424 JOHN WILLIAM DRAPER. 



on a journey of exploration into North Africa, — one pregnant result 

 reached being the conclusion that the Sahara was a former sea-basin 

 elevated at a later epoch. Desor distinguished three kinds of deserts : 

 erosion-deserts, sand-deserts, and those of plateaux. 



Desor was one of the most active pioneers in prehistorical investi- 

 gations. He made a costly collection of archaeological treasures, and 

 he published, between 1861 and 1881, eleven papers upon the subject, 

 the last being on the fossil man of Nice. When the first International 

 Congress of Anthropologists and Archaeologists met at Neuchatel, in 

 1866, he was chosen to preside. Desor owned a country-seat on 

 the summit of the Jura, which was the resort, in the summer, of the 

 learned from every country. The names of his famous visitors are 

 inscribed on a tree a century old ; among them that of Theodore 

 Parker. Having given the best of his life to science, progress, and 

 freedom, Desor bequeathed to the city of Neuchatel his rich collec- 

 tions in geology and archjeology, and also a large property, which he 

 had inherited from his brother's wife, to preserve and increase them. 



JOHN WILLIAM DRAPER. 



John William Draper was born at St. Helen's, near Liverpool, 

 on May 5, 1811. At the age of eleven he was sent to the school of 

 the Wesleyan Methodists, his father being a minister in that denomi- 

 nation. Here and under private tutors he received his elementary 

 education. After the University of London was opened he went there 

 to study chemistry under Dr. Turner. At the age of twenty-two 

 (1832), he was brought by his American relatives to the United 

 States, where he afterwards lived, and where he died on Jan. 4, 

 1882, in his home at Hastings, on the Hudson. In this country he 

 studied in the University of Pennsylvania, and in 1836 took the degree 

 of Doctor of Medicine. He had already published original papers in 

 the Journal of the Franklin Institute, — in 1834, on the Nature of 

 Capillary Attraction, and on the Best Form of Galvanic Batteries ; in 

 1835, on the Magnetic Action of Light. In 1836 the thesis presented 

 for his degree was published by the Faculty of the University. After 

 this, many contributions to science followed in rapid succession, — on 

 chemistry, electricity, heat, light, thermo-electricity, phosphorescence, 

 and kindred subjects. Fifty different papers, published in this country 

 or in Europe, and many of them in several places, are enumerated in 

 the Catalogue of the Royal Society of London which closes with the 

 year 1863. 



