As a Lieutenant under Commander Thomas Elwon, Moresby was part of a two-ship exercise engaged (from 1829 to 1832) in charting the dangerous waters of the Red Sea.
Robert Moresby's relation to the family is uncertain and it is possible he was the son of another liaison of his father, which might explain his employment in the Bombay Marine, which suffered greatly from being at the bottom of the East India Company's pecking order.
Already before the opening of the Suez Canal, industrial Britain had a rapidly expanding economy and needed improved communication with British India, with its raw materials and imperial requirements.
Surveys of the Red Sea, other than the intimate knowledge of the waters had by Arab pilots, had begun with the Portuguese João de Castro in 1540, with his Roteiro da Mar Roxa.
Knowledge had accumulated in the years since, much of it being cross-correlated by the East India Company's first hydrographer, Alexander Dalrymple, and subsequently by his successor, James Horsburgh.
A year later Elphinstone, together with the secretary of the Calcutta government and his wife, Mr and Mrs Lushington, chose to return to England via the Red Sea, sailing on a cramped little brig, Palinurus.
Back in Britain Elphinstone joined the campaign, promoted by the visionary new commander of the Bombay Marine (renamed the Indian Navy on 1 May 1830), Sir Charles Malcolm, to introduce steam to the Red Sea, which would enable boats to navigate up the Gulf of Suez against those tiresome northerlies.
Drastic measures were clearly needed to prevent these disasters and a rather old ship and a brig were made ready for surveying work despite the reluctance of the East India Company in London to provide finance.
In 1832 Elwon was promoted Captain and rewarded with the dubious privilege of being appointed the Indian Navy's Commodore in the Red Sea, where he died in 1835 aged 41.
[N 2] It is claimed that from 1829 to 1833 Moresby never left the Red Sea, however the survey data indicate that each summer there was a cessation of activity from June to November, when it is probable the ships returned to India for rest and refit.
A fuller and more graphic narrative of the upper half of the survey is contained in Lieutenant James Raymond Wellsted's account, in the second volume of his Travels in Arabia (1838).
Palinurus had been forced to return to Bombay in 1830 for refitting after surveying the Gulf of Suez, while Benares had to be sent back in 1831 in a shattered state, the leaky tub caught forty-two times on coral reefs).
The most curious failing of Moresby's survey was his failure accurately to chart the position of El Akhawein, or The Brothers, an isolate reef in the middle of the northern half of the Red Sea, which he had not seen at all during his first investigations in 1831–32.
The coastal plain had been devastated earlier in the century by Wahhabi puritan Muslims from Central Arabia followed by an Egyptian invasion—none of this good news for non-Muslims.
Meanwhile, the valiant Palinurus sailed on to survey the southern coast of Arabia under Captain Stafford B. Haines, who would later become the first British official in charge of the Protectorate of Aden.
[N 3] After the completion of the Red Sea Survey, Robert Moresby was sent to chart various coral island groups lying across the track of India-to-Cape trade.
This is a vast submerged reef south-east of the Seychelles and since there is no island above the surface, the men were forced to spend many days at sea often under difficult weather conditions.
In 1842 he was employed by the Peninsular and Oriental Steam Navigation Company (P&O), to command their brand new and most luxurious steamer, Hindostan, on her maiden voyage from Southampton to Calcutta.
Subsequently, the Hindostan was employed on the Calcutta-Suez run, the Red Sea now made safe by the immaculate surveys led by Elwon and Moresby.
The beautiful maps of the Red Sea, drafted by the late Commodore Carless, then a lieutenant, will ever remain permanent monuments of Indian Naval Science, and the daring of its officers and men.
Those of the Maldive and Chagos groups, executed by Commander then Acting Lieutenant Felix Jones, were, we hear, of such a high order, that they were deemed worthy of special inspection by the Queen.