Professor von Helmholtz, the greatest of the German mem of
science, died at Charlottenburg on Sunday, the immediate cause of death being an attack of apoplexy. The Professor was seventy-three years old, having been born at Potsdam. on August 31st, 1821. The world will remember him most• by his far-reaching discovery of the ophthalmoscope,—the instrument by which the youngest practitioner is now able to tell more about the condition of a patient's vision than. could the most skilful oculist of the last generation. The- ophthalmoscope allows the doctor to look into the human. eye and see the exact condition of the nerves and blood- vessels. It substitutes certainty for guesswork. But though. the world at large will bless the brain and hand which did so much for the most precious of the human senses, the men• of science will probably declare that Helmholtz did even great work in the regions of pure science, and in his studies of sensation and voluntary motion. One of his greatest dis- coveries was in the region of sound, He first fully analysed and set forth the vibrations which form the basis of music. A writer in the Times declares him to have been to science what Goethe was to literature. " Breadth, universality of comprehension and sympathy, and a certain unmistakable intellectual serenity are characteristic of both." Like Goethe, too, Helmholtz found that philosophic calm led on to worldly victory. He was honoured by his countrymen and by all Europe, and ten years ago the German Emperor raised him to the ranks of the hereditary nobility,—a very rare honour in a country where caste-feeling reigns supreme.