, Louis J. M. See vol. iv., p. 70.

Historique et description des procedes du daguerreotype et du diorama,
Paris, 1839. (This was translated into English.)

Dalton, John. See vol. iv., p. 40.

"On the Absorption of Gases by Water," read before the Literary
and Philosophical Society of Manchester, October 21, 1803. This
was published in 1805, and contains the atomic weight of twenty-one
substances, some of which were probably added, or corrected, between the
date of the first reading and the publication.

Davy, Sir Humphry. See vol. iv., pp. 48, 209.

"Some Chemical Agencies of Electricity," in Phil. Trans, for 1806, vol.
viii. Researches, Chemical and Philosophical, chiefly concerning Nitrous
Oxide or De-phlogisticated Nitrous Air and its Respiration, London,
1800.

Dewar, James. See vol. v., p. 39.

"Solid Hydrogen," in Proc. Roy. Inst, for 1900. "The Nadir of
Temperature and Allied Problems " (Bakerian Lecture), Proc. Roy. Soc,
1901.

Dufay, Cisternay. See vol. ii., p. 267.

Histoire de l'Academie Royale des Sciences, between 1733 and 1737,
contains Dufay's principal papers.

Eulbr, Leonard (1707-1783). See vol. iii., p. 17.

Lettres a une Princesse d'Allemagne sur quelques sujets de physique et
de philosophie, St. Petersburg, 1768.

Faraday, Michael. See vol. iii., p. 241.

On the Induction of Electric Currents, in Phil. Trans. of Royal Society
for 1832, pp. 126-128. Explication of Arago's Magnetic Phenomena, by
Michael Faraday, F.R.S., Phil. Trans, of Royal Society for 1832, pp.
146-149. Franklin, Benjamin. See vol. ii., p. 286.

New Experiments and Observations on Electricity, London, 1760.

Galvani, Luigi (1737-1798). See vol. iii., p. 229.

De viribus electricitatis in motu musculari commentatio, Bologna, 1791.
This discovery of Galvani was first brought to notice by Volta's famous
paper to the Royal Society, entitled "An Account of some Discoveries
made by Mr. Galvani, of Bologna," published in the Phil. Trans, for
1793, pp. 10-44.

Gay-Lussac, Joseph Louis. See vol. iv., p. 41.

Memoire sur la combinaison des substances gazeuses, Mem. Soc. d'Arcueil,
1809.

Halley, Edmund. See vol. iii., p. 7.

An Account of Several Extraordinary Meteors or Lights in the Sky, in
Phil. Trans., vol. xxix., pp. 159-162, London, 1714. Helmholtz, H. L. F.
See vol. iii., p. 280.

Handbuch der physiologische Optik, Leipzig, 1867.

Joule, J. P. See vol. iii., p. 269.

On the Calorific Effects of Magneto-E