The pre 1900 sections is just that, a section to document and discuss pre 1900 Danish military rifles including the following:

1866 Danish Snider (conversion) 17x28R
1867 Remington Rolling Block M1867 11.7×41.5R
1889 Krag-Jørgensen M1889 8x58RD
1896 Remington Rolling Block M1867/96 11.7×51.6R

Of course the other thing it could be construed as is a tick list, it would be fun to hold and shoot one of each of these models and it is certainly something to aspire to.