A Smithsonian trinomial (formally the Smithsonian Institution Trinomial System , abbreviated SITS ) is a unique identifier assigned to archaeological sites in many states in the United States . Trinomials are composed of a one or two digit coding for the state, typically two letters coding for the county or county-equivalent within the state, and one or more sequential digits representing the order in which the site was listed in that county. The Smithsonian Institution developed the site number system in the 1930s and 1940s, but it no longer maintains the system. Trinomials are now assigned by the individual states. The 48 states then in the union were assigned numbers in alphabetical order. Alaska was assigned number 49 and Hawaii was assigned number 50, after those states were admitted to the union. There is no Smithsonian trinomial number assigned for the District of Columbia or any United States territory.
7-615: The Swallow Bluff Island Mounds ( 40HR16 ) comprise a Mississippian culture archaeological site located near Saltillo on Swallow Bluff Island in the Tennessee River in Hardin County, Tennessee . The Swallow Bluff Island Mounds site is the northernmost outpost of the Mississippian culture Shiloh polity, a group of communities centered on the much larger Shiloh or [Savannah Mound sites . The site featured two platform mounds ,
14-423: A plaza , and a village area. When Clarence Bloomfield Moore visited the site in 1914, he recorded the larger mounds' dimensions as a square 130-foot (40 m) base, with a50-foot (15 m)-diameter top platform area, and as being 18 ft (5.5 m) in height. Excavations in 2003 revealed the mound had been built up in four different construction stages. Moore also described the mounds as being very close to
21-538: A sequential number series for the whole state. Delaware uses a single letter code for counties and adds a block code (A-K) within each county, with sequential numbers for each block. Hawaii uses a four-part identifier, "50" for the state, a two-digit code for the island, then a two-digit code to designate the USGS topographical quad, plus a four digit sequential site number for sites on each island. NN: One or two digit number, 1 though 16, identifying rectangles (15 ' USGS maps) in
28-422: The county code. Arizona uses a five-part identifier based on USGS maps, specifying quadrangles, then rectangles within a quadrangle, a sequential number within the rectangle, and a code identifying the agency issuing the sequential number. California uses a three-letter abbreviation for counties. Connecticut and Rhode Island do not use any sub-state codes, with site identifiers consisting of the state abbreviation and
35-425: The early 1980s, archaeologist Gerald Smith visited the site to investigate suspected pot looters holes, although they may actually been the remnants of Moore's "excavations". After a disastrous flood in 2003, archaeological surveys and excavations were undertaken to learn as much about the main mound as possible before it was completely claimed by the river. Smithsonian trinomial Most states use trinomials of
42-455: The form "nnAAnnnn", but some specify a space or dash between parts of the identifier, i.e., "nn AA nnnn" or "nn-AA-nnnn". Some states use variations of the trinomial system. Arizona, California, Connecticut, Maine, Rhode Island, and Vermont use two-letter abbreviations of the state name instead of the Smithsonian number. Alaska uses three-letter abbreviations for USGS map quadrangles in place of
49-459: The river, although he did not record how close. By the late 20th century, the river had encroached onto the mound, and by the early 2000s, a significant amount of it had been eroded away. In his 1914 visit, C. B. Moore dug into the main mound looking for pottery and other artifacts. He found over 20 stone box graves at the summit of the mound. After his visit, the site went without notice again, except by locals and looters, for almost 70 years. In
#544455