CHAPTER XVII, 113 



composed of coarse, rough bread, onions or garlic, and olives or olive 

 oil. In Italy the southern laborers, I noticed, eat the black olive, such 

 as we pickle here. The brine furnished them with salt. In Southern 

 Spain there Is the same square-set, heavy race, neither blonde nor 

 brunette, that is found in the interior of Sicily. These people I have 

 only seen casually loading or handling freight along the South coast of 

 Spain, but then noted their use of olive oil on coarse bread. Olive oil 

 is rather expensive and is an article of common use amongst but 

 few of those likely to be in the forestry service. We could not, there- 

 fore, make it a part of the general ration. What we can do, however, 

 is to introduce it and try the men on that form of fat, as compared 

 to other forms. It is of special importance to find the best form of 

 fat for human use in a climate as mild as ours is and to be consumed 

 during the warmest season. Fats not only furnish body heat, but also 

 nerve energy. In a warm or mild climate, that form of fat should be 

 sought that goes most to energy and least to heat, except as a mani- 

 festation of such energy. In the tropics there are no strong civiliza- 

 tions. None have ever originated there. Even those primitive forms 

 of society found in Mexico and Peru were on the high plateaux, and 

 consequently in comparatively temperate climates. It is to be pre- 

 sumed that man originated in the tropics. This makes the absence of 

 noted human advance in the moist warmth of these regions a subject 

 of interest. Two reasons for this are theoretically presentable. 



First — Civilization is the result of human energy. Energy is only 

 possible by the development of heat. Heat in the tropics is already 

 and constantly near that of the living, human body. Human energy 

 in the tropics produces heat that requires other energy to get rid of. 

 The greater the heat and moisture of the air combined, the greater be- 

 comes the difficulty of getting rid of surplus body heat produced by 

 energy. The exercise and energy which we seek in the temperate zone 

 is in part sought because we feel better physically because of it. In 

 the moist tropics, exercise of body or mind is irksome and evaded be- 

 cause we suiler with the heat our own action creates. A dry-warm 

 air enables the rapid evaporation of moisture from the body to easily 

 neutralize the surplus heat. In very cold climates or very high alti- 

 tudes, the energy required to neutralize the cold, prevents the human 

 being from using energy for development. As there is no civilization 

 that has come out of the tropics, so there is none that has come out 

 of the Arctic Circle. The climate of Southern Colifornia is the type 

 out of which all the great civilizations of the past have come. Doubt- 



