(US: dram )
|1 pound||12 ounces||96 drachms||288 scruples||5,760 grains|
|1 ounce||8 drachms||24 scruples||480 grains|
|1 drachm||3 scruples||60 grains|
|1 scruple||20 grains|
|373 g||31.1 g||3.89 g||1.296 g||64.8 mg|
The use of different measure and weight systems for different purposes was an almost universal phenomenon in Europe between the decline of the Roman Empire and metrication. This was connected with international commerce (expedience of using the standards of the target market) and with the widespread practice of "inclined-beam weighing" of less valuable goods. In the 19th century, most European countries or cities still had at least a "commercial" or "civil" system (such as the English avoirdupois system) for general trading, and a second system (such as the troy system) for precious metals such as gold and silver. The system for precious metals was usually divided in a different way than the commercial system, often using special units such as the carat. More significantly, it was often based on different weight standards.
The apothecaries' system often used the same ounces as the precious metals system, although even then the number of ounces in a pound could be different. The apothecaries' pound was divided into its own special units, which were inherited (via influential treatises of Greek physicians such as Dioscorides and Galen, first and second century) from the general-purpose weight system of the Romans. Where the apothecaries' weights and the normal commercial weights were different, it was not always clear which of the two systems was used in trade between merchants and apothecaries, or by which system apothecaries weighed medicine when they actually sold it. In old merchants' handbooks the former system is sometimes referred to as the pharmaceutical system, and distinguished from the apothecaries' system.
(US: dram )
|1 ℔||12 ℥||96 ʒ||288 ℈||5,760 gr.|
|1 ℥||8 ʒ||24 ℈||480 gr.|
|1 ʒ||3 ℈||60 gr.|
|1 ℈||20 gr.|
|373 g||31.1 g||3.89 g||1.296 g||64.8 mg|
Before introduction of the imperial units in the UK, all apothecaries' measures were based on the wine gallon, which survived in the US under the name liquid gallon or wet gallon.
The wine gallon was abolished in Britain in 1824, and this system was replaced by a new one based on the newly introduced imperial gallon. Since the imperial gallon is 20% more than the liquid gallon, the same is true for the imperial pint in relation to the liquid pint. This explains why the number of fluid ounces in both systems had to be different to make them of approximately the same size. As a result, the modern UK fluid ounce is 4% less than the US fluid ounce, and the same is true for the smaller units. For some years both systems were used concurrently in the UK.
Until around 1900, medical recipes and most European pharmacopœias were written in Latin. Here is a typical example from the middle of the 19th century.
|Infusion of Dandelion, &c.|
|℞||Infusi Taraxaci, f℥iv.||4 fluid ounces of infusion of dandelion|
|Extracti Taraxaci, fʒij.||2 fluid drachms of extract of dandelion|
|Sodæ Carbonatis, ʒß.||½ drachm of sodium carbonate|
|Potasse Tartratis, ʒiij.||3 drachms of potassium tartrate|
|Tincturæ Rhei, fʒiij.||3 fluid drachms of tincture of rhubarb|
|———— Hyoscyami, gtt. xx.||20 drops of henbane tincture|
|Fiat mistura. Signa.—One third part to be taken|
three times a day. In dropsical and visceral affections.
| Make mixture. Write: "One third part to be taken|
three times a day. In dropsical and visceral affections."
|12 ounces||1 ounce||Standard|
|300 g||25 g||Venice|
|325 g||27 g||Roman Empire|
|340 g||28 g||Modern Rome|
|345 g||29 g||Iberian peninsula|
|350 g||29 g||Prussia|
|360 g||30 g||Nuremberg|
|370 g||31 g||Troy|
|420 g||35 g||Habsburg monarchy|
It is most convenient to compare the various local weight standards by the metric weights of their ounces. The actual mass of an ounce varied by ±17% (5 g) around the typical value of 30 g. The table only shows approximate values for the most important standards; even the same nominal standard could vary slightly between one city and its neighbour. The range from 25 g to 31 g is filled with numerous variants, especially the Italian range up to 28 g. But there is a relatively large gap between the troy ounces of 31 g and the Habsburg ounce of 35 g. The latter is the product of an eighteenth century weight reform.
Even in Turkey a system of weights similar to the European apothecaries' system was used for the same purpose. For medical purposes the tcheky (approx. 320 g) was divided in 100 drachms, and the drachm in (16 killos or) 64 grains. This is close to the classical Greek weight system, where a mina (corresponding roughly to a Roman libra) was also divided into 100 drachms.
