While much may be done by individual students, it is less to their single efforts than to the combined investigations of many fellow-workers that I look most hopefully for the accumulation of data towards the determination of the present rate of geological changes. I would, therefore, commend this subject to the geologists of this and other countries as one in which individual, national, and international co-operation might well be enlisted. We already possess an institution which seems well adapted to undertake and control an enterprise of the kind suggested. The International Geological Congress, which brings together our associates from all parts of the globe, would confer a lasting benefit on the science if it could organise a system of combined observation in any single one of the departments of inquiry which I have indicated or in any other which might be selected. We need not at first be too ambitious. The simplest, easiest, and least costly series of observations might be chosen for a beginning. The work might be distributed among the different countries represented in the Congress. Each nation would be entirely free in its selection of subjects for investigation, and would have the stimulus of co-operation with other nations in its work. The Congress will hold its triennial gathering next year in Paris, and if such an organisation of research as I have suggested could then be inaugurated a great impetus would thereby be given to geological research, and France, again become the birthplace of another scientific movement, would acquire a fresh claim to the admiration and gratitude of geologists in every part of the globe.[97] FOOTNOTES: [71] Presidential Address to the Geological Section of the British Association for the Advancement of Science at the Dover Meeting 1899. [72] _Theory of the Earth_, vol. i. p. 108. [73] _Op. cit._, vol. i. p. 173, _note_. [74] _Op. cit._, vol. ii. p. 329. [75] _Op. cit._, vol. i. p. 200. [76] _Theory of the Earth_, vol. ii. p. 205. [77] _Op. cit._, vol. i. p. 44. [78] _Illustrations of the Huttonian Theory_, § 118. [79] _Trans. Roy. Soc. Edin._, vol. xxiii. (1862). [80] _Proc. Roy. Soc. Edin._, vol. v. p. 512 (Dec. 18, 1865). [81] _Trans. Geol. Soc. Glasgow_, vol. iii. (February, 1868), pp. 1, 16. [82] 'The Age of the Earth,' being the Annual Address to the Victoria Institute, June 2, 1897. _Phil. Mag._, January, 1899, p. 66. [83] _Recent Advances in Physical Science_, p. 174. [84] Presidential Address. _Quart. Journ. Geol. Soc._, 1869. [85] _Trans. Geol. Soc. Glasgow_, vol. iii. (March 26, 1868), p. 189. Sir W. Thomson acknowledged my adhesion in his reply to Huxley's criticism. _Op. cit._, p. 221. [86] Darwin's _Life and Letters_, vol. iii. pp. 115, 146. [87] _Rep. Brit. Assoc._, 1886, p. 517. [88] _Nature_, vol. li. p. 585, April 18, 1895. [89] _Rep. Brit. Assoc._, 1886, p. 518.