Most of Lovecraft’s science writings deal with astronomy, but he also had an avid interest in chemistry. Many of these essays may be found in Collected Essays, Volume 3: Science from Hippocampus Press. Dates are first publication dates unless otherwise indicated.

• The Art of Fusion, Melting, Pudling & Casting (written probably 1899)
• Chemistry; 4 extant volumes (written probably 1899)
• A Good Anaesthetic (written probably 1899)
• The Scientific Gazette; 32 issues (written 4 March 1899 to January 1909)
• The Railroad Review (written December 1901)
• My Opinion as to the Lunar Canals (written probably 1903)
• The Rhode Island Journal of Astronomy; 69 issues (written 2 August 1903 to February 1909)
• Astronomy/The Monthly Almanack; 9 issues (written August 1903 to February 1904)
• The Planet (29 August 1903)
• The R.I. Journal of Science & Astronomy (written 27 September 1903)
• Annals of the Providence Observatory (written 1904)
• Providence Observatory: Forecast for Providence & Vicinity Next 24^h (written 5 April 1904)
• The Science Library; 3 extant volumes (written probably 1904)
• No Transit of Mars (written 27 May 1906; 3 June 1906)
• Trans-Neptunian Planets (written 15 July 1906; 25 August 1906)
• The Moon (written 26 November 1903 and revised 24 July 1906)
• Astronomy Articles for the Pawtuxet Valley Gleaner (27 July to 28 December 1906)
• Astronomy Articles for the Providence Tribune (1 August 1906 to 1 June 1908)
• The Earth Not Hollow (written 6 August 1906; 12 August 1906)
• Does “Vulcan” Exist? (written probably late 1906; 1945)
• Third Annual Report of the Prov. Meteorological Station (written 16 January 1907)
• Celestial Objects for All (written 28 July 1907)
• Astronomical Notebook (written 1 September 1909 to 1915; October 1949)
• Venus and the Public Eye (written 24 December 1909; 26 December 1909)
• Astronomy Articles for the Providence Evening News (1 January 1914 to 2 May 1918)
• Science versus Charlatanry (9 September 1914)
• The Falsity of Astrology (written 8 October 1914; 10 October 1914)
• Astrology and the Future (13 October 1914)
• Delavan’s Comet and Astrology (written 24 October 1914; 26 October 1914)
• The Fall of Astrology (written 15 December 1914; 17 December 1914)
• [Isaac Bickerstaffe’s Reply] (21 December 1914)
• Mysteries of the Heavens Revealed by Astronomy (16 February to 17 May 1915)
• Editor’s Note to “The Irish and the Fairies” by Peter J. MacManus (February 1916)
• Brumalia (December 1916)
• The Truth About Mars (Autumn 1917)
• The Cancer of Superstition (written after 31 October 1926; 1966)
• [Some Backgrounds of Fairyland] (written probably 23 September 1932; 1944)