This state of affairs continued until 1800 when Denmark became involved in a war with Great Britain and the islands were blockaded. They endured for a while and surrendered in 1801. After holding them ten months, the British restored them in 1802. The short occupation, however, materially affected the commerce of the island and as a result of further complication in the Napoleonic wars they were conquered again by the English and held from 1807 to 1815. Then came another revival of commerce in these islands, the port of St. Thomas becoming the principal rendezvous for the Royal Mail Steam Packet Company's vessels.[378] Yet to a student of economic conditions it was evident that the prosperity of the colony could not become permanent after the rise of the beet sugar industry at the expense of the cane sugar of the West Indies.[379] During these years slavery was becoming onerous and undesirable in certain parts of the West Indies and humanitarian forces were operating, at least, to ameliorate the condition of the slaves as a preparation for gradual emancipation. Steps were, therefore, taken to do the same in the Danish West Indies but seemingly without permanent results. There still remained evidences of oppression and cruelty and as an observer saw the situation the low physical, intellectual, and moral condition of the slaves, as compared with that of the liberated Negroes of the British islands, was obvious and unquestionable.[380] Some time in the forties, however, a commission was appointed at Copenhagen to inquire into the state of the islands with a view to emancipation. Moreover, there were constructed "seven large buildings in different parts of the island to serve as chapels and schools for the religious and literary instruction of the Negro population." Some of the planters too were making "laudable exertions for the education of their slaves in reading and in a knowledge of the Holy Scriptures."[381] At the head of this system of schools was one McFarlane, an intelligent and efficient man of color, who was successfully disseminating information from plantation to plantation.[382] The condition of the Negroes was thereby improved, but this increasing knowledge instead of making them grateful to their benefactors led them to appreciate freedom and to realize their power.