THE LIFE OF EULER.
LETTER I. Of Magnitude, or Extension.
LETTER II. Of Velocity.
LETTER III. Of Sound, and Its Velocity.
LETTER IV. Of Consonance and Dissonance.
LETTER V. Of Unison and Octaves.
LETTER VI. Of Other Consonances.
LETTER VII. Of the Twelve Tones of the Harpsichord.
LETTER VIII. Of the Pleasure Derived from Fine Music.
LETTER IX. Compression of the Air.
LETTER X. Rarefaction and Elasticity of the Air.
LETTER XI. Gravity of the Air.
LETTER XII. Of the Atmosphere, and the Barometer..
LETTER XIII. Of Air-guns, and the Compression of Air in Gunpowder.
LETTER XIV. The Effect Produced by Heat and Cold on All Bodies, and of the Pyrometer and Thermometer.
LETTER XV. Changes Produced in the Atmosphere by Heat and Cold.
LETTER XVI. The Cold Felt on High Mountains and at Great Depths Accounted for.
LETTER XVII. Of Light, and the Systems of Descartes and Newton.
LETTER XVIII. Difficulties Attending the System of Emanation.
LETTER XIX. A Different System Respecting the Nature of Rays and of Light, Proposed.
LETTER XX. Of the Propagation of Light.
LETTER XXI. Digression on the Distances of the Heavenly Bodies, and on the Nature of the Sun, and His Rays.
LETTER XXII. Elucidations on the Nature of Luminous Bodies, and Their Difference from Opaque Bodies Illumined.
LETTER XXIII. How Opaque Bodies Become Visible. Newton's System of the Reflection of Rays Proposed.
LETTER XXIV. Examination and Refutation of Newton's System.
LETTER XXV. A Different Explanation of the Manner in Which Opaque Bodies Illuminated Become Visible.
LETTER XXVI. Continuation of the Same Subject.
LETTER XXVII. Conclusion: Clearness and Colour of Opaque Bodies Illuminated.
LETTER XXVIII. Nature of Colours in Particular.
LETTER XXIX. Transparency of Bodies Relative to the Transmission of Rays.
LETTER XXX. Of the Transmission of Rays of Light, through Transparent Mediums, and Their Refraction.