SEVENTEENTH AND EIGHTEENTH CENTURIES 191 



by Henrik Steffens, who, although he has played little part in the develop- 

 ment of biology, nevertheless deserves mention here owing to his importance 

 in cultural history. Born at Stavanger, in Norway, he studied in Copen- 

 hagen and Kiel and after a period of wandering came to Jena, where he be- 

 came an enthusiastic admirer of Schelling, a friend of Oken, and a natural 

 philosopher heart and soul. He returned to Copenhagen in 1802. and for a year 

 or two lectured at the University, but as he obtained no permanent post 

 there, he accepted an appointment in Germany, where he remained for the 

 rest of his life. During the years he spent in Denmark he exercised great in- 

 fluence by his enthusiastic promulgation of natural philosophy, although his 

 exaggerations aroused doubts in the minds of the Danes, which were not 

 perceived by his less critical friends in Germany. His principal work on 

 natural philosophy dealt with the internal natural history of the earth; in it 

 he seeks to prove, inter alia, that the various strata of the earth are sections 

 of a galvanic element. Of importance to the history of biology was his theory 

 of the origin of the circular coral islands; he believed that they grew up on 

 the edge of volcanic craters in the ocean, and this theory was accepted as true 

 by many, until Darwin disproved it by his well-known investigations into 

 the subject. 



In Sweden natural philosophy was embraced by the famous Carl Adolf 

 Agardh (1785-1859), known as one of Sweden's most many-sided geniuses. 

 He was a native of Scania, matriculated at Lund, and eventually became 

 lecturer in mathematics and professor of botany and economics at that 

 University. He ended by being Bishop of Karlstad, after having won renown 

 as a botanist, mathematician, national economist, priest, and politician. 

 Only his sphere of activity as the first belongs to this narrative. At Lund 

 Agardh became acquainted with the Linn^an system of plant classification, 

 and in the course of journeys in Germany he came to know Schelling and 

 natural philosophy. His most lasting fame he has won as one of the founders 

 of alga; classification; much of the system that he created still exists today. 

 He has also made valuable contributions in connexion with plant classifica- 

 tion as a whole; in particular he was one of the first to pronounce against the 

 sharp difference that had hitherto been held to exist between phanerogams 

 and cryptogams. His general views with regard to animate nature he has col- 

 lected in a handbook of botany published in the years 1818-32., the first part 

 of which he dedicated to Schelling. This first part, entitled "Organography," 

 contains also traces of the influence of natural philosophy; nevertheless 

 Agardh displays a degree of caution in speculation that is in favourable 

 contrast to the rashness of his German master. Thus he at once declares on 

 the first page that natural objects cannot be exactly defined on a logical basis; 

 he believes that we have to content ourselves with establishing in each what 

 is the most common phenomenon or the most usual form, without venturing 



