13G niYSICAL GEOGKAl'IIY OF THE SEA, AND ITS MKTEOKOLOGT. 



begins to flow in with a most delightful and invigorating fresh- 

 ness. 



315. Cause of land and sea breezes. — AVhcn a five is kindled on 

 the hearth, we may, if we will observe the moats floating in the 

 room, see that those nearest to the chimney are llie first to feel 

 the draught and to obey it — they are drawn into tlie blaze. The 

 circle of inflowing air is gradually enlarged, until it is scarcely 

 perceived in the remote parts of the room. Kow the land is the- 

 hearth, the ra3's of the sun the fire, and the sea, with its cool and 

 calm air, the room ; and thus we have at our firesides the sea 

 breeze in miniature. "When the sun goes down the fire ceases ; 

 then the dry land commences to give off its surplus heat by radi- 

 ation, so that by de^^•-fall it and the air above it are cooled below 

 the sea temperature. The atmosphere on the land thus becomes 

 heavier than on the sea, and, consequently, there is a wind sea- 

 ward Avhich we call the land breeze. 



310. Lieut. Jansen on tlie lamd and sea breezes in the Indian Archi- 

 pelago. — " A long residence in the Indian Archipelago, and, con- 

 sequently, in that part of the world where the investigations of 

 the Observatory at A\'as]iington have not extended, has given 

 me," says Jansen,* in his Appendix to the Ph3-sical Geography 

 of the Sea, " the opportunity of studying the phenomena which 

 there occur in the atmosphere, and to these phenomena my at- 

 tention was, in the first place, directed. I was involuntarily led 

 from one research to another, and it is the I'esult of these investi- 

 gations to which I would modestly give a place at the conclusion 

 of Maury's Physical Geography of the Sea, with the hope that 

 these first-fruits of the log-books of the Netherlands may be 

 speedily followed by more and better. Upon the northern coast 

 of Java, the phenomenon of daily land and sea breezes is finely 



* I have been assisted in my investigations into these phenomena of the sea 

 by many thinking minds ; among those whose debtor I am stands first and 

 foremost the elear liead and warm heart of a foreign officer, Lieutenant INIarin 

 Jansen, of the Dutch Navy, whom I am proud to call niy friend. He has 

 served many years in the East Indies, and lias enriched my humble contribu- 

 tions to the "Physical Geograpliy of the Sea" with contributions from tho 

 store-house of his knowledge, set off and presented in many fine pictures, and 

 has appended thom to a translation of the first edition of this work in the 

 ■ Dutch language. He has added a chapter on the land and sea breezes ; 

 another on the changing of the monsoons in the 1^/ist Indian Archipelago : he 

 has also extended his remarks to the north-west monsoon, to hurricanes, the 

 south-cast trades of the South Atlantic, and to winds and currents generally. 



