The 1864 iron list includes metallic, ferrous, ferric and compound preparations; its wet Ferri Peroxidum Hydratum was used historically as an antidote to arsenic poisoning. It must be distinguished from dried Ferri Peroxidum and from later editions' reassignment of similar Latin names.
The officinal articles and preparations are:
Prepare the hydrated peroxide by inducing precipitation from the ferric solution with sodium hydroxide, collecting and washing the wet precipitate, and preserving it without drying in a covered vessel. The starting solution is Liquor Ferri Persulphatis, whose “persulphate” here means ferric sulfate, not a modern peroxydisulfate salt. Add the appropriately diluted ferric solution to the alkaline liquor with stirring, allow the precipitate to settle, collect it on a calico filter, and wash with distilled water until the washings no longer give a precipitate with barium chloride. This tests removal of soluble sulfate. The resulting fresh, hydrated material is kept wet; drying gives the separate dried preparation. [ref]
In modern chemical notation the precipitation can be idealised as
The fresh solid is a hydrated ferric oxide material with variable water content; the equation is not a claim that every pharmaceutical batch is one pure, crystalline iron hydroxide. Its historical use depended on binding dissolved arsenic into less available material in the digestive tract, especially the freshly precipitated, wet state. It was not a universal antidote to every metal or every stage of absorbed arsenic poisoning. Contemporary discussion explicitly identified the new hydrated peroxide as an arsenic antidote. [ref] [ref]
Modern treatment of significant arsenic poisoning concerns systemic toxicity and may involve specialist-directed chelation therapy; a nineteenth-century ferric paste is not the modern treatment standard. [ref]
For December 1865 the relevant official preparations are those of the 1864 British Pharmacopoeia; dose ranges must come from contemporary prescribing evidence, not be borrowed from later editions. The first edition specified identities and preparations without supplying a universal clinical dose for every article. The following are historical adult quantities from The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865), using its British entries rather than bracketed United States formulas. They are not current prescribing instructions or established safe limits. “Grain” is a unit of mass; “minim”, fluid drachm and fluid ounce are units of volume. One Imperial fluid drachm contains 60 minims, and one fluid ounce contains eight fluid drachms. A minim is not an arbitrary drop.[ref]
For arsenic, distinguish the elemental substance from its medicinal compounds. The relevant series comprises Acidum Arseniosum, Liquor Arsenicalis, Sodae Arsenias, Liquor Sodae Arseniatis and Ferri Arsenias. The contemporary ranges are arsenic trioxide about 1/60–1/12 grain; arsenical solution 2–5 minims, occasionally 10; crystalline sodium arsenate 1/12–1/2 grain, or its dried salt 1/20–1/4 grain; its official solution 5–30 minims; ferrous arsenate 1/10–1/8 grain. Hydrated and dried salts cannot be exchanged grain for grain. The two official arsenical solutions each contain four grains of their specified ingredient per fluid ounce, but the ingredients are different. The solution of arsenic and mercury discussed alongside them was non-official, and Liquor Arsenici Hydrochloricus was an addition in 1867: neither belongs in an unqualified list of 1864 preparations.[ref][ref]
For copper, the medicinal article is purified Cupri Sulphas, copper sulfate: 1/4–2 grains as a historical astringent or tonic, 5–8 grains as a historical emetic. An external solution was described as 1–10 grains or more per fluid ounce, depending on the intended local action. The anhydrous test reagent and copper compounds listed among analytical materials are not additional ordinary internal preparations. Neither the historical emetic use nor an external concentration authorises modern oral use.[ref]
For opium, the contemporary monograph gives powdered opium and Extractum Opii, 1/4–3 grains or more; Extractum Opii Liquidum, Tinctura Opii and Vinum Opii, 4–40 minims or more; Tinctura Camphorae cum Opio, 1–2 fluid drachms. These are the author's reported ranges, not maxima. His summary table differs, listing 3–30 minims for liquid extract and 1/2–4 grains for powdered opium; that internal variation should remain visible rather than being converted into an invented single official limit.[ref]
