Originally Bombay was a city of several islands which were joined into one land mass over a period of time. The first project began in 1784, when the Governor of Bombay, William Hornby, approved the building of the great sea wall. It was done to prevent flooding of the low-lying areas of Bombay. In the mid-nineteenth century, several plans were formulated for reclamation of more land from the sea. Both private and Government companies took part in it. In 1864, the Black Bay Reclamation Company won the right to reclaim the western shore from the tip of Malabar Hill to the end of Colaba. This meant levelling of hills around Bombay. By the 1870s, though most private companies had closed down because of the high cost of reclamation, Bombay had expanded to about 22 square miles. As the population continued to increase rapidly, more and more area was reclaimed from the sea.