ofilie Mediterranean. ftSl 



Of the grand phenomena of this subtle yet mighty agent, the 

 Mediterranean exhibits every year many conspicuous examples ; 

 and especially when the summer constitution of the weather 

 breaks up for the season. During the winter and spring months, 

 thunder and lightning do not often occur ; but I have never 

 observed the season to change during the decrement of tempera- 

 ture, without more or less of electrical phenomena taking place, 

 and often to a frequent and great extent. In the months of 

 August and September, when the temperature thus begins to 

 fall, and the winds have blown from the north, and over any ex- 

 tent of sea, for some days, the atmosphere will become often ob- 

 scured mth irregularly formed clouds to leeward, — the wind 

 will next change or abate, and, during the evening and night, 

 successive evolutions of electricity will be seen on the upper 

 part of the newly deposited clouds, which are precipitated, one 

 after another, from the muddy and misty atmosphere above. 

 Rain next succeeds without'^iT/under ; and in twenty-four hours 

 the wind will again change steadily to the northward, ,with a 

 clear sky, fine weather, and a permanent fall of the thermome- 

 ter. If tliese phenomena are witnessed on the coasts of Italy 

 and Greece, the deposition of clouds takes place over the high 

 lands ; and the electrical transitions are accompanied with thun- 

 der and forked hghtning,- — often exhibiting the sublimest in- 

 stances of elemental commotion. 



I always remarked the developement of electric light to be 

 from the upper outline of the newly precipitated strata of clouds; 

 and where these fresh charges of electric light were successively 

 transmitted from cloud to vapour, they, no doubt, were accom- 

 panied with much evolution of caloric, from the vapour parting 

 with its latent or constituent heat. The direct preliminary con- 

 dition of such phenomena seemed to be a wind from the sea, or 

 from the south. Such winds as the Sirocco are always attended 

 with imperfectly formed clouds, or a hazy atmosphere ; and, on 

 the converse, I have often seen a change of wind to the south and 

 east from the northward, completely dissolve the regular clouds, 

 and render the air muddy and hazy. These remarkable elec- 

 tric phenomena will more particularly happen, if these south- 

 cast or south winds have blown for some time, and have been 

 immediately preceded by northerly winds, or winds off the 



