For a long time, medical recipes were written in Latin, often using special symbols to denote weights and measures.
The use of different measure and weight systems depending on the purpose was an almost universal phenomenon in Europe between the decline of the Roman Empire and metrication.
[7] This was connected with international commerce, especially with the need to use the standards of the target market and to compensate for a common weighing practice that caused a difference between actual and nominal weight.
The apothecaries' pound was divided into its own special units, which were inherited (via influential treatises of Greek physicians such as Dioscorides and Galen, 1st and 2nd century) from the general-purpose weight system of the Romans.
New terms and symbols introduced by the London College of Physicians (octarius, minim) were subsequently adopted by the Pharmacopoeias of the United States and Dublin.
In fact, the units were qualitatively different because the traditional drop, by the nature of how it was measured, did not actually correspond to a single definite volume.
[38]) Along with the new name of minim, the London Pharmacopoeia of 1809 prescribed a new method of measuring the smallest unit of volume using a graduated glass tube.
[42] There were also commonly used, but unofficial divisions of the Apothecaries' system, consisting of:[43] In the United States, similar measures in use were once: [citation needed] The cited book states, "In almost all cases the modern teacups, tablespoons, dessertspoons, and teaspoons, after careful test by the author, were found to average 25 percent greater capacity than the theoretical quantities given above, and thus the use of accurately graduated medicine glasses, which may be had now at a trifling cost, should be insisted upon.
[47][48] This is close to the classical Greek weight system, where a mina (corresponding roughly to a Roman libra) was also divided into 100 drachms.
[49] With the beginning of metrication, some countries standardized their apothecaries' pound to an easily remembered multiple of the French gramme.
The British troy pound retained its value of 373.202 g until in 2000 it was legally defined in metric terms, as 373.2417216 g.[51] (At this time its use was mainly confined to trading precious metals.)
Galen and Dioscorides (who had used the Graeco-Roman weight system) were among the most important authorities, but also Arabic physicians, whose works were systematically translated into Latin.
While there will naturally have been some changes throughout the centuries, this section only tries to give a general overview of the situation that was recorded in detail in numerous 19th-century merchants' handbooks.
Due in part to the political conditions in what would become a united Kingdom of Italy only in 1861, the variation of apothecaries' systems and standard weights in this region was enormous.
[48][61] The apothecaries' pound in Venice had exactly the same subdivisions as those in the non-Romance countries, but its total weight of 301 g was at the bottom of the range.
During the Habsburg reign of 1814–1859 an exception was made for Venice; as a result, the extreme weights of 301 g and 420 g coexisted within one state and in immediate proximity.
In Dubrovnik (called "Ragusa" until 1909) its use was partially continued for a long time in spite of the official Habsburg weight reform.
[62] The national French standard until 1799 was based on a famous artifact called the Pile de Charlemagne [fr], which probably dates back to the second half of the 15th century.
In Bruges, Amsterdam, Antwerp and other Flemish cities, a "troy" unit ("trooisch pond") was also in use as a standard for valuable materials and medicine.
The Flemish troy pound became the standard for the gold and apothecaries' system in the United Kingdom of the Netherlands; it was also used in this way in Lübeck.
The British apothecaries' system was based on the troy pound until metrication, and it survived in the United States and Australia well into the 20th century.
[9][68] In the Middle Ages the Imperial Free City of Nuremberg, an important trading place in the south of Germany, produced large amounts of nesting weight pieces to various European standards.
[74] Austria and the states of the Habsburg monarchy officially had a different standard since 1761, and Prussia, followed by its neighbours Anhalt, Lippe and Mecklenburg,[75] would diverge in the opposite direction with a reform in 1816.
[59] The weight of an apothecaries' pound of 12 ounces was increased to a value that was later (after the kilogramme was defined) found to be 420.009 g; this was called the libra medicinalis major.
The 1770 edition of the pharmacopoeia Dispensatorium Austriaco-Viennense still used the Nuremberg standard libra medicinalis minor, indicating that even in the Austrian capital Vienna it took some time for the reform to become effective.
When Austria started producing scales and weight pieces to the new standard with an excellent quality/price ratio, these were occasionally used by German apothecaries as well.
Serious work on a "scientific" system was started in France under Louis XVI, and completed in 1799 (after the French Revolution) with its implementation.
[77] From 1803 to 1815, all German regions west of the River Rhine were French, organised in the départements Roer, Sarre, Rhin-et-Moselle, and Mont-Tonnerre.
A large part of the Palatinate fell to Bavaria, but having the metric system it was excepted from the Bavarian reform of weights and measures.
[81] The abolishment of the apothecaries' system meant that doctors' prescriptions had to take place in terms of the current civil weight: grammes and kilograms.