HELMHOLTZ. 1 



By T. C. Mendenhall. 



Hermann Ludwig Ferdinand, Baron von Helmholtz, was born in Pots- 

 dam on August 31, 1821. In 1842 he received bis degree in medicine at 

 Berlin, and entered tbe Government service as an army surgeon. In 

 1847 be published his essay on the Conservation of Energy. In 1849 

 he was appointed professor of physiology at Bonn. In 1851 he invented 

 the ophthalmoscope. In 1855 he was made professor of anatomy and 

 physiology at Bonn. In 1859 he was appointed to the same chair at 

 Heidelberg. In 1880 he was made one of the foreign members of the 

 Boyal Society of London. In 1803 he published his great work on the 

 Sensations of Tone. In 1866 the first edition of his Physiological 

 Optics was completed. In 1871 he was made professor of natural 

 philosophy at the University of Berlin. In 1873 he received from the 

 Eoyal Society the highest distinction which it can bestow, the Copley 

 Medal; and iu the same year the King of Prussia conferred upon him 

 the Order of Merit in Science and Art. In 1883 hereditary nobility 

 was conferred upon him by Emperor William I. In 1887 he assumed 

 the directorship of the great Physico-Technical Institute, founded by 

 the German Government at Charlottenberg. In 1891 tbe seventieth 

 anniversary of his birth was celebrated with great ceremony, and he 

 was placed at the head of the civil list by the German Emperor. In 

 1893 he visited America, serving as president of the International 

 Electrical Congress held in Chicago. In 1894, on September 8, he 

 died at the age of 73 years. 



Such is the brief outline of the life of one of tbe most extraordinary 

 men of the present century. To perfect such a sketch in anything like 

 just proportions, or to attempt in the few minutes allotted to me to- 

 night to set forth anything like a fair estimate of tbe labors of one of 

 whom it may be justly said that he was the most accomplished scholar 

 of modern times, is a task no one would seek. Nor can one easily 

 decline tbe honor which is carried by an invitation from a commission 

 representing the scientific societies of Washington to take part in so 

 memorable a commemoration as this. Under the circumstances, I must 



'Read at a memorial meeting under the auspices of the Joint Commission of the 

 Scientific Societies at Washington City, January 14, 1896, Reprinted from Science. 

 New series, Vol. Ill, No. 58, February 7, 1896. 



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