Reports of Trials for Murder by Poisoning; / by Prussic Acid, Strychnia, Antimony, Arsenic, and Aconita. Including the trials of Tawell, W. Palmer, Dove, Madeline Smith, Dr. Pritchard, Smethurst, and Dr. Lamson, with chemical introduction and notes on the poisons used

by G. Lathom Browne; active 19th century C. G. Stewart

19. A solution of chloride of arsenic has been employed for “bronzing” metals. The fumes would be highly pernicious.

20. Ritter, of Rouen, states that glucose or starch-sugar frequently contains arsenic, derived from the sulphuric acid employed in its manufacture being made from arsenical pyrites. He finds that by this means the arsenic is introduced into beer brewed with glucose, into confectionery, syrups, liqueurs, &c. (Reimann’s Färber Zeitung, No. 3, 1878.)

21. It is said that certain paper collars and cuffs which are extensively made in America have proved poisonous from containing a considerable proportion of arsenic. (Les Mondes, Nov. 11th, 1880.)[135]

22. Speculum Metal, for telescope mirrors, is an alloy of copper, tin, and 3 per cent. of arsenic.

23. In America, a paper soaked in a solution of arsenic and other drugs is burnt, and the smoke inhaled for asthma and bronchitis. (Year Book of Pharm., 1873, p. 345.)

24. Traces occur in mineral waters.

SULPHIDES OF ARSENIC.

Orpiment, As₂S₃, Auripigmentum, or King’s Yellow, trisulphide of arsenic, obtained by precipitating a solution of arsenic with sulphuretted hydrogen, is a yellow inodorous powder, insoluble in water and in hydrochloric acid, but slowly oxidizing in air to arsenious acid, and therefore poisonous. It is found native. By heat it melts to a reddish liquid: if air be excluded, it volatilizes at about 700° C., and condenses unchanged: if air be present, it is oxidized to sulphur dioxide and arsenic trioxide, which condenses in the crystals before-mentioned. It is soluble in alkalies and their carbonates, and reprecipitated by hydrochloric acid. Commercial “King’s Yellow,” formerly used as a pigment, but now replaced by Chromate of lead, is a very poisonous mixture of As₂ O₃ and As₂ S₃. It is sometimes employed in printing indigo. A mixture of orpiment, water and lime is used in the East as “Rasma” (see page 320) for a depilatory. In a corpse, by putrefaction, the arsenic is frequently converted into sulphide.

Realgar, the disulphide, As₂ S₂, is red, exists as a mineral, and is also made artificially for fireworks. It contains about 75 per cent. of arsenic, but varies. Formerly it was used as a pigment, and in tanning to remove hair.