On the death of Berzelius in 1848, it was to Liebig that every chemist looked for a continuation of the annual Report on the progress of chemistry, which had now become the central magazine of facts, whither each worker in the science could resort to make himself acquainted with what had been done by others on any subject which he proposed to investigate. From that time to the present day Liebig's _Annalen_ has been the leading chemical journal of the world. Of the other literary work of Liebig--of his essays, his celebrated "Chemical Letters," his many reports, his severe and sometimes harsh criticisms of the work of others--of the details of the three hundred original papers wherein he embodied the results of his researches, I have not time, nor would this be the place, to speak. Honoured by every scientific society of any note in the world, crowned with the highest reward which England and France can offer to the man of science who is not an Englishman or a Frenchman--the Copley Medal and the associateship of the Institute--honoured and respected by every student of science, loved by each of the band of ardent natures whom he had trained and sent forth to battle for the good of their race, and, best of all, working himself to the last in explaining the wonders of Nature, he "passed into the silent land" on the 18th of April 1873, leaving the memory of a life nobly devoted to the service of humanity, and the imperishable record of many truths added to the common stock of the race. * * * * * The life-work of Dumas, other than that which I have already sketched, is so manifold and so varied, that to do more than refer to one or two leading points would carry us far beyond the limits within which I have tried to keep throughout this book. In one of his earliest papers Dumas adopted the atomic theory as the corner-stone of his chemical system; he was thus led to an experimental revision of the values generally accepted for the atomic weights of some of the elements. Among these revisions, that of the atomic weight of carbon holds a most important place, partly because of the excellency of the work, but more because of the other inquiries to which this work gave rise.