One event on the timeline was the building of the Fort Peck Dam, along with a photo showing construction. That photo looked familiar: aha, no doubt it had inspired Sheeler's painting "Water", which has a goofy title since it shows no water. So I traipsed through the exhibit, keeping an eye out for "Water"… but it wasn't there. So now I wonder why that Fort Peck Dam item was in the timeline. Had the curators hoped to get "Water"? Or maybe they didn't but left that item in as an "easter egg" for Sheeler fans? If so, it worked: this got me to go through the exhibit a second time to make sure I hadn't accidentally skipped something.