INTRODUCTION. Xlii 



the cause of any department of physical science as is that which 

 is now about to be engaged in advancing our knowledge of the 

 Physical Geography of the Sea, and never before have men felt 

 such an interest with regard to this knowledge. 



Under the term " Physical Geograph}'- and its Meteorology," 

 will be included a philosophical account of the winds and currents 

 of the sea ; of the circulation of the atmosphere and ocean ; of 

 the temperature and depth of the sea ; of the wonders that lie 

 hidden in its depths ; and of the phenomena that display them- 

 selves at its surface. In short, I shall treat of the economy of 

 the sea and its adaptations — of its salts, its waters, its climates, 

 and its inhabitants, and of whatever there may be of general 

 interest in its commercial uses or industrial pursuits ; — for all 

 such things pertain to this department of science. 



The object of this work, moreover, is to show the present 

 state, and, from time to time, the progress of this new and 

 beautiful system of research, as well as of the advancement made in 

 this interesting department of science ; and the aim of the author 

 is to present the gleanings from this new field in a manner that 

 may be interesting and instructive to all, whether old or young, 

 ashore or afloat, who desire a closer look into " the wonders of 

 the great deep," or a better knowledge as to its winds, its 

 adaptations, or its Phj'sical Geograiohy.* 



* There is an old and very rare book which treats upon some of the subjects 

 to which this little work relates. It is by Count L. F. Maksigli, an Italian, 

 and is called NATrRAL Description of the Seas. The copy to which I refer 

 was translated into Dutch by Boerhaave in 1786. 



The learned count made his observations along the coast of Provence and 

 Languedoc. The description only relates to that part of the Mediterranean. 

 The book is divided into four chapters : the first, on the bottom and shape of 

 the sea ; the second, of sea water ; the third, on the movements of sea water ; 

 and the fourth, of sea plants. 



He divides sea water into surface and deep-sea water ; because, when he 

 makes salt from surface water (not more than half a foot below the upper 

 strata), this salt will give a red colour to blue paper ; whereas the salt from 

 deep-sea water will not alter the colours at all. The blue paper can only 

 change its colour by the action of an acid. Tlie reason why this acid (iodine ?) 

 is found in surface and not in deep-sea water is, it is derived from the air ; but 

 he supposes that the saltpetre that is found in sea water, by the action of the 

 sun's rays and the motion of the waves, is deprived of its coarse parts, and, by 

 evaporation, embodied in the air, to be conveyed to beasts or plants for their 

 existence, or deposited upon the earth's crust, as it occurs on the jJlfiins of 

 Hungary, where the earth absorbs so much of this salti^etre vapour. 



Donati, also, was a valuable labourer in this field. His inquii-ies enabled 



