[Pg 219][1] We have but little record of anything which could be called "assaying" among the Greeks and Romans. The fact, however, that they made constant use of the touchstone (see note 37, p. 252) is sufficient proof that they were able to test the purity of gold and silver. The description of the touchstone by Theophrastus contains several references to "trial" by fire (see note 37, p. 252). They were adepts at metal working, and were therefore familiar with melting metals on a small scale, with the smelting of silver, lead, copper, and tin ores (see note 1, p. 353) and with the parting of silver and lead by cupellation. Consequently, it would not require much of an imaginative flight to conclude that there existed some system of tests of ore and metal values by fire. Apart from the statement of Theophrastus referred to, the first references made to anything which might fill the rôle of assaying are from the Alchemists, particularly Geber (prior to 1300), for they describe methods of solution, precipitation, distillation, fusing in crucibles, cupellation, and of the parting of gold and silver by acid and by sulphur, antimony, or cementation. However, they were not bent on [Pg 220]determining quantitative values, which is the fundamental object of the assayer's art, and all their discussion is shrouded in an obscure cloak of gibberish and attempted mysticism. Nevertheless, therein lies the foundation of many cardinal assay methods, and even of chemistry itself.

The first explicit records of assaying are the anonymous booklets published in German early in the 16th Century under the title Probierbüchlein. Therein the art is disclosed well advanced toward maturity, so far as concerns gold and silver, with some notes on lead and copper. We refer the reader to Appendix B for fuller discussion of these books, but we may repeat here that they are a collection of disconnected recipes lacking in arrangement, the items often repeated, and all apparently the inheritance of wisdom passed from father to son over many generations. It is obviously intended as a sort of reminder to those already skilled in the art, and would be hopeless to a novice. Apart from some notes in Biringuccio (Book III, Chaps. 1 and 2) on assaying gold and silver, there is nothing else prior to De Re Metallica. Agricola was familiar with these works and includes their material in this chapter. The very great advance which his account represents can only be appreciated by comparison, but the exhaustive publication of other works is foreign to the purpose of these notes. Agricola introduces system into the arrangement of his materials, describes implements, and gives a hundred details which are wholly omitted from the previous works, all in a manner which would enable a beginner to learn the art. Furthermore, the assaying of lead, copper, tin, quicksilver, iron, and bismuth, is almost wholly new, together with the whole of the argument and explanations. We would call the attention of students of the history of chemistry to the general oversight of these early 16th Century attempts at analytical chemistry, for in them lie the foundations of that science. The statement sometimes made that Agricola was the first assayer, is false if for no other reason than that science does not develop with such strides at any one human hand. He can, however, fairly be accounted as the author of the first proper text-book upon assaying. Those familiar with the art will be astonished at the small progress made since his time, for in his pages appear most of the reagents and most of the critical operations in the dry analyses of gold, silver, lead, copper, tin, bismuth, quicksilver, and iron of to-day. Further, there will be recognised many of the "kinks" of the art used even yet, such as the method of granulation, duplicate assays, the "assay ton" method of weights, the use of test lead, the introduction of charges in leaf lead, and even the use of beer instead of water to damp bone-ash.

The following table is given of the substances mentioned requiring some comment, and the terms adopted in this book, with notes for convenience in reference. The German terms are either from Agricola's Glossary of De Re Metallica, his Interpretatio, or the German Translation. We have retained the original German spelling. The fifth column refers to the page where more ample notes are given:—

[Pg 224][2] Crudorum,—unbaked?

[3] This reference is not very clear. Apparently the names refer to the German terms probier ofen and windt ofen.

[Pg 226][4] Circulus. This term does not offer a very satisfactory equivalent, as such a furnace has no distinctive name in English. It is obviously a sort of forge for fusing in crucibles.

[Pg 230][5] Spissa,—"Dry." This term is used in contra-distinction to pingue, unctuous or "fatty."

[Pg 232][6] Additamenta,—"Additions." Hence the play on words.

We have adopted "flux" because the old English equivalent for all these materials was "flux," although in modern nomenclature the term is generally restricted to those substances which, by chemical combination in the furnace, lower the melting point of some of the charge. The "additions" of Agricola, therefore, include reducing, oxidizing, sulphurizing, desulphurizing, and collecting agents as well as fluxes. A critical examination of the fluxes mentioned in the next four pages gives point to the Author's assertion that "some are of a very complicated nature." However, anyone of experience with home-taught assayers has come in contact with equally extraordinary combinations. The four orders of "additions" enumerated are quite impossible to reconcile from a modern metallurgical point of view.

