The 1864 preparations contain either crude opium or its aqueous Extractum Opii; those quantities must be distinguished from a quantity of isolated morphine. The following are the officinal opium preparations. Ratios for solids mean the mass fraction in the compounded preparation; liquid strengths specify mass per volume or the actual ingredients used.
- Emplastrum Opii: powdered opium in resin plaster: 1 in 10.
- Enema Opii: opium tincture 30 minims with starch decoction 2 fluid ounces. Thus the tincture is 1 volume to 32 volumes of vehicle, before mixing.
- Extractum Opii: aqueous solvent extraction of 1 avoirdupois pound of sliced opium with 6 Imperial pints of distilled water, in three successive portions, followed by evaporation. The prescribed starting quantities do not impose a fixed yield or a universal crude-drug-to-extract potency ratio.
- Extractum Opii Liquidum: Extractum Opii 1 avoirdupois ounce, distilled water 17 fluid ounces, rectified spirit 3 fluid ounces: 1 ounce of extract to the pint of liquid ingredients.
- Linimentum Opii: equal volumes of opium tincture and soap liniment: half the tincture's nominal opium strength.
- Pilula Opii: powdered opium with hard soap: 1 in 5 of the nominal pill ingredients.
- Pilula Plumbi cum Opio: powdered opium with lead acetate and confection of roses: 1 in 8.
- Pulvis Cretae Aromaticus cum Opio: powdered opium with aromatic chalk powder: 1 in 40.
- Pulvis Ipecacuanhae cum Opio: powdered opium with ipecacuanha and potassium sulfate: 1 in 10.
- Pulvis Kino cum Opio: powdered opium with kino and cinnamon: 1 in 20.
[ref]
The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865). Papaverceae, part 2, British formulas outside the bracketed American additions; underlying revision dated May 1864
- Tinctura Camphorae cum Opio: opium 40 grains to 1 Imperial pint of proof spirit, with benzoic acid, camphor and anise oil: 2 grains of opium per fluid ounce.
- Opium tincture, Tinctura Opii: powdered opium 1½ avoirdupois ounces to 1 Imperial pint of proof spirit. Nominally this is 32.8125 grains per fluid ounce, or approximately 1 grain per 14.63 minims.
- Trochisci Opii: 72 grains of Extractum Opii in 720 lozenges: one tenth of a grain of extract per lozenge.
- Unguentum Gallae cum Opio: powdered opium 32 grains added to 1 avoirdupois ounce of gall ointment. The actual nominal total is grains, giving 32/469.5 by mass, approximately 1 in 14.67; “32 grains to the ounce of ointment taken” is not 32 grains per final ounce.
- Vinum Opii: powdered opium 1½ avoirdupois ounces, sherry 1 Imperial pint: the tincture's nominal opium proportion, in a different solvent. This formula uses crude opium, not Extractum Opii.
[ref]
The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865). Papaverceae, part 3, British tincture, lozenge, ointment and wine formulas
The arithmetic uses the new avoirdupois ounce of 437.5 grains, not the old apothecaries' ounce of 480 grains. These are historical formulation proportions, not modern assays of morphine delivered after solvent extraction. Confectio Opii was omitted in 1864, and this edition's Vinum Opii contains no spices. The separate morphine hydrochloride preparations—Liquor Morphiae Hydrochloratis, Suppositoria Morphiae, Trochisci Morphiae, and Trochisci Morphiae et Ipecacuanhae—contain an isolated alkaloid salt rather than crude opium. [ref]
The Prescriber's Analysis of the British Pharmacopoeia by John Birkbeck Nevins (1864). pp. 11–12, 39 and 75–76
The compositions must be specified ingredient by ingredient; the two alkaloidal solutions contain 4 grains per nominal fluid ounce, but one contains a morphine salt and the other strychnine.
Pulvis Jalapae Compositus contains powdered jalap 5 avoirdupois ounces, potassium hydrogen tartrate 9 avoirdupois ounces, and powdered ginger 1 avoirdupois ounce. Thus the mass proportions are 5:9:1, and jalap supplies one third of the powder's mass. This is a compound purgative, not pure jalap resin. [ref]
The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865). Convolvulaceae, Jalapa, compound powder
Pilula Scillae Composita contains powdered squill 1¼ avoirdupois ounces, powdered ginger, ammoniacum and hard soap 1 avoirdupois ounce each, with treacle 2 avoirdupois ounces, or sufficient to make a pill mass. Using the specified 2 avoirdupois ounces of treacle, the whole is 6¼ avoirdupois ounces and contains one fifth squill by mass. The allowance of sufficient treacle makes consistency a compounding requirement, not a claim that every moist pill batch has an analytically exact 20% squill content. [ref]
The Essentials of Materia Medica and Therapeutics by Alfred Baring Garrod (1865). Liliaceae, British compound squill pill, distinguished from bracketed American formula
Liquor Morphiae Hydrochloratis contains morphine hydrochloride 4 grains, dilute hydrochloric acid 8 minims, rectified spirit 2 fluid drachms and distilled water 6 fluid drachms. Its conventional strength is ½ grain of morphine hydrochloride per fluid drachm, not ½ grain of free morphine. The small quantity of hydrochloric acid maintains an acid solution. [ref]
Liquor Strychniae contains strychnine 4 grains, dilute hydrochloric acid 6 minims, rectified spirit 2 fluid drachms and distilled water 6 fluid drachms. Dissolve the strychnine in the acid mixed with part of the water, using the prescribed assistance of heat, then add the spirit and remaining water. Its conventional strength is ½ grain of strychnine per fluid drachm. Acid promotes solubility by forming a soluble salt of the alkaloid. [ref]
For the last two solutions, the stated historical strengths use the nominal 8 fluid drachms of spirit and water. The extra few minims of dilute acid must still appear in the actual recipe; treating all ingredient volumes as perfectly additive would not give an exact modern analytical concentration.
