WRT to museums, I can tell you from personal experience that things go missing. I volunteer as photo/media archivist and graphics specialist at the Montana Military Museum at Fort William Henry Harrison a couple of miles west of Helena. We are a very small institution with a paid director and all else done by volunteers, most of us Vietnam veterans or spouses/relatives of veterans. I began my tenure there in mid 2011, and in early 2012 our long time curator passed away taking with him mountains of institutional knowledge.
Most of our collection not on display is housed in two small buildings and some Connex storage units. We regularly find things we had no clue were there and sometimes cannot find things we know are there somewhere. We are slowly digitizing our records but it is a slow process and at 64, I’m the youngest person on board and I have chronic health challenges, our eldest docent is a WWII veteran who just passed 93. The museum has been in existence roughly 25 years. We likely have a higher percentage of our collection on display than most museums as our display area is larger than our collections department. Most museums are like ice bergs with the display items the part above water. With most if not all major U.S. museums having been in existence since the 19th century it is not difficult to believe that things slip through the cracks with no conspiracy required. Money wouldn’t make things happen faster unless warm bodies accompanied it, we’re a pretty dedicated bunch but can only do so much.
WRT to the Glacial Lake Missoula Floods and with no disrespect to SWWASASQUATCHPROJECT as they are a special interest of mine, they were more recent than, but every bit as devastating, as he relates. At its maximum, the lake backed up by a glacier blocking the Clark Fork River in present day northern Idaho contained some 500 cubic MILES of water. When the water level approached the top of the glacier dam, estimated at 2000 feet high, pressure forced water into cracks in the ice according to the latest research. The ice dam failed catastrophically and that huge amount of water emptied across Idaho and eastern Washington and down into northwest Oregon over a period of 2 to 3 days. The flow was greater than that of all the current rivers in the world combined. Some of those stones in the Willamette Valley originated in the Canadian Shield, were carried to Montana in glaciers which calved into Lake Missoula, thence carried by the floods to their final resting spots.
Current estimates are that this process repeated at least 36 times during the last ice age, with the latter releases diminished as the glaciers shrank. The time period was likely from about 12k to 9k years BP, and they may have repeated as often as every 30 or 40 years. Anyone who has driven through eastern Washington has seen the evidence of this deluge in the plains and promontories of lava stripped bare of soil. Anyone interested in learning more about this subject would enjoy “Glacial Lake Missoula and Its Humongous Floods†by Geologist David Alt, available here: http://www.amazon.com/s/ref=nb_sb_ss_i_1_26?url=search-alias%3Dstripbooks&field-keywords=glacial+lake+missoula+and+its+humongous+floods&sprefix=glacial+lake+missoula+and+its+humongous+floods%2Cdigital-text%2C215