11 



CHAPTEK II. 



HEAT AND LIGHT. 



The various Sources of Heat Effects of Heat Dependence of Terrestrial Life on 

 the actual Distance of the Earth from the Sun Relations of the various Bodies 

 to Heat The Prismatic Colours The Harmony between Colours and the 

 Human Mind What is Heat? What is Light? Importance of the Ethereal 

 Spaces with regard to the Distribution of Heat and Light. 



SNOW covers the fields, the rivulets are ice-bound, the wintry 

 blast howls through the leafless forest, and at an early hour the 

 languid sun veils his weak rays behind the mists of the western 

 horizon. The songsters of the groves are mute, the insect 

 tribes have disappeared from the face of the earth, and every 

 freeborn animal seeks shelter in burrows or in caves. 



Thus all nature seems to sink into lethargy and death but a 

 wonderful resurrection is at hand. The sun rises higher and 

 higher in the skies, with every returning morn he gilds the 

 purple east sooner and sooner ; every afternoon he disappears 

 later and later to spread his floods of light over another hemi- 

 sphere every day bears witness to an increase of his power. 

 The melting snow descends in a thousand rills from the moun- 

 tains, and the river, overflowing his banks, rushes with all the 

 energy of youthful liberty through the resounding valley. All 

 the dormant germs of organic nature burst forth in an endless 

 variety of forms : the naked forest clothes itself with a fresh 

 robe of verdure, thousands of flowers enamel the fields, thousands 

 of birds sing, and numberless insects buzz or dance in the balmy 

 air, and the wild denizens of the woods wander through the 

 thickets in the full enjoyment of freedom. 



The heat of the sun is the wonderful agent of all these 

 various scenes of activity and happiness ; but the sun is 

 not the only source of heat, which may also be developed in a 

 variety of ways from all terrestrial bodies. Friction heats our 



