author's preface. 



!)f those portioxis of my discourses which have been preserved 

 by the industry of certain attentive auditors. With the ex- 

 ception of the first forty pages, the whole of the present work 

 was written, for the first time, in the years 1843 and 1844. 



A character of unity, freshness, and animation must, I 

 think, be derived from an association with some definite 

 epoch, where the object of the writer is to delineate the pres- 

 ent condition of knowledge and opinions. Since the addi- 

 tions constantly made to the latter give rise to fundamental 

 changes in pre-existing views, my lectures and the Cosmos 

 have nothing in common beyond the succession in which the 

 various facts are treated. The first portion of my work con 

 tains introductory considerations regarding the diversity in 

 the degrees of enjoyment to be derived from nature, and the 

 knowledge of the laws by which the universe is governed ; it 

 also considers the limitation and scientific mode of treating a 

 physical description of the universe, and gives a general pic- 

 ture, of nature which contains a view of all the phenomena 

 comprised in the Cosmos. 



This general picture of nature, which embraces within its 

 wide scope the remotest nebulous spots, and the revolving 

 double stars in the regions of space, no less than the telluric 

 phenomena included under the department of the geography 

 of organic forms (such as plants, animals, and races of men), 

 comprises all that I deem most specially important with re- 

 gard to the connection existing between generahties and spe- 

 cialities, while it moreover exemplifies, by the form and style 

 of the composition, the mode of treatment pursued in the se- 

 lection of the results obtained from experimental knowledge. 

 The two succeeding volumes will contain a consideration of 

 the particular means of incitement toward the study of na- 

 ture (consisting in animated delineations, landscape painting, 

 and the arrano^ement and cultivation of exotic veffetabJe 

 forms), of the history of the contemplation of the universe, or 

 the gradual development of the reciprocal action of natural 

 forces constituting one nat.Jiral whole ; and, lastly, of the spe 



