Thanks for posting these pictures Fred. I note that the display includes some US infantry items. Many people forget the role of the infantry on the frontier, being influenced by Hollywood which concentrates on the US Cavalry (especially the 7th!). In fact there were only 10 regiments of cavalry for much of the late Nineteenth Century, between the end of the Civil War and the start of the Twentieth Century, of which two, 9th and 10th were raised from African Americans (they were both crack regiments, perhaps the best in the army, but also got all the worst postings, for example it was the 9th that fought Geronimo and the Apaches).The slack had to be taken up by the infantry, endlessly plodding the Plains.
As in the UK, the US Army was a last resort for the desperate during this period, and post Civil War was much neglected. Financial savings were usually at its expense, and at times the establishment of a US Cavalry troop could fall as low as 40 privates. Civil War equipment and uniforms were used all through the 70's and into the 80's. Hence the loss of half of the 7th Cavalry at Little Big Horn was a major disaster.