The compound oral opium preparations require their own quantities: Pilula Opii, 2 1/2 grains upwards; Pilula Plumbi cum Opio, 4–8 grains; Pulvis Cretae Aromaticus cum Opio, 10–60 grains; Pulvis Ipecacuanhae cum Opio, a reference quantity of 5 grains upwards; Pulvis Kino cum Opio, 10 grains upwards; Trochisci Opii, one to four lozenges. In the same order, the pill masses and powders contain approximately one part opium in 5, 8, 40, 10 and 20; each opium lozenge contains 1/10 grain. “Upwards” in the historical source does not establish a safe upper boundary: the required opium content, other ingredients and circumstances controlled the quantity. The lead-containing pill has an additional toxic constituent. Enema Opii supplies about one grain of opium in the official two-fluid-ounce enema; this is a rectal preparation, not an oral measure.[ref]
The external opium preparations, Emplastrum Opii, Linimentum Opii and Unguentum Gallae cum Opio, have no ordinary swallowed dose. For completeness the official isolated alkaloid series was Morphiae Hydrochloras, Liquor Morphiae Hydrochloratis, Suppositoria Morphiae, Trochisci Morphiae and Trochisci Morphiae et Ipecacuanhae. The reported historical quantities are morphine hydrochloride, 1/8–1 grain; its solution, 20 minims to two fluid drachms in the monograph; one suppository containing 1/4 grain; either kind of morphine lozenge, one to four, each containing 1/36 grain. The summary table gives a narrower upper quantity of one fluid drachm for the solution. These large historical ranges must not be interpreted as safe for a person without opioid tolerance. The solution contains four grains per fluid ounce. Neither a morphine-acetate preparation added later nor a non-official compound confection should be substituted for this 1864 series.[ref]
For belladonna, Extractum Belladonnae, 1/6–1 grain; Tinctura Belladonnae, 5–30 minims. Emplastrum Belladonnae, Linimentum Belladonnae and Unguentum Belladonnae are external preparations, not additional oral doses. The associated Atropia, Liquor Atropiae and Unguentum Atropiae likewise require their route to be stated: this author specifically discourages routine internal atropine administration and describes ophthalmic use of the solution. Its strength is four grains per fluid ounce; the ointment contains eight grains per ounce. These are historical formulation strengths, not a modern eye-drop or oral prescription. The atropine-sulfate series introduced in 1867 is not the 1864 series.[ref]
For Strychnia, strychnine, the historical range was 1/32–1/8 grain; Liquor Strychniae, 5–15 minims, the solution containing four grains per fluid ounce. If the botanical preparations yielding the alkaloid are included, powdered nux vomica, 1–3 grains; Extractum Nucis Vomicae, 1/4–2 grains; Tinctura Nucis Vomicae, 10–30 minims. The American editor already warned that the two-grain extract quantity was very large and that more than half a grain commonly risked adverse effects. Keeping that qualification is more faithful than presenting the printed upper range as routine or safe.[ref]
For cinchona bark, powdered yellow, pale or red bark, 10–60 grains; Decoctum Cinchonae Flavae and Infusum Cinchonae Flavae, 1–2 fluid ounces; Extractum Cinchonae Flavae Liquidum, 10–60 minims; Tinctura Cinchonae Flavae and Tinctura Cinchonae Composita, 1–2 fluid drachms. The associated Tinctura Quiniae Composita was given at 1–2 fluid drachms. The isolated official quinine sulfate, Quiniae Sulphas, was listed at 1–10 grains, with larger quantities discussed for particular intermittent fevers. Ferri et Quiniae Citras, the official iron-and-quinine preparation, was listed at 5–20 grains. Other cinchona alkaloids discussed as possible remedies do not thereby become official preparations. Strength in bark equivalents also does not guarantee a fixed amount of extracted quinine.[ref]
These figures answer a historical materia medica question. Current drug safety requires the exact modern product, route, indication and patient factors; poisonous nineteenth-century “tonics” and emetics are not revived by accurate transcription of their period doses. Strychnine can cause severe painful convulsions; opioids can depress breathing; and inorganic arsenic is a toxic and carcinogenic exposure. Those facts undermine any reading of the historical numbers as a self-treatment schedule.[ref][ref][ref]