86 THE CRYSTALLINE ROCKS OF CECIL COUNTY 



the strike of the hard rocks and with the cleavage dip, has cut its 

 gorge with some difficulty. Navigation above Port Deposit, except 

 by small craft, is rendered impossible by the innumerable islands, 

 projecting ridges of rock and submerged ledges which interrupt the 

 channel of the river and give rise to frequent rapids. 



It is to this feature that the stream owes its name, which is said to 

 signify in the aboriginal tongue " river of islands." 



Many of these islands were the former secure and picturesque 

 homes of the Susquehannocks — or " Eiver Islanders " and are now 

 a rich collecting ground for aboriginal domestic utensils, stone axes, 

 spearheads and other implements of war. 



The gorge of the Susquehanna in Cecil county is some 400 to 450 

 feet in depth. The first 200 feet rise abruptly and give a consider- 

 able grade to the tributaries. The walls of the gorge approach close 

 to the river bed, except at the entrance of the larger tributary streams, 

 where the deposits of the entering streams have formed low alluvial 

 plains some three-eighths of a mile in width. 



One of the principal towns of the county, Port. Deposit, occupies 

 such a plain, which has been artificially widened. This situation, 

 three miles above the mouth of the Susquehanna, at the head of navi- 

 gation, possessing good waterway and railway connections with Phila- 

 delphia, Baltimore and Harrisburg, has acted most favorably on the 

 chief industry of the town; the quarrying and shipping of building- 

 stone. The high bluffs behind the town offer a picturesque and 

 healthful location for the rapidly developing Jacob Tome Institute. 



The only two tributaries of considerable size, the Conowingo 

 and the Octoraro, have brought their lower courses,, which are con- 

 tained in Cecil county, almost to base-level. The incised meanders of 

 the latter creek indicate that this has been achieved more than once. 

 The carving of these two streams and of the Susquehanna has given 

 a rugged and picturesque character to the northwestern part of Cecil 

 county, which it does not elsewhere possess. Bold bluffs, wooded 

 hills, the flash of winding streams over rocky beds, compose a land- 

 scape which is a constant yet ever varying source of refreshment to 

 the eye. 



