683, with the rank of second lieutenant, on 16 June 1838, spending his first five years on Ordnance Survey work in Wales, Ireland and Northern England.

His service over the years, before his retirement with the rank of major-general in 1873, took him to Hong Kong, Sydney, Auckland, Wellington, Wanganui, Hobart Town, London, Waltham Abbey, Aldershot, Corfu, Malta, Chatham and Dover.

Collinson, accompanied by one sergeant and thirty-three sappers, left Woolwich on the HEICS Mount Stewart Elphinstone for Hong Kong on 24 May 1843 and arrived there on 7 October.

He also added soundings and other nautical information from the Admiralty chart of Hong Kong by Captain Edward Belcher, RN, HMS Sulphur.

Only one stone trig station now remains, revealed by a University of Hong Kong team on 3 October 2015, at Lei Yue Mun Park.

[15]: 25  His drawings were of such an admirable standard that Major Edward Aldrich, RE, illustrated his 21 July 1846 report on the erection of Ordnance buildings in Hong Kong with them.

[16] On 11 June 1846, Collinson embarked on the Emily Jane for Sydney, New South Wales, and after a brief stay there, he sailed for Auckland, New Zealand, on the trading brigantine Terror, arriving on 19 September 1846 to difficult times of conflict between the Pakeha settlers and the native Māori population.

[18] Liddell, age 20 years, had left England on the brig Richard Dart on 5 April but, by the time of Bolton’s note, had perished with a good part of his detachment of twenty-eight Royal Sappers and Miners when the ship struck rocks at Prince Edward Island of the Prince Edward Islands, sub-antarctic Indian Ocean, on 19 June 1849.

In consequence, Lieutenant Francis Rawdon Chesney, RE, set out for New Zealand in March 1850 with a detachment of twenty-seven men of the Royal Sappers and Miners.

Whilst at Hobart Town, Van Dieman’s Land, on Tuesday, 26 March 1850, Collinson forwarded his paper 'On Timber Trees of New Zealand' to the Royal Society of Van Dieman’s Land along with samples of timber and dried leaves of the principal forest trees found in the southern part of New Zealand, and was admitted into the Society at its April meeting.