SUN AND CLIMATIC VARIATION 39 



of the sun they create the food which allows them to multiply 

 rapidly. They themselves furnish the inexhaustible provender 

 which attracts the countless infusoria and the minute, almost 

 microscopic, larvae of marine animals of every sort : worms, 

 starfish, sea-urchins, and the small crustaceans which form the 

 interminable army of Copepods — in a word, the whole minute 

 world of life that swarms unceasingly near the surface of waters 

 penetrated by light, and to which the Jena naturalist, Haeckel, 

 gave the name of plankton, including thereby the algse them- 

 selves. The herrings, sardines, and mackerel, in their search for 

 the Copepods they delight in, are themselves pursued by the 

 various tunnies and bonitos ; and these in turn are hunted by 

 porpoises, sharks, and even dolphins. When the weather is 

 clear and the temperature favourable all this teeming life is 

 clearly visible, fishing is fruitful and happiness and prosperity 

 reign among the fishermen. But when the sky is overcast and 

 the winds raise waves and trouble the waters, the debris so 

 fatal to the transparency of the ocean is stirred up, and the 

 plankton at once flees from the sullied surface, descending to 

 calmer zones, attracting in its wake all those creatures that 

 live at its expense. Herring, sardine, and mackerel become 

 rare ; the fisherfolk can no longer gain their livelihood ; and 

 the sound of their lamentations is heard even in Parliament 

 itself. 



All this is the work of the sun. Its activity does not, however, 

 end here. By creating the winds that carry the clouds into the 

 upper regions of the atmosphere, whence they fall in due course 

 in the form of rain, the heat of the sun becomes changed into 

 motion. The water which falls on the high mountain chains 

 and streams down their slopes gradually wears them away ; 

 and this continuous action, however slight it be, produces a 

 prodigious effect. The mountains of 7 or 8 thousand metres in 

 height that formed the Huronian chain, and the younger 

 Caledonian chain, have been completely levelled to the ground by 

 this erosion, which may be said to be also the work of the sun. 

 On the sun, too, depends the energy of watercourses, the energy 

 developed by waves in their assault on the land, and the energy 

 that lies hidden in the depths of the earth in the form of coal, 

 for the sun is the principal builder of vegetable tissues. And as 

 plants, children of the sun, directly or indirectly, are the only 

 source from which animals derive the foods upon which they 



