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successive ridges two or three and in instances four. In still other places 
the topography takes the form of dunes, low domes with no characteristic 
order or grouping. The gradients of the ridges on the leeward or east side 
if often remarkably steep. The height of the ridges is in a few cases as much 
as twenty-five feet. In most instances the height is not more than half the 
figure stated. An interesting observation is that the dunes and ridges extend 
along the north sides of tributary valleys still keeping a north-south direction 
in the ridges, which in some places are arranged in etchelon. This is noticed 
on the north side of Honey creek. The surface on the north side of Otter 
creek valley appears as one long wave after another, cloaking the bluff front 
Blake Hill. A sand dune north side National Road. 
and crest. This arrangement of ridges along the re-entrant valleys indicates 
that the valleys were made before the deposits. The direction of the bluffs 
has evidently influenced the deposition of the material as a section of the 
river bluffs running directly east-west on the south side of Honey creek shows 
no dunes or ridges. The deposits also show a marked relation to the terrace 
area in the valley. Where a broad stretch of terrace lies below the bluffs 
the ridges and dunes are more strongly developed. Where flood plains 
approach the bluffs the deposits on the crest and bordering uplands decrease 
or disappear. Conclusions as to the cause of the deposits and their source 
seems to be amply justified by the evidence that the deposits are wind 
