With the Grand Canyon plan as its subject, the Museum Branch approached this problem empirically by a deliberate experiment in teamwork. Lewis went to the park in September 1955 to gather data and plot the story line. Two weeks later Buffmire joined him at the park as designer. Together they worked out the exhibit plan in about two weeks of concentrated effort, one proposing content and drafting label copy while the other developed layouts that seemed to communicate the ideas intended. As the plan grew, each reacted constructively to the other's concepts.37 The experience convinced both men that curator/designer exhibit planning teams could increase the efficiency of the process and raise the quality of the product. Execution of the Grand Canyon plan typified park museum practice under the postwar Museum Branch. The museum presented subject matter selected to meet criteria of significance rather than assumed popular interest. The presentation was basically cognitive, on the assumption that public enjoyment of the park must arise largely out of understanding. Affective aspects of the Grand Canyon experience also received considerable attention, although the Service was still groping in the realm of aesthetic interpretation. One exhibit, for example, concerned the changing moods of the canyon and the necessity of taking time to observe them. Paintings and prints by several distinguished artists hung strategically in the exhibit room, illustrating efforts to reduce the vast complexity of the canyon scene into comprehensible scope. Quotations from Henry Van Dyke's poetic tribute to the Grand Canyon provided a connecting thread in the exhibit sequence. The exhibits followed an essentially chronological flow without sharp breaks between such traditional subject matter fields as geology, biology, anthropology, and history. Circulation through the succession was enhanced, but not forced.

The museum retained the interpretive theme of Time-Movement- Change originally proposed for the park by John C. Merriam and aimed to reinforce the still-effective Yavapai Observation Station rather than supersede or compete with it. Specimens provided prime evidence for much of the story. A series of six units represented something of a tour de force in this regard. Three small dioramas pictured widely different local habitats deduced from the geologic record: a sea bottom, a swamp, and a desert, each containing models of prehistoric life forms. What was unusual was that all the models in each group represented species whose fossils had been found close enough together to suggest they had lived in relatively close association. An exhibit case flanking each diorama displayed the fossils and rocks that supported the conclusions depicted.

Technical aspects of the Grand Canyon installation also illustrated Museum Branch practice well. The windowless walls of the exhibit space protected all specimens from direct exposure to sunlight, but visitors could see token daylight from practically every point within the room by looking back toward the lobby or ahead to the patio. An installation crew from the laboratory aided by park staff erected furred walls into which the dusttight, factory-built exhibit cases as well as the dioramas fitted. Case dimensions kept all specimens and labels within optimal viewing range. All exhibit lighting, selected for minimal heat and ultraviolet emission, was external to the cases. One display unit invited visitors to test the hardness of the stone that the eroding river had cut so deeply. Another reproduced the roar of the rapids to emphasize the river's power because many visitors would see the river only from the canyon rim.

The same technical considerations of specimen security and care, convenience and effectiveness of visitor use, durability, and production economy guided the development of the Jamestown and Yorktown museums for Colonial National Historical Park, which were dedicated several weeks before the Grand Canyon museum opened in June 1957. The two Colonial projects developed in an especially stimulating milieu. Both museums had exceptionally good collections on which to base exhibits. Jean (Pinky) Harrington's archeological work in the late 1930s had given Jamestown the fullest representation of 17th-century colonial material culture of any site in the country, and renewed excavations under John Cotter in the mid- 1950s were making important additions to the collection. Yorktown also had extensive artifactual evidence obtained from archeological studies of the field fortifications and other sites, including pioneering underwater archeology among sunken British warships in the York River. Recent acquisitions included such prime specimens as portions of tents General Washington had used at the siege, battle flags surrendered by British and Hessian troops, and a splendid early model of one of the blockading French ships. To supplement many of the excavated fragments at both Jamestown and Yorktown, Harold Peterson succeeded in procuring intact 17th-century examples matching the remnants of arms, armor, tools, utensils, and other articles chosen for display. Superintendent Stanley Abbott's active, innovative mind continually forced those working on the interpretive developments to review their own ideas critically and defend or revise them.

The two museums formed part of a complex, coordinated scheme to mark the 350th anniversary of the first permanent British foothold in North America. The state of Virginia had under simultaneous development the Jamestown Festival Park, just upstream from the entrance to the Jamestown section of the national park. The Festival Park would contain two museums and feature full-scale reconstructions of James Fort, a Powhatan Indian village, and the three ships that had brought the first English settlers. Colonial Williamsburg prepared for the anniversary especially by erecting its new Information Center, containing two theaters of advanced design to show a motion picture intended as the principal interpretive introduction to a Williamsburg visit. This film was costing more than both Park Service museums.