MANUAL FOR NONCOMMISSIONED OFFICERS. 317 



A round contour like the letter O outlines a round ground 

 feature ; a long, narrow one indicates a long, narrow ground 

 feature. 



Different hills and depressions have different shapes. A 

 good many of them have one shape at one level and another 

 shape at another level, all of which information will be given 

 you by the contours on the map. 



One of the ways to see how contours show the shape of the 

 ground is to pour half a bucket of water into a small depres- 

 sion in the ground. The water's edge will be exactly level, 

 and if the depression is approximately round the water's edge 

 will also be approximately round. The outline will look 

 something like figure 6. 



Draw roughly on a piece of paper a figure of the same shape 

 and you will have a contour showing the shape of the bit of 

 ground where you poured your water. 



Next, with your heel gouge out on one edge of your little 

 pond a small, round bay. The waiter will rush in and the 

 watermark on the soil will now be shaped something like 

 figure 7. 



Alter your drawing accordingly^ and the new contour will 

 show the new ground shape. 



Again do violence to the face of nature by digging with a 

 stick a narrovr inlet opening out of your miniature ocean, 

 and the watermark will now look something like figure 8. 



Alter your drawing once more and your contour shows 

 again the new ground form. Drop into your main pond a 

 round clod and you will have a new^ watermark, like figure 9, 

 to add to your drawing. This new contour, of the same level 

 with the one showing the limit of the depression, shows on 

 the drawing the round island. 



Drop in a second clod, this time long and narrow, the water- 

 mark will be like figure 10, and the drawing of it, properly 

 placed, will show another island of another shape. Your 

 drawing now will look like figure 11. 



It shows a depression approximately round, off which open 

 a round bay and a long, narrow bay. There is also a round 

 elevation and a long, narrow one; a long, narrovr ridge, jut- 

 ting out between the tw^o bays, and a short, broad one across 

 the neck of the round bay. 



