Thomas Jefferson Papers

Thomas Jefferson to George F. Hopkins, 5 September 1822

To George F. Hopkins

Monticello Sep. 5. 22.


Your letter of Aug. __ was recieved a few days ago. of all the departments of science no one seems to have been less Advanced, for the last hundred years than that of Meteorology. the new Chemistry indeed has given us a new principle of the generation of rain by proving water to be a composition of different gasses, and has aided our theory of Meteoric lights. electricity stands where Dr Franklin’s early discoveries placed it, except with it’s new modification of Galvanism. but the phænomena of snow, hail, halo, Aurora Borealis, haze, looming Etc are as yet very imperfectly understood. I am myself an empyric in Natural philosophy, suffering my faith to go no further than my facts. I am pleased however to see the efforts of hypothetical speculation because by the collisions of different hypotheses truth may be elicited and science advanced in the end. this sceptical disposition does not permit me to say whether your hypothesis for looming and the floating volumes of warm air occasionally percieved may or may not be confirmed by future observations. more facts are yet wanting to furnish a solution on which we may rest with confidence. I even doubt as yet whether the looming at sea and at land are governed by the same laws. in this state of uncertainty I cannot presume either to advise or discourage the publication of your essay. this must depend on circumstances of which you must be abler to judge your self; and therefore1 I return the paper as requested with assurances of my great respect.

Th: J[e]ff[erson]

PoC (DLC); signature faint; at foot of text: “Mr George F. Hopkins.” Printed in Hopkins, Observations on Electricity, Looming, and Sounds; together with a Theory of Thunder Showers, and of West and North West Winds (2d ed., New York, 1825), 38. Enclosure: enclosure to Hopkins to TJ, [received 29] Aug. 1822.

The new chemistry is the name commonly given to Antoine Laurent Lavoisier’s eighteenth-century reformulation of the field by disproving the theory of phlogiston, explaining combustion, and establishing a systematic chemical nomenclature (W. F. Bynum, E. J. Browne, and Roy Porter, eds., Dictionary of the History of Science [1981], 299).

Hopkins’s hypothesis for looming was that it was “occasioned solely by the agency of the sun operating on vapour.” He believed that floating volumes of warm air arose almost exclusively in lowlands; that larger ones contained more heat than their smaller counterparts; and that, although they were infallible precursors to a thunderstorm, they never occurred immediately after one (Hopkins, Observations, 8–10, 14, quote on p. 14).

1Text from “in this state” to this point not in Hopkins, Observations.

Index Entries

  • books; on meteorology search
  • chemistry; new theories search
  • electricity; study of search
  • Franklin, Benjamin; science of search
  • galvanism; study of search
  • Hopkins, George Folliet; letter to search
  • Hopkins, George Folliet; Observations on Electricity, Looming, and Sounds (written as “Hortensius”) search
  • Jefferson, Thomas; Books & Library; receives works search
  • Jefferson, Thomas; Books & Library; sends manuscripts search
  • Jefferson, Thomas; Opinions on; phenomenon of looming search
  • Jefferson, Thomas; Opinions on; truth search
  • Lavoisier, Antoine Laurent; theories of search
  • looming, phenomenon of search
  • meteorology; TJ on search
  • meteorology; works on search
  • natural philosophy; TJ on search
  • Observations on Electricity, Looming, and Sounds (“Hortensius” [G. F. Hopkins]) search
  • water; chemical composition of search
  • weather; hail search
  • weather; heat search
  • weather; rain search
  • weather; snow search
  • weather; thunderstorms search