With the beginning of metrication, some countries standardized their apothecaries' pound to an easily remembered multiple of the French gramme. E.g. in the Netherlands the Dutch troy pound of 369.1 g was standardized in 1820 to 375.000 g, to match a similar reform in France. 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. (At this time its use was already illegal for all purposes except trading precious metals.)
In the Romance speaking part of Europe the scruple was divided in 24 grains, in the rest of Europe in 20 grains. Notable exceptions were Venice and Sicily, where the scruple was also divided in 20 grains.
The Sicilian apothecaries' ounce was divided in 10 drachms. Since the scruple was divided in only 20 grains, like in the northern countries, an ounce consisted of 600 grains. This was not too different from the situation in most of the other mediterranean countries, where an ounce consisted of 576 grains.
In France, at some stage the apothecaries' pound of 12 ounces was replaced by the larger civil pound of 16 ounces. The subdivisions of ounces were the same as in the other Romance countries, however, and were different from the subdivisions of the civil pound.
|1 mine||16 ounces||64 shekels||128 drachms||384 scruples||768 oboli||2,304 siliquas||6,144 chalci|
|1 pound||12 ounces||48 shekels||96 drachms||288 scruples||576 oboli||1,728 siliquas||4,608 chalci|
|1 ounce||4 shekels||8 drachms||24 scruples||48 oboli||144 siliquas||384 chalci|
|1 drachm||3 scruples||6 oboli||18 siliquas||48 chalci|
|1 scruple||2 oboli||6 siliquas||16 chalci|
|436 g||327 g||27.3 g||6.82 g||3.41 g||1.14 g||568 mg||189 mg||71 mg|
Many attempts were made to reconstruct the exact mass of the Roman pound. One method for doing this consists in weighing old coins; another uses the fact that Roman weight units were derived from Roman units of length similarly to the way the litre is derived from the metre, i.e. by weighing a known volume of water. Nowadays the Roman pound is often given as 327.45 g, but one should keep in mind that (apart from the other uncertainties that come with such a reconstruction) the Roman weight standard is unlikely to have remained constant to such a precision over the centuries, and that the provinces often had somewhat inexact copies of the standard. The weight and subdivision of the pound in the Holy Roman Empire was reformed by Charlemagne, but in the Byzantine Empire it remained essentially the same. Since Byzantine coins circulated up to Scandinavia, the old Roman standard continued to be influential through the Middle Ages.
|1 Lb.||12 Unc.||108 Dr.||324 Scr.||6480 Gr.|
|1 Unc.||9 Dr.||27 Scr.||540 Gr.|
|1 Dr.||3 Scr.||60 Gr.|
|1 Scr.||20 Gr.|
|360 g||30 g||3.3 g||1.1 g||56 mg|
According to "De ponderibus et mensuris" a famous 13th century text that exists in numerous variations and is often ascribed to Dino di Garbo, the system of weights used in Salerno was different from those used in Padua and Bologna. As can be seen from the table, it was also different from the Roman weight system used by Galenus and Dioscorides and from all modern apothecaries' systems: The ounce was divided into 9 drachms, rather than 8 drachms.
Centuries later, the region around Salerno was the only exception to the rule that the apothecaries' ounce was subdivided down to the scruple in exactly the same way as in the Roman system: It divided the ounce into 10 drachms.
|1 pound||1 ounce||state or city|
|301.2 g||25.1 g||Venice|
| 320.8 g|| 26.7 g|| Kingdom of the Two Sicilies|
|325.7 g||27.1 g||Bologna|
|326.8 g||27.2 g||Milan (–1815)|
|328.0 g||27.3 g||Parma|
|332.0 g||27.7 g||Sardinia|
|334.5 g||27.9 g||Duchy of Lucca (1815–1847)|
|339.2 g||28.3 g||Rome|
|339.5 g||28.3 g||Florence|
|339.5 g||28.3 g|| Grand Duchy of Tuscany|
|340.5 g||28.4 g|| Duchy of Modena|
|344.2 g||28.7 g||Kingdom of Portugal|
| 344.8 g|
| 28.7 g|
| Kingdom of Spain|
The civil weight systems were generally very similar to the apothecaries' system, and since the libbra (or the libbra sottile, where different systems were in use for light and heavy goods) generally had a suitable weight for an apothecaries' pound it was often used for this purpose. Extreme cases were Rome and Genoa, where the same system was used for everything, including medicine. On the other hand there were relatively large differences even between two cities in the same state. E.g. Bologna (in the Papal States) had an apothecaries' pound that was less than the local civil pound, and 4% lighter than the pound used in Rome.
