, his observations leading to the publication of Celestial Revolutions.

Lecture 2:         BL Add. Ms. 37203 ff73-77
(Ms pages 1-18 of script of lecture missing, begins page 19, ends page 23, remainder of lecture missing)
On Astronomical Instruments
[Difficulties peculiar to Astronomy, and the means of obviating them - Plan to be pursued - Description of Instruments. On the Pendulum and the Measure of Time, its irregularities and the means of correcting them - The Astronomical Quadrant and Circular Instruments - Hadley's Quadrant - ] On the Sextant and its use for measuring angular distance - On the use of a mercury artificial horizon - [Transit Instruments].

[ff78-82 Unused printed subscription forms for the Cambridge Analytical Society the backs of which Babbage has used for notes.]

Lecture 3:         BL Add. Ms. 37203 ff83-103
Observing and Cataloguing the Heavens
On what Astronomers observe, and their hypotheses and the methods used by them  to confirm these - Division of the heavenly bodies into three types: Sun, Moon and Stars - On the apparent motion of the Stars in the heavens, circumpolar stars, Pole Star, Constellations, Planets  - On the isolation of the Earth in space: North and South Pole, Axis and Equator - The hypothesis of the crystalline sphere and its motion round a fixed Earth -Determination and use of a Meridian, 'Transiting the Meridian' - Sidereal Time - Mean Solar Time -  Right Ascension and Declination of an astronomical body - Origin of Degrees - History of star catalogues: Hipparchus', Flamsteed's, Maskelyne's and Lalandes' - On the Refraction of Light, its effect on observations - Terrestrial Refraction: two reports in Phil. Trans. - Dr. Wollaston's  and Monge's theories - Mirages.

[ff104-112 mathematical notes. Copy made by CB of Newton's Principia, section 11 from Corollary 6 proposition 66 to the end of the 17th Corollary.

Lecture 4[?]: (labelled "3rd" with comment by CB as "too short by ¬") BL Add. Ms. 37203 ff113-142
Ascertaining the Figure of the Earth
Lecture is principally on the discovery of the shape and magnitude of the Earth - On the rotation of the Earth on its axis and its isolation in space - Examples of a ship appearing from over the horizon and how canal diggers noted that, because of the curvature of the Earth, there is dip of 8" in the horizon every mile in length along the canal - "If Man had confined himself solely to the collection of facts science would have presented a barren detail of arbitrary names and he would never have attained the knowledge of the great laws of Nature. It is by comparing phenomena together and by endeavouring to trace their mutual connection, by gradually correcting his theory that he has succeeded in discovering these laws the existence of which may be perceived even in their most complicated effects." - That the diurnal motion of the heavenly bodies is only an apparent motion - Newton: his laws of motion and hypothesis that the Earth is not a perfect sphere, but flattened at the poles. Newton's laws of motion -  Galileo and his adoption of the Copernican theory: his subsequent trial for heresy at the hands of the Inquisition - 16th to 18th century attempts to measure the shape of the Earth: Fernel and the magnitude of Earth; Snellius (Snell) of Holland, his measurement of the distance of one degree of latitude between Alcmaer and Bergen op Zoom; Richard Norwood, his measure of the distance between London and York; Riccioli, his fraudulent measurements and numerous errors; AbbĂ© Picard. Richer's pendulum measurements at Paris and Cayenne - Newton's versus Descartes' views respectively on whether the Earth was flattened at the poles or not - French Academy of Science's expeditions to settle the question of the length of a degree of latitude - Mapertuis' expedition to Lapland - La Condamine's measurement of the length of 3« degrees of latitude at Quito in 1739 - Adventures of the expeditionists - As a result of these expeditions,

 "It was decided that the degrees diminish as we approach the equator and consequently that it (The Earth) is a flattened spheroid."

