THE ATMOSPHERE AND ITS CURRENTS. 



445 



direction of the atmo- 

 spheric currents along the 

 shore, its long tail stretch- 

 ing landwards for a few 

 hours, and then veering 



round to seaward. In the Mediterranean and the West 

 Indies, the land breeze usually begins at six or seven o'clock 

 in the evening, and blows until eight in the morning, 

 when the sea breeze begins, increasing till mid-day, and 

 gradually dying away in the afternoon, a period of stillness 

 occurring between the changes, as between the ebbing and 

 flowing of the tide. The sea-breeze of the Mediterranean 

 in summer is said to be perceptible sometimes as far north 



as Norway. These draughts of the cool air of the ocean are important benefactions to 

 various countries, where the heat would otherwise be insupportable. Along the coast 

 of Malabar, the alternate breezes are powerfully felt, the land wind extending in summer a 

 considerable distance out to sea, redolent with the roses and spices of the shore. Though 

 the land and sea breezes are most sensible in tropical countries, yet in far remote lati- 

 tudes, and especially around lakes, the same diurnal shifting in the direction of the wind 

 is experienced. The change of temperature in the air over a spacious lake, caused by 

 the succession of day and night, has been computed to be about thirty times less than 

 that which takes place in the atmosphere of the surrounding land the air over the 

 land being much more heated during the day, and much less heated during the night, 

 than that over the lake an inequality of temperature' which necessarily occasions a 

 breeze from the lake by day, and towards it by night. 



The old and faithful voyager, Captain Dampier, in a quaint but pleasing style, has 

 given the most exact description of these remarkable winds, as they occur in tropical 

 latitudes. " These sea-breezes do commonly rise in the morning about nine o'clock, 

 sometimes sooner, sometimes later ; they first approach the shore so gently, as if they 

 were afraid to come near it, and ofttimes they' make some faint breathings, and, as if not 

 willing to offend, they make a halt, and seem ready to retire. I have waited many a 

 time, both ashore to receive the pleasure, and at sea to take the benefit of it. It comes 

 in a fine small black curl upon the water, whereas all the sea between it and the shore, 



