102 POPULAR SCIENCE MONTHLY. 



tions are found, in desert countries: mountain and plateau by tlie 

 side of tlie plain; regions of primary rocks by the side of limestone 

 formations, clays, sands, and lands of wbolly different composition 

 and age; hot and dry climates, and moist and cool; the sharp prom- 

 ontory looking out upon the open, and the gulf with low and swampy 

 coast; and yet, also, among the countries that attract man, we can 

 cite side by side the plain fruitful in harvest and the mountain rich 

 in minerals; the temperate climates of the European seacoast and 

 the hot and moist climate of the Soudan. The value of a country, 

 therefore, does not depend upon any form of relief or any special 

 situation or particular nature of the ground, or special climate, but 

 upon all these things together and the way they are combined. Soil 

 and climate affect fitness for agi-iculture ; the geological formation 

 bears on mining industry; relief, climate, and geological structure 

 regulate the natural motor powers ; and all these together, with situa- 

 tion, determine fitness for commercial enterprises. We may, there- 

 fore, define a country as the j^roduct of these four factors, either 

 of which may, now here, now there, have the greater part in deter- 

 mining its production. If three of the factors are common to two 

 countries, it only needs for the fourth to be different to determine a 

 variance. Let one of these factors be eliminated, and the product 

 becomes nothing. Such is the case in Greenland and desert coun- 

 tries generally, where the climate, a relativly minor factor as to 

 human existence in itself, produces a condition, however favorable 

 the other factors may be, that makes human life almost impossible. 



Thus in these four initial factors and their infinite combinations, 

 under which the most numerous aspects and various conditions are 

 engendered, are to be sought the reasons for the contrasts which are 

 presented in the various regions of the earth and the human com- 

 munities that are developed in them. 



Both the earth and man are changing all the time, but there is 

 no correspondence in the rate or the nature of the changes they un- 

 dergo. The earth changes very slowly — so slowly that the progress 

 is hardly appreciable in the lifetime of a single man, or so far, almost, 

 of the human race; yet the continuance of its changes through a 

 time of incalculable duration has made them very important, and 

 has exposed it to many great revolutions. 



Man undergoes vastly more rapid transformations. He is one of 

 the latest comers on the earth, and has had an existence relatively as 

 of only a moment. Yet he has undergone most wonderful transfor- 

 mations in his development from the cave dwellers of the stone age 

 to the highly civilized man of the present, with his extensive knowl- 

 edge and complicated relations. It is no exaggeration to say that the 

 distance from the primitive man to the contemporary Englishman or 



