1698, the pendulum began to swing in the other direction. As a result, investment lagged while Lisbon devoted itself to the more lucrative trade with India and the Far East and to the colonisation of Brazil. During the 18th and 19th centuries, the Mazrui and Omani Arabs reclaimed much of the Indian Ocean trade, forcing the Portuguese to retreat south. Many had declined by the mid-19th century, but several of them survived. During the 19th century, other European powers, particularly the British and the French, became increasingly involved in the trade and politics of the region. In the Island of Mozambique, the hospital, a majestic neo-classical building constructed in 1877 by the Portuguese, with a garden decorated with ponds and fountains, was for many years the biggest hospital south of the Sahara. By the early 20th century the Portuguese had shifted the administration of much of Mozambique to private chartered companies, including the Mozambique Company, the Zambezia Company and the Niassa Company, which established several railroad lines to neighbouring countries. The companies, granted a charter by the Portuguese government to foster economic development and maintain Portuguese control in the territory's provinces, would lose their purpose when the territory was transferred to the control of the Portuguese colonial government between 1929 and 1942. Although slavery had been legally abolished in Mozambique by the Portuguese colonial authorities, at the end of the 19th century the Chartered companies enacted a forced labour policy and supplied cheap – often forced – African labour to the mines and plantations of other European colonies in Africa. The Zambezia Company, the most profitable chartered company, took over a number of smaller holdings and requested Portuguese military outposts to protect its property. The chartered companies and the Portuguese administration built roads and ports to bring their goods to market including a railway linking Southern Rhodesia with the Mozambican port of Beira. However, the development's administration gradually started to pass directly from the trading companies to the Portuguese government itself. Because of their unsatisfactory performance and because of the shift, under the regime of Oliveira Salazar, towards a stronger Portuguese control of the Portuguese Empire's economy, the companies' concessions were not renewed when they ran out. This was what happened in 1942 with the Mozambique Company, which, however, continued to operate in the agricultural and commercial sectors as a corporation, and had already happened in 1929 with the termination