Lecture 5:         BL Add. Ms 37203 ff143-178
On the Moon
On months - On the appearances and phases of the Moon - On the reflectivity of the Moon's surface - On the motion of the Moon and its orbit - On Eclipses of the Sun and Moon, their causes -  On the dating of historical events using eclipses - How Dr. Halley estimated the date of Caesar's invasion of Britain as being the 26th August 3950 world time (55 bc) -  How people in France and Spain, even as late as the eclipse on 12th May 1706, were still superstitious about them - On other 18th century eclipses - On the use of the micrometer for measuring the apparent size of an astronomical body - On the Moon's apparent diameter and its variations in its orbit round the Earth - The fact that the Moon always shows the same face to observers on the Earth - The Moon's Libration and its causes - The fact that there are two librations: a latitudinal and a longitudinal motion - On the diurnal libration caused by optical parallax -  On the theory of tides - On the effect of the Moon and Sun on tides - On Spring tides and tidal bores - On the stability of the equilibrium of the oceans -  Laplace's analysis of tides - On deluges - Distance of the Moon from Earth - Diameter of the Moon - Force of Gravity on its surface - Appearance of the surface of the Moon: craters, on their possibility of being volcanoes - How to measure the width of craters - How Sir W. Herschel had observed, in May 1783, a volcano in action on the Moon, and again in March 1794 - On the question of whether there could be life on the Moon - The fact that the power of telescopes was insufficient to answer this question.

Lecture 6:         BL Add. Ms. 37203 ff179-213
On the Sun
On the proper motion of the Sun versus its apparent motion - Measurement of proper motion - On the observational origin of the Laws of Nature - That the proper motion of the Sun is retrograde with respect to the daily rotation of the Earth - On the Plane of the Ecliptic - How it gives rise to the seasons of the year - On the seasons: their climatic differences, Solstices and Equinoxes - Variations in the apparent diameter of the Sun - Distance from the Sun and  its measurement by parallax - On Sun Spots, their size and time of revolution - On the Sun Spot Belt - On the variations in the brightness of the Sun's disc - On the Sun's atmosphere - Zodiacal light: Cassini the elder's and Mairan's ideas - Measurement of Time - Astronomical or Solar Day - Equation of Time - On the question of whether the Earth moves round the Sun or vice versa - Arguments for - Rmer's discovery of the velocity of light from the occultation's of Jupiter's sattelites - Man's propensity to consider himself and the Earth at the centre of the Universe - Tidal effects in the Earth's atmosphere caused by the Sun - Patterns of the prevailing winds on the Earth - Halley's theory on the origin of the Trade Winds - The grazing comet theory of the origin of the planets, Buffon's views - Errors of this theory - On the cause of Sun Spots, Lalande's and others' theories - On the question of the origin of the Sun's power - Herschel's observation's of the Sun's Spots and its atmosphere and his methods of observing the Sun.

Lecture 7:         BL Add. Ms. 37203 f214 verso
The Inner Planets
Script Missing. No notes made other than it was to be on Observations on the planets Mercury, Venus, the transit of Venus, and Mars.

Lecture 8:         BL Add Ms. 37203 ff215-251
On the Minor Planets (Asteroids) and also the History and Development of the Reflecting Telescope
The singularity of interest of the 4 smaller planets beyond the orbit or Mars recently discovered in Babbage's time - The need for a telescope to observe them - On the History of the Titius[-Bode's] Law - Kepler's suppositions - That there appeared to be a gap or vacancy in-between the orbits of Mars and Jupiter suggeesting a new planet - Astronomers agree to make a planned search of the heavens - Piazzi's discovery of Ceres: confirmed by Gauss and Olbers - Orbit of Ceres - Impact of discovery on Astronomy - Olbers discovery of Pallas, its orbit - Harding's discovery of Juno - Olbers hypothesis on the origin of the Minor Planets: exploded planet theory - Consequences of this hypothesis - Discovery of Vesta - On the eccentricity and obliquity of the orbits of the Minor Planets - Final abandonment of the Zodiac of the ancients - Lagrange's calculations and likelihood of the exploded planet hypothesis - Size of the Minor Planets - Herschel's experiments and measurement, his estimates of their size.

