unmarried.
From the notes of Oliver de St. Croix:
He twice made and lost a fortune through the treachery of a trusted friend: he then made a third and left £26,800. He went to sea at the age of 13, in the merchant service, and for many years was in command of ships trading with the East. In 1840 he retired with a pension, bought a ship-the John Laird-and in 1842 sailed for China with seven boys on board, the sons of relations and friends, among who was his nephew, George de St Croix. The boys were trained as sailors but 5 of them stayed in China. Nicholas became consular agent at Macao and found jobs for 3 of the boys in business in Hong Kong and Canton. He sold his ship and remained in China until 1851, when he returned to London and spent much time with his great friend, Mr Dent (China merchant), in Fitzroy Square. He was an active committee man of the National Lifeboat Institution and of the training ship Worcester. He is described as "eccentric, liberal, economical to a fault in his own expenses, rarely showing any tenderness, found fault without scruple or cause".
HMS Worcester (from http://www.greenhithe.co.uk/history/history-3.htm): In the middle of the nineteenth century it was felt that there was a shortage of properly trained officers for merchant ships. William Munton Mullivant, a London merchant, and Richard Green, a Blackwall shipbuilder had the idea of a training vessel on the Thames. The Worcester Committee was set up in 1861. Its first members Richard Green, Lord Alfred Paget, Sir George Chambers and Captain De St Croix instituted a subscription list and raised over £1000 within 6 months from shipowners, underwriters and merchants who had the foresight to invest in the future of their trade. The Admiralty loaned the HMS Worcester a 50 gun frigate of 1500 tons. In 1862 the Thames Marine Officer Training School was opened. She was to find her eventual home at Greenhithe in 1871 after temporary berths at Blackwall, Erith and Southend. To mark the occasion of mooring off Ingress Abbey the cadets fired a salute from the ships 18 pounder muzzle loading guns which caused the windows of a large number of houses in Greenhithe to break. As the college grew a larger ship was needed, and the Admiralty loaned the college the Frederick William a second rate line of battleship with 74 guns. She was renamed the Worcester and refitted in the Victoria Docks before being bought to Greenhithe in 1876. It was about this time the name of the school was changed to the Thames Nautical Training College, HMS Worcester. In 1938 the Cutty Sark was acquired by the college and berthed along side the Worcester. In 1939 during the war the cadets moved to Foots Cray Place near Sidcup, and the Worcester handed back to the Admiralty. The third Worcester arrived at Greenhithe on 15 January 1946. The official opening ceremony was held on Sat 2nd February. A letter of welcome on behalf of the village was sent by Mr W. S. Everard. The third Worcester was previously the Exmouth built in 1905 as the first specially commissioned training ship by the navy. At 314ft. in length, 53ft. beam and 181" mean draft with the upper portion of the hull mild steel and the lower half iron to prevent corrosion she represented all that was best of the old "wooden walls" and many of the improvements of the newer ships. In 1954 the Cutty Sark left Greenhithe to be docked permanently at Greenwich. In 1968 the Thames Nautical Training College became part of the Merchant Navy College at Greenhithe. The Worcester became redundant and was sold to be broken up in 1978.