of the Mediterrcmean. ^47 



tarrhs ; and to elicit those affections, it seems necessary that the 

 warm and moist winds should be preceded by cold ones ; — having 

 some analogy to the circumstance of individuals catching cold, 

 or a catarrh, not from being exposed to cold alone, but from 

 coming into a warm room immediately after exposure to the 

 cold air. 



Humidity. — The hygrometrical condition of the atmosphere 

 is an important object of attention in any climate, and it exerts 

 a great modifying influence in that of the Mediterranean. This 

 state of the air is very much affected by the direction of the 

 winds, as well as by the temperature at the time ; it also nearly 

 observes variations corresponding with the temperature, being 

 generally, in its sensible qualities, drier as the air is warmer, and 

 moister as it is cooler. An exception to this concomitancy, how- 

 ever, exists in the currents of air over an extent of sea being al- 

 ways moist, whether in summer or winter ; though, it must also 

 be added, that the Sirocco, if felt moist at first on the northern 

 shores of the Mediterranean, becomes drier if it continues for 

 some days ; and it sometimes will arrive there in all that arid 

 state which is experienced on the coasts of Barbary and Egypt. 

 Winds off land free from marshes, are dry in summer ; and 

 they are steadily moist, if they blow from snowy surfaces in the 

 advanced part of the cold season. They are therefore moist, 

 from moist places, in winter, under many changes of the wind ; 

 for the temperature never descends so low as to reduce the eva- 

 poration to a nullity, but ranges between those degrees on the 

 scale where the dew point is very near the point of saturation. 



At Modon, in the south of the Morea, the humidity in sum- 

 mer is much influenced by the prevailing winds. After the 

 snow has melted on Pindus, Olympus, and Mount Taygetus, 

 the land winds are dry, and the south winds are moist. If these 

 last have blown for a length of time, they become drier, espe- 

 cially if they are of the Sirocco, and even if they have blown 

 over the sea long in any direction ; for it appears the longer 

 winds blow over the sea, if it does not get agitated, the evapora- 

 tion becomes less, and it is much greater after rains or heavy 

 dews, which seem to form a thin stratum of fresh water on the 

 surface, liable to be instantly evaporated on the first increase of 



