Some Pro-Glacial Lake Shorelines 
243 
stone island, commencing in section 14 of York Tp., the beach 
ridge proper of the Whittlesey level is again found; a school 
house on the north side of the highway stands near the begin- 
ning of this beach. For nearly three miles directly northeast, 
a ridge of sandy clay marks the work of Whittlesey waves ; thence 
the shoreline turns to the northwest, and becomes quite irregular 
because of limestone islands, a condition that makes mapping 
of the shoreline rather problematical. I have indicated some 
isolated patches of what appear to be wave-worked materials, 
extending eastward from a cliff phase of limestone. After cross- 
ing the Sandusky County line again this beach bears southward 
for approximately one mile, thence southwest for nine miles, 
being traversed by a highway continuously to the western border 
of the quadrangle. As indicated on the map, there are several 
segments or ridges varying in length, south of the main ridge, 
which mark earlier, but more temporary positions of the Whit- 
tlesey shoreline. Within about a mile of the Lake Shore Electric 
Railway the ridges become more complex both genetically and 
by later drifting of sand. South of the Lake Shore and Michigan 
Central Railroad an inner ridge has been mapped which is con- 
tinuous, except where cut by streams, to the edge of the sheet. 
Islands. An island northeast of Parkertown is locally known 
as Sand Hill; it was about one mile long, and did not stand very 
far above the Whittlesey level. The limestone of which it is 
composed furnished the waves a supply of material for erosion 
and transportation; cliffs border the northern and northeastern 
sides of the island. Along its west side are beach deposits, the 
finer surface parts of which have been drifted inland by the 
wind; the topographic map appears to indicate several of these 
dunes, the axes of which, however, are erroneously given a north- 
east-southwest trend; their direction is more nearly east-west. 
From the southwestern part of this island a short spit was built 
into the deeper water. About 40 rods east of this, a strongly 
developed spit, composed entirely of limestone gravel which 
becomes finer in texture toward the terminus, extends southward 
for over one-half mile; this spit has a recurved termination which 
is very typical in all its measurements; Fig. 4 gives a longitudinal 
profile and the ground plan of this hook-termination; the direc- 
tion of the curve shows clearly the influence of deeper water 
south of the island, carrying the predominating waves to the 
east. 
