THE FERNS OF HEMLOCK BLUFF. i^j 



Many of the facts and some of the language in the above account 

 are taken from a notice of Dr. Chapman written by one of his inti- 

 mate friends, Mrs. Clark Kimball, and published in the local paper. 

 The portraits of Dr. Chapman accompanying this article are by the kind- 

 ness of his granddaughter, Miss Wood. The small one on page 141 

 was taken in 1869, while the frontispiece was taken in January, 1896. 



THE FERNS OF HEMLOCK BLUFF. 

 By William Palmer. 



BELOW Washington the Potomac river flows for 100 miles 

 through a tidal estuary of the Coastal Plain region of the Atlan- 

 tic slope. Here the river is wide and crooked, and its banks 

 are either bold Eocene or Miocene bluffs, where the waters 

 are incessantly destroying their bases, or marshes and swamps fringe 

 the historic stream for long stretches. For some 60 miles above 

 Washington, the stream, now narrow and swift, has cut its way 

 through the numerous geological divisions of the Piedmont plateau, 

 tidal level being reached at the Little Falls, three miles above Wash- 

 ington. The country through which this latter portion of the river 

 flows is quite hilly and is cut by numerous "runs" which enter the 

 main stream at right angles to its course. Along the northern bank 

 of the river the summits of the hills are usually at some distance from 

 the river shore, the intervening country presenting gradual slopes 

 toward the river and being dotted with farms and fields. The Chesa- 

 peake and Ohio canal parallels the river on this side at about twenty 

 feet above its level, and a fine driveway, the Conduit Road, winds at 

 a much higher level between the city and the Great Falls, sixteen 

 miles west of Washington. 



The southern bank is quite different, being an almost continuous 

 succession of rocky bluffs which present precipitous and often well 

 wooded steep slopes close to the river side, and usually with their 

 summits fading into the general level of the plateau. The swiftly 

 flowing stream has cut numerous channels in some places and has left 

 many of these hills and bluffs as long, narrow, high and rocky islands, 

 with often a fringe of alluvial mud about their bases or joining one or 

 more together. The most eastern of these is well known to botanists 

 as High Island. Around these Virginia bluffs the action of the river 

 and the elements have left many rocky cliffs and numerous, often 

 enormous, fragments of rock have fallen from above, and in many 

 places dot the surface of the water and fringe the bluffs with almost 

 impassable barriers. Between the bluffs the land slopes inward, 



