By digging around in the Bara Simla Hills, part of the Lameta formation near Jabalpur, he unearthed several petrified trees, as well as some fragmentary dinosaur fossil specimens.

This was first published in the first volume of his Journey through the kingdom of Oude in 1848-1850 (1858)[12] and reprinted in 1852 as An Account of Wolves Nurturing Children in Their Dens, by an Indian Official and in The Zoologist (1888 12 (135): 87–98).

Dating back as early as the 1300s, Thugs were a secret criminal group, partly hereditary in membership, who specialized in the murder by strangulation of travelers as a prelude to theft.

Thugs had been known to native rulers and occasionally to Europeans, but the scope of their crimes was not appreciated (later estimated at least in the tens of thousands of victims across India).

In 1835, Sleeman captured "Feringhea" (one of the inspirations for the character Syeed Amir Ali in Confessions of a Thug is based) and got him to turn King's evidence.

Detection was only possible by means of informers, for whose protection from the vengeance of their associates a special prison was established at Jabalpur (at the time Jubbulpore).

[19] Established in Regulation XXVII of 1871, the Criminal Tribes Act (CTA) sought to identify, surveil, and 'rehabilitate' groups of Indians who, due to their itinerancy, presented a challenge to British authority.

Thuggee Act of 1836, which set a legal precedent because it allowed individuals to be convicted based solely on affiliation to a criminal group, with no evidence of having committed a crime.

[22] He died and was buried at sea near Ceylon on a recovery trip to Britain in 1856, just six days after being awarded the Order of the Bath (KCB).

[23] Whilst in Jubbulpore, he married Amélie Josephine, the daughter of Count Blondin de Fontenne, a French nobleman.