At the Leeds Meeting of the British Association in 1890, my old friend Professor A. H. Green delivered an address to the Section which has generally been regarded as expressing an opinion adverse to the use of the science of geology as an educational agent. Some of the expressions used by him, if taken alone, certainly seem to bear out this interpretation. For instance, he says: “Geologists are in danger of becoming loose reasoners”; further he says: “I cannot shut my eyes to the fact that when geology is to be used as a means of education there are certain attendant risks that need to be carefully and watchfully guarded against.” Then he adds: “Inferences based on such incomplete and shaky foundations must necessarily be largely hypothetical.”

Such expressions, falling from an accomplished mathematician and one who was such an eminent field geologist as Professor Green, the author of some of the most trustworthy and most useful of the Geological Survey memoirs, and above all one of the clearest of our teachers and the writer of the best and most eminently practical textbook on physical geology in this or any other language, naturally exercised great influence on contemporary thought. And I should be as unwise as I am certainly rash in endeavouring to controvert them but for the fact that I think he only half believed his own words. He remarks that “to be forewarned is a proverbial safeguard, and those who are alive to a danger will cast about for a means of guarding against it.