hurricane of 1872, on Pemba Island. In the last decades of the century, sugar and grain plantations took root on the coast itself, creating further demand for labour (Cooper, 1977; Glassman, 1995). In Arabia the growing market for pearls in Europe and North America stimulated the demand for labour in the pearl beds of the Gulf (Hopper, 2015). Meanwhile, a steady market for both male and female domestic labour continued in Oman, even after the State was separated from Zanzibar following the death of Seyyid Said bin Sultan in 1856. In the insular southwest Indian Ocean, the abolition of slavery by Great Britain in 1834 and by France in 1848 made it more difficult to meet labour demands on the rapidly expanding sugar plantations of colonial Mauritius, Reunion Island, Nosy Be and Mayotte. The British resolved this problem by instituting a system of indentured labour from India, whereas the French resorted to a system of so-called 'free labour emigration' from East Africa that amounted to a form of thinly disguised slave trade. There was also an increased demand for agricultural slave labour in western Madagascar in the nineteenth century that did not cease until abolition in 1896 (Campbell, 2005).