62 PRACTICAL EXERCISES IX GEOGRAPHY 



distinct air strata within very narrow vertical limits : a lower cold 

 one extending upward al)out 1,500 feet; a warmer one extending to 

 between 2,5.0 and 8,000 feet, and then a second cold one of unknown 

 extent. 



The entire subject of aerial investigation offers a very attractive 

 field to the student. The work has just begun, and future investiga- 

 tors must certainly bring to light many truths, now concealed, which 

 will prove of the utmost interest and value to themselves, the cause 

 of science, and the world at large. 



PRACTICAL EXERCISES IN GEOGRAPHY 



]{y \V. M. Davis, 

 Professor of Physical Geography in Harvard University 



The graduate of a high-school course in physical geography cannot 

 be expected to have reached the stage of indejjendentand original in- 

 vestigation in new fields unless he possesses unusual mental capacity> 

 but he ought certainly to be al)le to recognize the outdoor occurrence 

 of things similar to those that he has studied in school. This would 

 be dillicult if he had studied only a book, even if its text gave good 

 pn'sentation of names, definitions, descriptions, and explanations, 

 supplemented by pictures and maps. It is probably for this reason 

 that we find today an essential unanimity regarding the addition of 

 practical exercises in some form to the lessons in ])hysical geography 

 l)ased on a text. The reports made by the several committees of the 

 National lulucational Association — the Committee of Ten (1893), 

 Committee of Fifteen (189-), and the Committee on College Entrance 

 Requirements (1899) — all emphasize the importance of observational 

 exercises in field and laboratory ; and many progressive schools in 

 which courses of high-school grade in physical geography are given 

 today are doing their best to solve the difficult problems that arise 

 when the attemi)t is made to put these recommendations into prac- 

 tice. 



AUilude of Teachers. — The advantages that come from well-planned 

 field and laboratory' exercises in ph3'sical geograph}'^ are so great that 

 the ditHculties in their way must be overcome in one way or another. 

 Fortunately there is today no more effective aid toward this end 

 than the desire of the teachers themselves to gain it. This is mani- 



