In 1827, with the support of Sir George Murray, Mitchell became Assistant Surveyor General of
New South Wales with the right to succeed
John Oxley. Oxley died the following year, and on 27 May 1828, Mitchell became Surveyor General. including sketches and plans of Sydney,
Emu Plains, the
Blue Mountains, Victoria Pass, roads to
Bathurst,
Wisemans Ferry, and indigenous Australians. As Surveyor General, Mitchell also completed maps and plans of Sydney, including
Darling Point,
Point Piper,
the city, and
Port Jackson. In 1834 he was commissioned to survey a map of the
Nineteen Counties. The map he produced was done with such skill and accuracy that he was awarded a knighthood. Around this time, a portrait of Mitchell was painted showing him in the uniform of Major of the 1st Rifle Brigade of the 95th Regiment, complete with whistle used to direct the movement of troops. During his tenure in New South Wales, Mitchell led four extensive and historically significant surveying expeditions into the interior of eastern Australia.
First expedition In 1831, a runaway convict named
George "The Barber" Clarke (a monument to whom exists at Barber's Lagoon near
Boggabri and who had lived with the
Kamilaroi people in the area for several years) claimed that a large river called Kindur flowed north-west from the Liverpool Ranges in New South Wales to the sea.
Charles Sturt believed that the Murray-Darling system formed the main river system of New South Wales and Mitchell wanted to prove Sturt wrong. Mitchell formed an expedition consisting of himself, assistant surveyor George Boyle White and 15 convicts who were promised remission for good conduct. Mitchell took 20 bullocks, three heavy drays, three light carts and nine horses to carry supplies, and set out on 24 November 1831 to investigate the claim. On reaching
Wollombi in the Hunter Valley, the local assistant surveyor, Heneage Finch, expressed a desire to join the expedition which Mitchell approved, provided he first obtain extra provisions and rendezvous later. The expedition continued northward, and having climbed the
Liverpool Range on 5 December, they found an Aboriginal tribe who had fled from their home in the Hunter Valley and were suffering from what appeared to be
smallpox. On 8 December they arrived at
Quirindi and by 11 December the expedition had reached Wallamoul Station near
Tamworth, the northern extent of white settlement at the time. After the fruitless search for Cunningham, Mitchell decided to continue the expedition. He was assisted by a local unnamed elder who provided a guide called Tackijally. This man led Mitchell downstream along the waterholes adjacent to the Bogan River as far as
Nyngan. Tackijally left them at this point and the group was soon involved in a brief confrontation after they startled an Aboriginal man at a waterhole. The man, who was shot in the hand, had his wounds dressed by the group and later departed. They proceeded down the Bogan, encountering several gatherings of people to which Mitchell gave
tomahawks and pieces of an old sword. On 25 May the junction with the
Darling River was reached. Here, on a high point of land which bore many Aboriginal grave sites, Mitchell decided to build a fort as he realised that they "had not asked permission to come there" and he needed a stockade for "stout resistance against any number of natives". He named it
Fort Bourke in honour of the Governor,
Richard Bourke. They encountered many tribes as they headed south, with Mitchell documenting the agricultural practices of some, such as the harvesting of
Panicum decompositum, and the large permanent dwellings of others. One clan appeared more hostile than others, kicking up dust and spitting at party members. Mitchell acknowledged that his group were "rather unceremonious invaders of their country" but inflamed tensions by firing a pistol at a tree. Mitchell wrote that "the more they saw of our superior weapons...the more they shewed their hatred and tokens of defiance." The party continued downriver, meeting with friendlier locals, passing through villages and noting the construction of their tomb-sites. The places where this and other Mitchell expeditions were most assailed by Aboriginal Australians, including the location of Cunningham's killing, are marked on an 1836 map produced by Mitchell.
Third expedition with people from Lake Benanee The goal of Mitchell's third expedition was to explore and survey the lower part of the
Darling River, with instructions to head up the
Murray River and then return to the settled areas around
Yass. Second in command was assistant surveyor
Granville Stapylton. A
Wiradjuri man named
John Piper was also recruited and 23 convicts and
ticket of leave men made up the rest of the party. The group set out from a valley near
Mount Canobolas on 17 March 1836, and made their way to Boree and the Bogan River as on previous journeys, then veered south to the Kalare or
Lachlan River to approach the Darling from its southern end where it joined the Murray. The party was guided by various Aboriginal people such as "Barney" along the Lachlan, passing
Lake Cargelligo, as John Oxley did in 1817. At this place they met with a large clan from which a number of people joined the expedition and gave vital information about waterholes, as the Lachlan was drying out. Piper also obtained a "good, strong woman" from this tribe. On 2 May they arrived at Combedyega where an Aboriginal widow named
Turandurey with her four-year-old daughter Ballandella also joined the expedition as a guide. She remembered Oxley from nineteen years earlier and Sturt as well, and knew the lower Lachlan. The
Murrumbidgee River was reached on 12 May, but at a point downstream from the junction with the Lachlan. Around 75 shots were fired with Piper later being told that seven Barkindji were killed and four wounded. Mitchell wrote about the loss of life in his journal, describing the Barkindji as "treacherous savages", and detailing how his men had chased them away, "pursuing and shooting as many as they could". This section was withheld from Mitchell's report when it was released to the public in Sydney. Mitchell named the hill near to where the mass-shooting occurred
Mount Dispersion and in May 2020 it was heritage-listed as the Mount Dispersion Massacre Site Aboriginal Place.