Fresh rainwater is ordinarily soft because evaporation leaves most nonvolatile dissolved salts behind; “always” is an idealization, not an exceptionless law. Water hardness is principally caused by dissolved calcium and magnesium ions. Water vapour rising from a hard-water source does not carry these ions with it as vapour. Condensation consequently supplies low-mineral water before contact with dust, surfaces or soil. Mineral particles, sea spray and a collecting surface can add salts, so actual collected rainwater need not have zero water hardness. Nor does softness establish purity or freedom from microorganisms.[ref]
Hardness in Drinking-water by World Health Organization. Chemical fact sheet, natural waters and the low mineral content of rainwater
The historically appropriate quantitative principle is soap titration of water hardness. Soluble soap reacts with hardness-producing ions to form poorly soluble salts, using up soap before a persistent lather can form. For a representative carboxylate soap,Magnesium behaves similarly. Once the dissolved hardness-producing ions have substantially reacted, additional soap can sustain the specified lather. The endpoint is therefore an operational observation under standardized shaking, standing time, temperature and sample volume; it is not the first transient bubble.
Use a measured volume of sample in a stoppered vessel with enough headspace for shaking. Add a soap solution of known strength incrementally from a burette, shaking in a reproducible way, until the chosen persistent-lather endpoint appears. Determine a blank with a corresponding amount of soft or distilled water, because some soap is needed for the lather even when no hardness salts are present. Standardize the soap against a reference solution containing a known calcium amount, expressed as an equivalent mass of calcium carbonate. This standardization is essential: the apparent strength cannot safely be inferred from the mass of an incompletely characterized commercial soap.
Let be the sample volume in millilitres, the soap titre in millilitres and the corresponding blank. If is the standardized capacity in milligrams of calcium carbonate equivalent per millilitre of soap solution, thenFor a standard containing milligrams of calcium carbonate equivalent and requiring blank-corrected titre , . This makes the measurement quantitative without assuming an unreported soap concentration or inventing a sample titre. Historical results could instead be stated as grains of calcium carbonate equivalent per gallon, provided the gallon convention was specified.
Repeating the examination after controlled boiling, cooling, removal of the precipitate and restoration of the original volume estimates the residual or permanent hardness. The reduction estimates the boiling-removable fraction, often called temporary hardness. A representative reaction isCarbonate equilibria and magnesium chemistry make this more subtle than assuming every dissolved salt is destroyed by boiling. Very hard samples may need measured dilution; magnesium, other metal ions and contamination can disturb the lather endpoint. Thus the soap result is an experimentally calibrated hardness equivalent, not an exact identification of every original salt.
Saponification of triglycerides 2026-10-18
A triglyceride contains three ester linkages joining glycerol to fatty acid-derived acyl groups. Complete saponification therefore consumes three hydroxide equivalents per triglyceride, yielding one glycerol and three fatty acid carboxylates.[ref]
27.2 Soap. Organic Chemistry by John McMurry; §27.2, opening chemical definition and fat hydrolysis equation
Writing the three hydrocarbon groups separately allows their compositions to differ:This is the preceding ester chemical equation applied three times: each linkage supplies one carboxylate, and each formerly esterified oxygen on the glycerol scaffold gains one hydrogen. The two sides retain the same three groups and have net electric charge .
Soap consists of sodium or potassium salts of long-chain fatty acids. Its carboxylate head is hydrophilic, while its long hydrocarbon tail is hydrophobic. This makes it an amphiphile and a surfactant: the tails can associate with grease while the heads remain exposed to water, helping disperse grease for rinsing. An acetate ion is also a carboxylate, but lacks the long hydrophobic tail that gives soap this cleaning role.[ref]
27.2 Soap. Organic Chemistry by John McMurry; §27.2, chemical definition and paragraphs on the ionic head, hydrocarbon tail and removal of grease
Soap 2026-10-18
Soap consists of sodium or potassium salts of long-chain fatty acids. Its hydrophilic carboxylate head and hydrophobic hydrocarbon tail make it an amphiphile; saponification of triglycerides produces these salts.
Soap titration of water hardness Created 2026-10-31 Updated 2026-11-05
Water hardness Created 2026-10-31 Updated 2026-11-05
