Therefore my success as a man of science whatever this may have amounted to has been determined as far as I can judge by complex and diversified mental qualities and conditions. Of these the most important have been the love of science unbounded patience in long reflecting over any subject industry in observing and collecting facts and a fair share of invention as well as of common sense. With such moderate abilities as I possess it is truly surprising that I should have influenced to a considerable extent the belief of scientific men on some important points.