During the 19th century, the effective, continuous and unchallenged British possession and government for South Georgia was provided for by the British Letters Patent of 1843, revised in 1876, 1892, 1908 and 1917, with the island appearing in the Colonial Office Yearbook since 1887. From 1881 on, Britain regulated the economic activities and conservation by administrative acts such as the Sealing Ordinances of 1881 and 1899. South Georgia was governed by Britain as a Falkland Islands Dependency, a distinct entity administered through the Falkland Islands but not part of them in political or financial respect. These constitutional arrangements stayed in place throughout the second half of the 19th century and most of the 20th century, until South Georgia and the South Sandwich Islands were incorporated as a distinct British overseas territory in 1985.