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232 and cataclysms in general is catastrophic so far as it assumes that these were brought about by causes which have now no parallel."

This was the earliest system of doctrine in geology, and was inevitable because of the narrow and false ideas concerning past time. Observation accumulated evidences of vast changes in the earth's crust; it was held that the world is but a few thousand years old; it was therefore concluded that the changes must have been on a stupendous scale, of which we have at present no experience.

There are geologists who still hold to this view, as there were those in the early history of the science who believed in vast time and slow changes. Hutton, in his theory of the earth, in 1795, put forth this advanced principle: "I take things such as I find them at present, and from these I reason to that which must have been." It, however, became the work of Sir Charles Lyell to elucidate and establish this doctrine, by extensive and critical investigations, as a broad and fundamental generalization of geological science. Uniformitarianism, or the theory which extends the present rate of terrestrial changes into the past, is a problem of geological dynamics, and involves the study of the totality of forces by which the earth's crust has been altered, and the rocky systems formed.

To work out so vast a subject on the basis of observation and immediate physical data was enough to task the largest capacity, and it is not surprising that Sir Charles Lyell was little disposed to venture into the more speculative questions of the science. Indeed, geologists early insisted on the necessity of limiting inquiry to the changes that have taken place since the formation of the earliest stratified rocks, and crucifying the propensity to pry into the more distant origin of the world. The English Geological Society tacitly forbade these speculations, and of this procedure Mr. Huxley says: "Uniformitarianism, as we have seen, tends to ignore geological speculation in this sense altogether. The one point the catastrophists and the uniformitarianists agreed upon, when this Society was founded, was to ignore it. And you will find, if you look back into our records, that our revered fathers in geology plumed themselves a good deal upon the practical sense and wisdom of this proceeding. As a temporary measure, I do not presume to challenge its wisdom; but in all organized bodies temporary changes are apt to produce permanent effects; and, as time has slipped by, altering all the conditions which may have made such mortification of the scientific flesh desirable, I think the effect of the stream of cold water, which has steadily flowed over geological speculation within these walls, has been of doubtful beneficence."

Mr. Huxley, in common with many other scientists, now holds that the progress of geological thought must carry us beyond uniformitarianism into evolutionism.

But Sir Charles Lyell is the farthest possible from being a narrow-minded partisan. His career offers one of the noblest examples of