PART IV 



EARTH AND SKY 



THE BROOK 



Teacher's Story 



"Little brook, sing a song of a leaf that sailed along, 

 Down the golden braided center of your current swift and strong." 



—J. W. Riley. 



A brook is undoubtedly the most fascinating bit of geography which the 

 child encounters ; and yet how few children who happily play in the brook — • 

 wading, making dams, drawing out the crayfish by his own grip from his 

 lurking place under the log, or watching schools of tiny minnows — ever 

 dream that they are dealing with real geography. The geography lesson on 

 the brook should not be given for the purpose of making work out of play, 

 but to conserve all of the natural interest in the brook, and add to it by 

 revealing other and more interesting facts concerning it. A child who thus 

 studies the brook will master some of the fundamental facts of physical 

 geography, so that ever after he will know and understand all streams, 

 whether they are brooks or rivers. An interesting time to study a brook is 

 after a rain; and May or October give attractive surroundings for the 

 study. However, the work should be continued now and then during the 

 entire year, for each season gives it some new features of interest. 



Each brook has its own history, which can be revealed only to the eyes 

 of those that follow it from its beginning to where it empties its water into 

 a larger stream or pond. At its source the brook usually is a small stream 

 with narrow banks ; not until it receives water from surrounding hills does 

 it gain enough power to cut its bed deeper into the earth, thus making its 

 banks higher. Where it flows with swift current down a hillside, it cuts its 

 bed deeper, because swift-moving water has more power for cutting and 

 carrying away the soil. However, if the hillside happens to be in the 

 woods, the roots of trees or bushes will help to keep the soil from being 

 washed away. Unless there are obstacles, the course of the brook is likely 

 to be more direct in flowing down a hillside than when crossing level fields. 

 The delightful way in which brooks meander crookedly across the level 

 areas is due to the inequalities of the surface, which interfere more with 

 water on a plain than on a hillside, since the gravity which pulls it forever 

 down has less chance to act upon it forcibly in these situations. After a 

 stream has thus started its crooked course, in time of flood the current 

 strikes with more force against the curves, and cutting them deeper, makes 

 the course still more crooked. The places on the banks where the soil is 

 bare and exposed to the force of the current, are the points where the banlcs 

 are cut most deeply at flood time. 



But the brook is not simply an object to look at and admire; it is a very 

 busy worker, its chief labor being that of a digger and carrier. When it is 

 not carrying anything — that is, when its waters are perfectly clear — the 