Onwards The expedition continued down the Murray River, encountering a major Aboriginal grave-site at
Red Cliffs. On 31 May they arrived close to the junction of the Murray with a "green and stagnant" waterway. Local people advised Piper that this was the Darling River. Mitchell did not believe it, and only when he travelled upstream for some distance, coming across the same type of burial mounds that he had seen in 1835, did he acknowledge that "this hopeless river" was the Darling. He turned back and headed upstream on the Murray to rejoin Stapylton at the depot. The reunited expedition now travelled south-east following the Murray. They passed
Swan Hill on 21 June and encountered a group of native inhabitants at
Lake Boga. These people were angry at Piper for "bringing whitefellows" to their country and threw spears at him. Piper shot one of them dead. Mitchell noted the local people's practice of making large nets that spanned above the river to catch waterfowl and also came across unusual animals such as the now extinct
Southern pig-footed bandicoot.
Fourth expedition Mitchell's fourth expedition was into northern interior of the colony (a region now part of
Queensland) in 1845–46. He was convinced that a significant river must flow north-west into the
Gulf of Carpentaria, and finding this river was the main focus of the endeavour. On 15 December 1845 Mitchell started from Boree near
Orange with a large party of 32 people including
Edmund Kennedy as second in command (later speared to death at Escape River near
Cape York). The
Wiradjuri man named Piper from his previous expedition was also a member.
Yuranigh (also Wiradjuri) and a ten year old boy from the lower
Bogan River named "Dicky" were also assigned as guides. The party travelled north along the Bogan where a war between the British and the Indigenous inhabitants was at that time occurring. Mitchell noted areas where the British had been pushed back, abandoning their farmhouses which were subsequently burnt down by the local people. Mitchell stated "All I could learn about the rest of the tribe was, that the men were almost all dead, and that their wives were chiefly servants at stock stations along the Macquarie." In January 1846, they left the Bogan and started following the
Macquarie River where Mitchell was informed of Pipers' intention to leave the expedition. Mitchell ordered him back to
Bathurst, accompanied by Corporal Graham. Near the
Macquarie Marshes the harvesting of
native millet by Aboriginal people to make bread was recorded and a local man named Yulliyally guided the group to the
Barwon River. From here two brothers from a nearby clan led Mitchell to vital waterholes near the
Narran River. Mitchell "blushed inwardly for our pallid race" knowing that "white man's cattle would soon trample these holes into a quagmire of mud." More bundles of harvested millet lay for miles along their journey up the Narran. Mitchell then received a message from his son, Roderick Mitchell, a Crown Lands Commissioner who had previously been to the area, which recommended following the
Balonne and the
Culgoa rivers north. They encountered many Indigenous people who guided the group along the way. On 12 April 1846 Mitchell came to a natural bridge of rocks on the main branch of the Balonne which he called St. George Bridge, now the site of the town of
St George. Kennedy was left in charge of the main body here, and was instructed to follow on slowly while Mitchell pushed ahead with a few men. Mitchell followed the Balonne to the
Maranoa, and the Cogoon (now called Muckadilla Creek, near Roma). This rivulet led him to an area with an "abundance of good pasturage" in which stood a solitary double topped hill that he named Mount Abundance, on which grew a species of
bottle tree. He then crossed to the Maranoa and awaited Kennedy's arrival. Kennedy, who had trouble with local inhabitants trying to burn down his camp, rejoined Mitchell on 1 June 1846. Mitchell traversed the country at the head of the Maranoa, on one occasion discharging his rifle over the heads of the Indigenous people to gain "peaceful occupation of the ground". He sighted the headwaters of the
Warrego and
Nogoa Rivers, then came across the upper reaches of the
Belyando River which they followed for a considerable distance. This river's name was given to Mitchell by Indigenous residents before the expedition's dogs chased them away, biting at their legs. Being a tributary of the
Burdekin River, a waterway already visited by
Ludwig Leichhardt on his expedition to
Port Essington in 1845, Mitchell was dismayed to find that he was approaching ground already explored by Europeans. He returned to the head of the Nogoa and struck west, meeting with a tribe who caught
emus with nets. He encountered a river which he was certain was the fabled waterway that would flow north-west to the Gulf of Carpentaria. He followed it until he came across a large clan of Aboriginal people living in permanent huts on the banks of a lagoon. He called this place Yuranigh Pond after his Wiradjuri guide and decided to return home. In honour of the British sovereign of the time, he named the waterway, Victoria River. On the homeward journey Mitchell noticed the well known
grass that bears his name. They trekked back along the Maranoa River to St.George Bridge, arriving in Sydney 20 January 1847. Later in 1847, Kennedy proved beyond doubt that the Victoria in fact did not continue north-west, but turned south-west and joined
Cooper Creek. He renamed the watercourse the
Barcoo River from a name mentioned by local Aboriginal people. == Later career ==