Geogra^liiG Methods in Geologic Investigation. 21 



previous lower stand of the land to its present elevation. There 

 is a parable that illustrates the principle here presented. 



An antiquary enters a studio and finds a sculptor at work on a 

 marble statue. The design is as yet hardly perceptible in tlie 

 rough cut block, from which the chisel strikes off large chips at 

 every blow ; but on looking closer the antiquary discovers that the 

 block itself is an old torso, bi'oken and weather beaten, and at 

 once his imagination runs back through its earlier history. 

 This is not the first time that the marble has lain on a sculptor's 

 table, and suffered the strong blows of the first rough shaping. 

 Long ago it was chipped and cut and polished into shape, and 

 perhaps even set up in its completed form in some garden, but 

 then it was neglected and badly used, thrown over and broken, 

 till its perfect shape was lost, and it was sold for nothing more 

 than a marble block, to be carved over again if the sculptor sees 

 fit. Now it just beginning its second career. We may find 

 many parallels to this story in the land about us, when we study 

 its history through its form. The sequence of events and conse- 

 quently of forms is so apparent here that no one could have 

 difficulty in interpreting history from form, and it shall come to 

 be the same in geography. The gorge of the Wissahickon 

 through the highland northwest of Philadelphia can have no 

 other interpretation than one that likens it to the first quick work 

 of the sculptor on the old torso. 



An essential as well as an advantage in this extension of the 

 study of geography will be the definition of types and terms, 

 both chosen in accordance with a rational and if possible a natural 

 system of classification. Types and terms are both already in- 

 troduced into geographic study, for its very elements present 

 them to the beginner in a simple and rather vague way : moun- 

 tains are high and rough ; lakes are bodies of standing water, 

 and so on. It is to such types and terms as these that every 

 scholar must continually return as he reads accounts of the 

 world, and it is to be regretted that the types are yet so poorly 

 chosen and so imperfectly illustrated, and that the terms are so few 

 and so insufiicient. Physical geography is particularly deficient in 

 these respects, and needs to be greatly modified in the light of the 

 modern advance of topography General accounts of continental 

 homologies of course have their interest and their value, but they 

 are of the kind that would associate whales with fishes and bats 

 with birds. The kind of reform that is needed here may be per- 