The weight of an apothecaries' pound ranged generally between 300 g and 320 g, slightly less than that of a pound in the Roman Empire. An important exception to this rule is that the Kingdom of Lombardy–Venetia was under rule of the Habsburg monarchy 1814–1859 and therefore had the extremely large Habsburg apothecaries' pound of 420 g. (See below under The Habsburg standard.) E.g. in the large city of Milan the apothecaries' system based on a pound of 326.8 g was officially replaced by the metric system as early as 1803, because Milan was part of the Napoleonic Italian Republic. Since the successor of this little state, the Napoleonic Kingdom of Italy, fell to Habsburg in 1814 (at a time when even in France the système usuel had been introduced because the metric system was not accepted by the population), an apothecaries' system was officially introduced again, but now based on the Habsburg apothecaries' pound, which weighed almost 30% more.
|1 Lb.||12 Unc.||120 Dr.||360 Scr.||7,200 Gr.|
|1 Unc.||10 Dr.||30 Scr.||600 Gr.|
|1 Dr.||3 Scr.||60 Gr.|
|1 Scr.||20 Gr.|
|360 g||30 g||3 g||1 g||50 mg|
The measure and weight systems for the large mainland part of the Kingdom of the Two Sicilies were unified in 1840. The area consisted of the southern half of the Italian Peninsula and included Naples and Salerno. The subdivision of apothecaries' weight in the unified system was essentially the same as that for gold, silver, coins and silk. It was the most excentric variant in that the ounce was divided in 10 drachms, rather than the usual 8. The scruple, like in Venice but unlike in the rest of the Romance region, was divided into 20 grains. The existence of a unit called aureo, the equivalent of 1½ dramme, is interesting because 6 aurei were 9 dramme. In the original Salerno weight system an ounce was divided into 9 drachms, and so an aureo would have been ⅙ of an ounce.
|1 Lb.||16 Unc.||128 Dr.||384 Scr.||9,216 Gr.|
|1 Unc.||8 Dr.||24 Scr.||576 Gr.|
|1 Dr.||3 Scr.||72 Gr.|
|1 Scr.||24 Gr.|
|480 g||30 g||4 g||1.3 g||50 mg|
The national French standard until 1799 was based on a famous artefact called the Pile de Charlemagne, which probably dates back to the second half of the 15th century. It is an elaborate set of nesting weight pieces, with a total metric weight of 12.238 kg. The set is now shown in the Musée des Arts et Métiers in Paris. The total nominal value of the set is 50 marcs de Troyes or marcs de Paris, a mark being 8 ounces. The ounce poids de marc had therefore a metric equivalent of 30.59 g. The poids de marc was used as a national French standard for trading, for gold, silver and jewels, and for weighing medicine. It was also used in international communications between scientists. In the time before the French Revolution, the civil pound also played the role of the apothecaries' pound in the French apothecaries' system, which otherwise remained a standard system of the Romance (24 grains per scruple) type.
|1 ounce||Standard||12 ounces|
|?||marc de Troyes (Troyes)||?|
|30.60 g||poids de marc (Paris)||367 g|
|30.76 g||trooisch pond (Flanders)||369 g|
|31.10 g||troy pound (London)||373 g|
In 1414, six years before the Treaty of Troyes, a statute of Henry V of England gave directions to the goldsmiths in terms of the troy pound. (In 1304 it had apparently not yet been introduced, since it did not appear in the statute of weights and measures.) There is evidence from the 15th century that the troy pound was used for weighing metals and spices. After the abolishment of the Tower pound in 1527 by Henry VIII of England, the troy pound was the official basis for English coin weights. 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.
Since the modern (English, American and Imperial) troy ounces are roughly 1.5% heavier than the late Paris ounce, the exact historical relations between the original marc de Troyes, the French poids de marc, the Flemish trooisch pond and the English troy pound are unclear. It is known, however, that the relation between the English and French troy ounces was exactly 64:63 in the fourteenth century.
|1 ounce||Standard||1 pound|
|29.69 g||Sweden||356.2 g|
|29.82 g||Nuremberg||357.8 g|
|29.83 g||Lucerne||358.0 g|
|29.88 g||Poland||358.5 g|
As of 1800 all German states and cities except Lübeck (which had the Dutch troy standard) followed the Nuremberg standard. It was also the standard for Denmark, Norway, the Russian Empire and most cantons of Switzerland. Poland and Sweden had their own variants of the standard, which differed from each other by 0.6%.
In 1811, Bavaria legally defined the apothecaries' pound as 360.00 g (an ounce of 30.00 g). In 1815, Nuremberg lost its status as a free city and became part of Bavaria. From now on the Nuremberg apothecaries' pound was no longer the official apothecaries' pound in Nuremberg; but the difference was only 0.6%. In 1836 the Greek apothecaries' pound was officially defined by this standard, four years after Otto, the son of the king of Bavaria, became the first king of Greece. But only few German states followed the example of Bavaria, and with a long delay.
