Pituri  Pituri is a mixture of leaves and wood ash traditionally chewed as a stimulant (or, after extended use, a depressant) by Aboriginal Australians widely across the continent. Leaves are gathered from any of several species of native tobacco ("Nicotiana") or from at least one distinct population of the species "Duboisia hopwoodii". Various species of "Acacia", "Grevillea" and "Eucalyptus" are burned to produce the ash. The term "pituri" may also refer to the plants from which the leaves are gathered or from which the ash is made. Some authors use the term to refer only to the plant "Duboisia hopwoodii" and its leaves and any chewing mixture containing its leaves. The earliest record of Aboriginal chewing is found in Joseph Banks's 1770 journal: Edmund Kennedy, in his 1847 record of a journey beyond the Barcoo River, described a leaf, tasting strong and hot with the aroma and flavour of tobacco, being chewed by the Aboriginal people. Burke and Wills, on their ill-fated 1861 journey through inland Australia, were given food by local Aboriginal people and also "stuff they call bedgery or pedgery" to chew, which Wills found highly intoxicating even in small amounts. A report from Western Australia described the smoke from burning pituri leaves being used as an anaesthetic during surgical operations. Other nineteenth century reports said chewing pituri made old men seers, induced valour in warfare and allowed Aboriginal people to walk hundreds of kilometres without food or water; and a 1901 report claimed they "will usually give anything they possess for it". These reports generated significant curiosity within the local scientific community about the identity of the source plant and the identity of pituri's active chemical constituent. In 1872, Joseph Bancroft, a Brisbane physician, received pituri leaves from south-west Queensland, and performed the first pharmacological investigation. He reported that extract of pituri is toxic to frogs, rats, cats and dogs, with a very small dose diluted in water and injected under the skin causing death after respiratory arrest in some cases. Bancroft received more specimens in 1877, collected on an expedition to north-west Queensland by the explorer William Hodgkinson and identified by Ferdinand von Mueller as the broken leaves and twigs of the shrub "Duboisia hopwoodii". Hodgkinson was taken aback by Bancroft's assessment of pituri's toxicity, and said it was as benign as tobacco: Bancroft took Hodgkinson's samples to Britain and France where English researchers concluded the plant "is more closely allied to tobacco" and a Parisian chemist identified the active constituent as nicotine.