RECENT GEOGRAPHICAL PROGRESS. 37 



nary friction produces heat then and there upon the surfaces rubbed, 

 while the force expended in overcoming the electric attraction may- 

 be converted into a spark which shall appear a thousand miles away 

 from the place where it was generated. 



Theoretic conceptions are incessantly checked and corrected by 

 the advance of knowledge, and this theory of electric fluids is doubt- 

 ed by many eminent scientific men. It will, at all events, have to be 

 translated into a form which shall connect it with heat and light, be- 

 fore it can be accepted as complete. Nevertheless, keeping ourselves 

 unpledged to the theory, we shall find it of exceeding service both in 

 unraveling and in connecting together electrical phenomena. 



RECENT GEOGRAPHICAL PROGRESS. 1 



By Chief-Justice DALY, 



PRESIDENT OF THE GEOGRAPHICAL SOCIETY. 



THE year 1875 completed the third quarter of the nineteenth cen- 

 tury, a period distinguished by the activity which has prevailed 

 in every branch of scientific inquiry, but particularly distinguished as 

 a remarkable period of geographical exploration and discovery. 



The history of geographical knowledge is a history of its rapid 

 acquisition in periods very limited in point of time, but of great activ- 

 ity, and of long intervals of repose, in which comparatively little was 

 done, or a great deal lost that had been previously acquired. For 

 the last twenty-five years we have been living in one of those periods 

 of exceptional activity, for at no time has an interest so wide-spread 

 been manifested for geographical exploration since that great age of 

 maritime discovery, that began in the early part of the fifteenth cen- 

 tury with the exploration of the western coast of Africa by the Por- 

 tuguese, and culminated in the circumnavigation of the globe by 

 Magellan. The comparatively small limits of about a century is all 

 that is embraced from the time (1418), when Prince Henry of Portu- 

 gal, surnamed the Navigator, took up his abode upon the promontory 

 of Sagres to devote the residue of his life to the fitting out of expedi- 

 tions for the exploration of the coast of Africa beyond Cape Bojador, 

 a region then wholly unknown, and the year 1519, when Magellan 

 entered the Pacific by the discovery of the straits that bear his name. 

 Within that period the captains of Prince Henry had sailed around 

 the continent of Africa ; Columbus had discovered America ; his com- 

 panion, Nunez de Balboa, the Pacific ; Sebastian Cabot had followed 



1 From advance-sheets (introductory portion) of the President's annual address be- 

 fore the American Geographical Society, on " The Geographical Work of the World in 

 1875." 