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, would diverge in the opposite direction with a reform in 1816. But in both cases apothecaries continued to use the Nuremberg standard unofficially for a long time after it became illegal.
Empress Maria Theresia of Austria reformed the measures and weights of the Habsburg monarchy in 1761. The weight of an apothecaries' pound of 12 ounces was increased to a value that was later (after the kilogram was defined) found to be 420.009 g; this was called the libra medicinalis major. It was defined as 3/4 of the unusually heavy heavy Habsburg civil pound (defined as 6/5 of the civil pound of Cologne) and corresponded to a record ounce weight of 35 g.
Before the reform, in the north of the empire the Nuremberg standard had been in effect, and in Italy the local standards had been even lighter. It is not surprising that an increase by 17% and more met with some inertia. 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. In 1774, the Pharmacopoea Austriaco-provincialis used the new standard, and in 1783 all old apothecaries' weights that were still in use were directed to be destroyed.
Venice was not part of these reforms and kept its standard of approximately 25 g per ounce.
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.
|Libra||489.506 g||500.00 g|
|Uncia||30.594 g||32.00 g|| |
|Drachma||3.824 g||4.00 g|| |
|Grana||0.053 g||50 mg|| |
The Netherlands were partially metricated when they were French, in the years 1810–1813. With full metrication, effective January 1821, the Netherlands reformed the trooisch pond. The apothecaries' new pound was 375.00 g. Apart from rounding issues, this corresponded exactly to the French système usuel. (The reform was not followed in the north German city of Lübeck, which continued to use the trooisch pond.) In Belgium, apothecaries' weight was metricized effective 1856.
Between 1803 and 1815 all German regions west of the River Rhine were French, organised in the départements Roer, Sarre, Rhin-et-Moselle, and Mont-Tonnerre. As a result of the Congress of Vienna these became part of various German states. 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.
|1 ounce||Standard||1 pound|
|29.82 g||Nuremberg (initially)||357.8 g|
|29.23 g||civil pound (from 1816)||350.8 g|
|31.25 g||metric pound (from 1856)||375.0 g|
|abolished||metric pound (from 1867)||abolished|
Another reform in 1856 increased the civil pound from 467.711 g to 500.000 g (the German civil pound defined by the Zollverein), as a first step towards metrication. As a consequence the official apothecaries' pound was now 375.000 g, i.e. it was increased by 7%, and it was now very close to the troy standards. §4 of the law that introduced this reform said: "Further, a pharmaceutical weight deviating from the civil weight does not take place." But this paragraph was suspended until further notice.
The abolishment of the apothecaries' system meant that doctors' prescriptions had to take place in terms of the current civil weight: grammes and kilograms. This was considered unfeasible by many, and the state received numerous protests and asked for expertises. Yet by 1868, §4 of the earlier reform was finally put into force.
|1 Lb.||16 Unc.||128 Dr.||384 Scr.||7,000.00 Gr.|
|1 Unc.||8 Dr.||24 Scr.||437.50 Gr.|
|1 Dr.||3 Scr.||54.68 Gr.|
|1 Scr.||18.22 Gr.|
|480 g||30 g||4 g||1.3 g||70 mg|
To unify all weight systems used by apothecaries, the Irish pharmacopœia of 1850 introduced a new variant of the apothecaries' system which subdivided a new apothecaries' pound of 12 avoirdupois ounces instead of the troy pound. To allow effective use of the new system, new weight pieces were produced. Since an avoirdupois ounce corresponds to 28.35 g, the proposed system was very similar to that in use in Portugal and Spain, and in some locations in Italy. But it would have doubled the value of the avoirdupois drachm (an existing unit, but by then only used for weighing silk). Therefore it conflicted with other non-standard variations that were based on that nearly obsolete unit.
The Irish proposal was not widely adopted, but British legislation, in the form of the Medicinals Act 1858, was more radical: It prescribed the use of the avoirdupois system for the United Kingdom (then including Ireland), with none of the traditional subdivisions. This innovation was first used in the united British pharmacopœia of 1864. In practice the old apothecaries' system based on the troy pound was still widely used, however, until it was abolished by the Weights and Measures Act of 1976. Since then it can only be used to measure precious metals and stones. (The troy pound was already declared illegal for most other uses by the Weights and Measures Act of 1878.)
In the US, the metric system replaced the apothecaries' system in the US Pharmacopoeia of 1971.