Green’s Dictionary of Slang

(drugs) Chinese opium prepared for smoking.

1882		A. Trumble Heathen Chinee 31: [T]he needle is forced down into the small hole in the bowl, thus levelling off the bottom of the pea (chandootschandu).
1889		Leeds Mercury 25 Jan. 3/2: A little room, opento the street [...] This is a ‘Churrus shop’ or —Chandu’.
1895		Dundee Courier 23 Apr. 2/4: The ‘comparatively rare and novel habit of smoking preparations of opium known as chandu’.
1907		Manchester Courier 3 Jan. 6/4: There was a marked dexcline due to an enhancement of the price at which the farmers were allowed to sell ‘chandu’.
1915		T. Burke Nights in Town 87: Taking a jolt of ‘chandu’ in a Limehouse room.
1919		‘Sax Rohmer’ Dope 89: Chandu is a key to another life [...] Chandu is misunderstood in Europe; in Asia it is the companion of aesthete’s leisure. [Ibid.] 91: ‘Someone smokes the chandu cigarettes,’ she said speaking in a low tone.
1922		E. Murphy Black Candle 112: The smoker requires a long steel yenkok [sic], or toasting pin, with which to hold the gum of chandu.