12 OUR HERITAGE THE SEA 



over the ocean's wide surface the sun is daily engaged 

 in raising from the bitter brine of the sea an incal- 

 culable supply of sweet fresh water, which those swift 

 messengers the winds are everlastingly hurrying with 

 to the dry land. This raising of fresh water from the 

 sea is accomplished in two ways, by evaporation and 

 by the mysterious and marvellous phenomena known 

 as waterspouts. The first process is familiar to us all, 

 the way in which a vessel of water in a dry room will 

 gradually diminish in quantity, the dry air like a 

 sponge sucking up the water and holding it in in- 

 finitesmal particles, ready to let them fall upon a 

 sudden alteration of atmospheric conditions. We all 

 are familiar, too, with the phenomenon of what we call 

 a damp day, when the air is like a vapour bath, and 

 everything around becomes clammy and moist. There 

 may be no clouds laden with rain, yet everything is 

 wet, and we cannot help feeling that the whole atmo- 

 sphere is almost as dense as water itself, and only 

 needs some slight change to let it fall in heavy rain. 

 In the terms of the meteorologist, the air is at satura- 

 tion point. 



But steady and universal as is this system of 

 evaporation, and essential as it is to our well-being, 

 it must needs be supplemented by the raising of 

 enormous quantities of water almost in bulk, and load- 

 ing with this prime necessity whole squadrons of aerial 

 water-bearers, to be propelled by the winds to where 

 they are most needed. Here we are at once upon debat- 

 able ground, where scientists disagree most furiously. 

 As, however, we are not scientists, but only concerned 

 with facts which interest us, and just incidentally with 

 their causes, we need not be alarmed. What is certain 



