in 1676, Edmond Halley visited Saint Helena and set up an observatory with a 24-foot-long (7.3 m) aerial telescope with the intention of studying stars from the Southern Hemisphere. The site of this telescope is near Saint Mathew's Church in Hutt's Gate, in the Longwood district. The 680 m high hill there is named for him and is called Halley's Mount.
The importation of slaves was made illegal in 1792. Governor Robert Patton (1802–1807) recommended that the Company import Chinese labour to supplement the rural workforce. The labourers arrived in 1810, and their numbers reached 600 by 1818. Many were allowed to stay, and their descendents became integrated into the population. An 1814 census recorded 3,507 people on the island.
British rule 1815–1821, and Napoleon's exile
In 1815 the British government selected Saint Helena as the place of detention of Napoleon Bonaparte. He was brought to the island in October 1815 and lodged at Longwood, where he died on 5 May 1821. During this period, Saint Helena remained in the East India Company’s possession, but the British government met additional costs arising from guarding Napoleon. The island was strongly garrisoned with British troops, and naval ships circled the island.
The 1817 census recorded 821 white inhabitants, a garrison of 820 men on the East India Company's payroll, 1475 men from the King's troops (infantry, engineers, etc.) + 352 people as their families, 618 Chinese indentured labourers, 24 Lascars, 500 free blacks and 1,540 slaves. In total, 6150 people on the island. In addition, the British Govt had sent a naval squadron under the command of a Rear-Admiral and consisting of a couple of men-in-war and several smaller vessels. These were not counted in the Census, as they lived (for most of them) on their ships. Concerning the slaves, Governor Hudson Lowe initiated their emancipation in 1818: from Christmas of that year, every new born child was
