INTRODUCTION. 



11 



that which historical representations in gener- 

 al can hope to achieve. Details, whether as to 

 the form or arrangement of natural things, no 

 more than in reference to the struggles of man 

 with the elements, or the wars of one nation 

 against another — all, in short, that falls within 

 the sphere of mutability and true accident — can- 

 not be derived or built up from h priori concep- 

 tions. The natural history of the earth, and 

 universal history, consequently, stand on the 

 same grade of the empirical ladder ; but a lu- 

 minous treatment of either, a rational arrange- 

 ment of natural phenomena and of historical 

 incidents, impresses us deeply with a belief in 

 an old inherent necessity, which rules all the 

 operations both of the spiritual and material 

 forces within circles eternally reproduced and 

 only periodically contracted or enlarged. This 

 necessity, indeed, is the very essence of nature ; 

 it is nature herself, in the two spheres of her 

 being — the material and the spiritual — and it 

 leads to clearness and simplicity of view, to the 

 discovery of laws which, in experimental sci- 

 ence, present themselves as the ultimate term 

 in human inquiries. 



The study of every new science, especially 

 of one which embraces the infinite field of cre- 

 ation, the universe at large, may be compared 

 to a journey into a foreign country. Before 

 undertaking such an expedition in company, 

 we inquire as to its feasibility ; we measure our 

 own powers of endurance, and we look with a 

 suspicious eye at the powers of our intended 

 companions, with the perchance unjust anxie- 

 ty lest they prove impediments in the way. 

 But the times in which we live diminish the 

 difficulties of the enterprise, and my confidence 

 in ultimate success is based on the brilliant po- 

 sition now occupied by natural science itself, 

 whose increasing stores may now be said to 

 add less to the amount than to the enchain- 

 ment of observation. The general results, 

 which so powerfully interest every cultivated 

 mind, have been wonderfully augmented since 

 the end of the eighteenth century. Facts now 

 stand less insulated ; numerous gaps between 

 different orders of beings and phenomena have 

 been filled up ; points which had remained in- 

 explicable to the inquiring spirit at home, with- 

 in the narrower circle of experience accessible 

 to it, are frequently made clear by journeys un- 

 dertaken into the remotest regions of the earth. 

 Vegetable and animal forms that long appeared 

 isolated, now appear connected by intermedi- 

 ate links or transition forms. A general con- 

 catenation, not in simple linear directions only, 

 but in reticulate or more intricate modes, ac- 

 cording to the higher development or the ar- 

 rest of certain organs, according to relative pre- 

 ponderance in the several parts or systems, now 

 presents itself to the mind of the enlightened 

 naturalist. Appearances of stratification in tra- 

 chytic syenite or porphyry, in green stone and 

 serpentine, which are doubtful in Hungary, so 

 rich in gold and silver, in the platina districts 

 of the Ural chain, or deeper into Asia, in the 

 south-western Altai, are unexpectedly cleared 

 up by geological observations in the lofty pla- 

 teaus of Mexico and Antioquia, and in the val- 

 leys of Choco. The materials which universal 

 geography employs are not indiscriminately ac- 

 cumulated. In the present times, in virtue of 



the tendency which their individual character 

 impresses upon them, it is admitted that new 

 facts are only pregnant with future good, when 

 the traveller is familiar with the actual state 

 and requirements of the science whose bound- 

 ary he pretends to widen ; when ideas, in oth- 

 er words, insight into the spirit of nature, guide 

 the taste for observation and collection. 



Through this direction of the study of nature, 

 through the happy, but, at the same time, often 

 too readily satisfied taste for general results, 

 can a very considerable portion of natural sci- 

 ence be made the common property of cultiva- 

 ted humanity, and this with a full sense of the 

 import and form, of the grandeur and worth of 

 the subject, altogether different from that pop- 

 ular science which was held sufficient for the 

 world at large up to the end of the last centu- 

 ry. Let him, therefore, whom circumstances 

 permit to escape from time to time from the 

 narrow circle of his every-day occupations, la- 

 ment that he has " remained so long a stranger 

 to nature, unconscious of her charms," and 

 learn, that in the contemplation of her grandeur 

 and freedom, there dwells the purest delight 

 which exalted intelligence can obtain for man. 

 The study of general natural science, indeed, 

 awakens organs in our interior that have long 

 slumbered. We enter upon a new and more 

 intimate intercourse with the external world, 

 and are brought to feel a larger sympathy with 

 that which proclaims at once the industrial 

 progress, and the intellectual improvement of 

 mankind. 



The clearer the insight we obtain into the 

 connection of phenomena, the more readily do 

 we emancipate ourselves from the error of 

 believing that every department of natural 

 knowledge is not equally important in the cul- 

 ture and welfare of mankind, whether it be that 

 department which measures and describes, or 

 chemical inquiries, or the investigation of the 

 generally diffused physical forces of matter. In 

 the observation of a phenomenon which seems 

 at first to stand isolated and alone, there fre- 

 quently lies the germ of a great discovery. 

 When Galvani stimulated the nerves of sensa- 

 tion by the contact of two dissimilar metals, his 

 most intimate friends and contemporaries could 

 never have expected that the voltaic pile, with 

 its electricity of contaction, would one day 

 show us a brilliant metal in the alkalis, silvery 

 in its appearance, readily inflammable, and so 

 light as to float upon the surface of water ; that 

 the same arrangement would by and by become 

 the most powerful instrument in analytical 

 chemistry, and prove at once a thermoscope 

 and a magnet. When Huyghens began to in 

 vestigate the optical properties of double re 

 fracting spar, no one imagined that the phe 

 nomena of coloured polarization would lead oni 

 of the singularly clear-sighted natural philoso 

 phers of our day('*) to discover in the fragmen 

 of a mineral a means of knowing whether thi 

 light of the sun proceeded from a solid mass 04 

 from a gaseous canopy ; whether comets havo 

 the power of emitting light in themselves, or 

 merely reflect the light they receive from other 

 sources. 



A like respect for every department of the 

 study of nature is, however, especially neces- 

 sary in the present times, when the material 