History of the Reflecting Telescope - Mersenne's idea - Gregory's Optica Promota 1660 - Newton's design and models - Hadley's Reflecting Quadrant - James Short's telescopes - Herschel's work and his quantification of the power of a telescope: (i) Magnifying Power (ii) Space Penetrating Power - Effects of the weather and climate on the performance of a telescope.

Lecture 9: [Missing?]
The Outer Planets [conjectured title of lecture]
Presumably on the planets Jupiter, Saturn and Uranus, and the history of the discovery of the latter by Herschel.

Lecture 10:       BL Add. Ms. 37203 ff252-281  Draft, ff282-301 Top Copy
On the Scientific Method and the Theory of Universal Gravitation
"By observation and experiment we gain the first materials of our knowledge. These are the foundations of all philosophy." - The reason for scientific theory as a means of organising knowledge - Bacon's arguments against hypothesis countered by Newton - That the theories of Universal Gravitation and the Copernican System are examples of useful hypotheses - That the origin of the Copernican hypothesis lay in its beauty and simplicity - That the utility of hypothesis lay in its predictive power and testability by experiment - That hypotheses which had been superseded had been useful in their time - That some hypotheses were a historical necessity for progress - Kepler and his discovery of the elliptical shape of the paths of the Earth and planet round the Sun - Kepler's law: that the square of the tiem of any planet's revolution always bore a certain proportion to the cube of its distance from the Sun and that this ratio is a constant - Table for the planets - Kepler's view of the Sun's propensity for moving bodies, a power which spreads throughout space and moves rapidly - His hints that a force of gravity might exist - Descartes theory of vortices - Utility of Descartes' theory even though wrong - Newton's principles of Universal Gravitation - Origin of the theory lie with the Ancient Greeks: Anaxagoras, Democritus and Epicurus - Kepler and the Moon's tendency to fall towards the Earth - Hooke's letter to the Royal Society in 1666 anticipating Newton's theory - Newton's discovery of the theory when he was contemplating the fall of the Moon towards the Earth and asking whether the same law applied with the fall of bodies at the surface of the Earth - His first estimates in error because estimate of the size of the Earth in error, corrected when Picard's value for this was known - Newton's predictions published in Principia - On the admiration of his contemporaries - On Newton's personality - On his genius - Consequences of the Law of Universal Gravitation - Irregularities in the motion of planets Lagrange's and Laplace's extensions of the theory - On the stability of the Solar System - Argument for the existence of God from design.

Lecture 11:       BL Add. Ms. 37203 ff302-333
On Comets
Comets as distinct from stars and planets as astronomical phenomena - Ideas and theories of the Greeks - Tycho Brahe's  observations - Kepler's theories - The straight line motion hypothesis - Cassini - Helvetius and Hooke - The parabolic motion hypothesis - The Great Comet of 1680/81 - Doerfell and the elliptic motion hypothesis - Newton's theory of universal gravitation applied to Comets - On the composition of the tails of Comets - De Mairan - Halley's treatise on Comets (1705) - On the periodic return of various comets - Historical records - Origin of the Great Flood - Halley's prediction of the return of the comet named after him - Observations on the comet of 1759 - Calculations of the gravitational perturbation effects of Jupiter and Saturn on the path of the comet by Lalande, Clairaut and Mme. Lepante - Lexell and the discovery of another periodic comet - Terror caused by the comet of 1773 - Estimate of the tidal force caused by a close encounter of the Earth with a comet - Laplace's calculations - Composition of the nuclei of comets - Schroeter and Herschel views - The comet of 1811 - On the return and non-return of comets -Speculations on what happens to those which do not return.

Lecture 12: [Missing?] Beyond the Solar System [conjectured title of lecture]

William Herschel's 20 ft Reflecting Telescope