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A comprehensive guide to one of America's unique national parks, The C&O Canal Companion takes readers on a mile-by-mile tour of the 184-mile Potomac River waterway and towpath that stretches from Washington, D.C., to Cumberland, Maryland, and the Allegheny Mountains. Making extensive use of records at the National Archives and the Park headquarters, the author demonstrates how events and places along the canal relate to the history of the nation, from Civil War battles and river crossings to the frontier forts guarding the route to the West. With photographs and drawings, he introduces park visitors to the hidden history along the canal and provides practical advice on cycling, paddling and hiking -- all the information needed to enjoy fully the park's varied delights. The new edition of this popular book features updated maps and the latest information on lodgings and other facilities for hikers, bikers, and campers. For a weekend excursion or an extended outdoor vacation, this guide remains indispensable for visitors to the C&O Canal park.

Praise for The C&O Canal Companion:

"An informative and affectionate guide to the canal written by C&O devotee Mike High... And yes, it'll fit comfortably in your backpack." -- Mid-Atlantic Country

"High gives practical information about exploring the canal and provides extensive historical background... Provides many opportunities for using the canal as a means of exploring this region's history." -- Historic Traveler

"There are other guides to the canal, but High's is the latest and may be the best. It's a mile-by-mile guide, well-illustrated, full of history and surrounding cultural notes. The more one learns about the canal, the more intriguing it is."--Fredricksburg Free Lance-Star

"A contender for the hearts and minds of canal buffs. It shows the results of serious historical research, particularly about the Civil War, and is well-written and organized." -- Washington Times

from the introductory:

The material upon which this work was done is the same as that used for the preceding researches. It was collected by the author in central Florida and southern Georgia by means of a grant from the Smithsonian Institution, for which assistance acknowledgment is herewith gratefully made.

Various methods of fixation were employed in preserving the material. In practically all cases the embryos were stained in toto with Borax Carmine and on the slide with Lyon's Blue. Transverse, sagittal, and horizontal sections were cut, their thickness varying from five to thirty microns, depending upon the size of the embryos.

The first indication of the formation of the enteron is seen in the very early embryo shown, from the dorsal aspect, in figure 1. The medullary folds and notochord are evident at this stage, but no mesoblastic somites are to be seen.

A sagittal section of approximately this stage, shown in figure 1A, represents the foregut, fg, as a shallow enclosure of the anterior region of the entoderm, while the wide blastopore, blp, connects the region of the hindgut with the exterior. No sign of a tail fold being present, there is, of course, no real hindgut. The entoderm, which has the appearance of being thickened because of the fact that the notochord has not yet completely separated from it, is continuous, through the blastopore, with the ectoderm. Posterior to the blastopore 2 the primitive streak, ps, is seen as a collection of scattered cells between the ectoderm and the entoderm, apparently formed by proliferation from the ventral side of the ectoderm.

A slightly later stage is shown in figure 2, a dorsal view of an embryo with five pairs of mesoblastic somites. A sagittal section of this stage is shown in figure 2A. The foregut is here more inclosed, and the notochord, nt, having separated from the entoderm, en, is seen as a distinct layer of cells extending from the foregut to the blastopore.

A transverse section through the headfold of this stage is shown in figure 2B. The foregut is seen as a wide cavity, ent, depressed dorsally, apparently, by the formation of the medullary groove and the notochord; it is wider laterally than in a dorso-ventral direction, and its walls are made up of about three layers of closely arranged, irregular cells; the wall is somewhat thinner on the dorsal side, just below the notochord.

Figure 3 is a dorsal view of the next stage to be described; about fifteen pairs of somites are present.

Figure 3A is a transverse section through this embryo near the anterior end of the enteron, ent, which cavity, cephalad to this region, is bluntly pointed. As seen in the figure the enteron is here wide from side to side, and is depressed dorso-ventrally except for a wide groove in the ventral wall. This groove is lined with rather more closely arranged cells, and marks the region where the mouth will break through at a somewhat later stage. A short distance caudad to this region the groove disappears and the pharynx is reduced to a shallow slit extending almost to the superficial ectoderm on either side; then the slit-like pharynx becomes suddenly reduced in a lateral and increased in a dorso-ventral direction, to assume the outline shown in figures 3B and 3C. At a point about one-third of the length of the embryo from the tip of the head, the enteron opens to the yolk-sac, so that what now may be called the foregut has this considerable extent. There is, however, not the slightest indication of a tail-fold, so that there is no inclosed hindgut at all. As is shown in figure 3D, the neurenteric canal, nc, still opens ventrally, though the medullary canal, mc, has now no dorsal opening to the exterior.

A 50-mile shortcut to the Pacific lying just north of the equator is one of the most extraordinary human achievements ever. The building of the Panama Canal was a massive feat of engineering and ingenuity that cost millions of dollars and thousands of lives. NOVA offers a unique opportunity to explore the mind-boggling undertaking through historic film footage, rare archival photographs and insightful narration from author David McCullough.

Get an unprecedented look at the Canal's dangerous 30-year construction and wondrous present-day operation. Meet the persevering pioneers whose vision and determination overcame tremendous physical—and fiscal—obstacles. Understand why France abandoned the project after ten years and 20,000 deaths. Work alongside the builders who turned a fantastic dream into a fascinating reality. See immense steamshovels carve the earth. View the amazing "water elevators" that lift huge vessels 85 feet. Watch high-speed photography capture a lock passage. And much more!

On one DVD5 disc. Region coding: All regions. Audio: Dolby stereo. Screen format: 4 x 3 full frame.