234 
THE SEINE, THE MEUSE, AND THE MOSELLE 
old valley floor near the elbow of capture, just south of the vil- 
lage of Chanipigueules. Here all the different parts are easily 
recognized, as if on a model made expressly for the explanation 
of the problem. In some pits dug here and there by the road- 
side on the plain one may see the old river gravels laid down by 
the Aire while it was running at this high level on its way north- 
ward to the INIeuse. Another point of view no less instructive is 
offered after surmounting the hill by which the national road 
soutliward from Sedan, on the Meuse, crosses over to the valley of 
the Bar at Chevenges. Fi*om the summit and along the south- 
ward descent one has a beautiful view of the broad valley as it 
swings around the narrow-necked sjiur of the Bois la Queue, but 
he looks in vain for the stream by which the valley was cut. He 
fails to see any stream at all until descending to the valle}^ floor, 
when the only occupant of the great, boldly swinging valle}^ is 
found to be a little meadow brook. 
Here, as before, it should be remembered that it is not the 
width of the valley that is essentially discordant with the size 
of the brook that now drains it; for in the late maturity of the 
geogra))hical development of a land surface even small streams 
have broad valleys. Tlie discordance which proclaims that the 
valley is not the work of the existing stream is seen in the rela- 
tive dimensions of their meanders. The valley swings regularly 
in curves of at least half a mile in radius, and maintains this habit 
of curvature with small diminution far up toward the elbow of 
capture and probably still further south. The stream turns and 
twists in curves whose radius may often be less than a hundred 
feet. * 
In comparing the case of the Toul (upper Moselle) and Aire, 
we see that these rivers are the diverted upper portions of 
♦ The following altituiles are instructive: 
Junction of Bar and Meuse 153 m. 
Divide in old valley-trough between the beheaded Bar and the reversed Bri- 
quenay-Agron on the meadows west of Buzancy 175 m. 
Junction of the reversed Briquenay-Agron with the Aire at the elbow of 
capture 130 m. 
Floor of old Aire valley at elbow of capture 182 m. 
Junction of Aire and Aisne 113 m. 
The advantage of depth thus gained by the Aire is about 50 m. 
It is worth noticing that if the Aire had not been diverted at Grand Pr6 it would 
have soon been captured farther down its former valley at Brieulles-sur-Bar for here 
the Fournelle, a branch of the Aisne, has almost cut through the forested ridge of 
Argonne, as the following heights show : 
Mouth of Fournelle in Aisne by Vouziers 100 m. 
Divide between head of Fournelle and Bar near Noirval 174 m. 
Bar at Brieulles 168 m. 