[7] Minium secundarium. (Interpretatio,—menning. Pb₃O₄). Agricola derived his Latin term from Pliny. There is great confusion in the ancient writers on the use of the word minium, for prior to the Middle Ages it was usually applied to vermilion derived from cinnabar. Vermilion was much adulterated with red-lead, even in Roman times, and finally in later centuries the name came to be appropriated to the lead product. Theophrastus (103) mentions a substitute for vermilion, but, in spite of commentators, there is no evidence that it was red-lead. The first to describe the manufacture of real red-lead was apparently Vitruvius (VII, 12), who calls it sandaraca (this name was usually applied to red arsenical sulphide), and says: "White-lead is heated in a furnace and by the force of the fire becomes red lead. This invention was the result of observation in the case of an accidental fire, and by the process a much better material is obtained than from the mines." He describes minium as the product from cinnabar. Dioscorides (V, 63), after discussing white-lead, says it may be burned until it becomes the colour of sandaracha, and is called sandyx. He also states (V, 69) that those are deceived who consider cinnabar to be the same as minium, for minium is made in Spain out of stone mixed with silver sands. Therefore he is not in agreement with Vitruvius and Pliny on the use of the term. Pliny (XXXIII, 40) says: "These barren stones (apparently lead ores barren of silver) may be recognised by their colour; it is only in the furnace that they turn red. After being roasted it is pulverized and is minium secundarium. It is known to few and is very inferior to the natural kind made from those sands we have mentioned (cinnabar). It is with this that the genuine minium is adulterated in the works of the Company." This proprietary company who held a monopoly of the Spanish quicksilver mines, "had many methods of adulterating it (minium)—a source of great plunder to the Company." Pliny also describes the making of red lead from white.

[8] Ochra plumbaria. (Interpretatio,—pleigeel; modern German,—Bleigelb). The German term indicates that this "Lead Ochre," a form of PbO, is what in the English trade is known as massicot, or masticot. This material can be a partial product from almost any cupellation where oxidation takes place below the melting point of the oxide. It may have been known to the Ancients among the various species into which they divided [Pg 233]litharge, but there is no valid reason for assigning to it any special one of their terms, so far as we can see.

[9] There are four forms of copper named as re-agents by Agricola:

The first of these was no doubt finely divided copper metal; the second, third, and fourth were probably all cupric oxide. According to Agricola (De Nat. Fos., p. 352), the scales were the result of hammering the metal; the flowers came off the metal when hot bars were quenched in water, and a third kind were obtained from calcining the metal. "Both flowers (flos) and hammer-scales (squama) have the same properties as crematum copper.... The particles of flower copper are finer than scales or crematum copper." If we assume that the verb uro used in De Re Metallica is of the same import as cremo in the De Natura Fossilium, we can accept this material as being merely cupric oxide, but the aes ustum of Pliny—Agricola's usual source of technical nomenclature—is probably an artificial sulphide. Dioscorides (V, 47), who is apparently the source of Pliny's information, says:—"Of chalcos cecaumenos, the best is red, and pulverized resembles the colour of cinnabar; if it turns black, it is over-burnt. It is made from broken ship nails put into a rough earthen pot, with alternate layers of equal parts of sulphur and salt. The opening should be smeared with potter's clay and the pot put in the furnace until it is thoroughly heated," etc. Pliny (XXXIV, 23) states: "Moreover Cyprian copper is roasted in crude earthen pots with an equal amount of sulphur; the apertures of the pots are well luted, and they are kept in the furnace until the pot is thoroughly heated. Some add salt, others use alumen instead of sulphur, others add nothing, but only sprinkle it with vinegar."

[10] The reader is referred to note 6, p. 558, for more ample discussion of the alkalis. Agricola gives in this chapter four substances of that character:

Soda (nitrum). Lye. "Ashes which wool-dyers use." "Salt made from the ashes of musk ivy."

The last three are certainly potash, probably impure. While the first might be either potash or soda, the fact that the last three are mentioned separately, together with other evidence, convinces us that by the first is intended the nitrum so generally imported into Europe from Egypt during the Middle Ages. This imported salt was certainly the natural bicarbonate, and we have, therefore, used the term "soda."

[11] In this chapter are mentioned seven kinds of common salt:

And in addition sal tostus and sal torrefactus. Sal facticius is used in distinction from rock-salt. The melted salt would apparently be salt-glass. What form the sal tostus and sal torrefactus could have we cannot say, however, but they were possibly some form of heated salt; they may have been combinations after the order of sal artificiosus (see p. 236).

[12] "Stones which easily melt in hot furnaces and sand which is made from them" (lapides qui in ardentibus fornacibus facile liquescunt arenae ab eis resolutae). These were probably quartz in this instance, although fluorspar is also included in this same genus. For fuller discussion see note on p. 380.

[13] Tophus. (Interpretatio, Toffstein oder topstein). According to Dana (Syst. of Min., p. 678), the German topfstein was English potstone or soapstone, a magnesian silicate. It is scarcely possible, however, that this is what Agricola meant by this term, for such a substance would be highly infusible. Agricola has a good deal to say about this mineral in De Natura Fossilium (p. 189 and 313), and from these descriptions it would seem to be a tufaceous limestone of various sorts, embracing some marls, stalagmites, calcareous sinter, etc. He states: "Generally fire does not melt it, but makes it harder and breaks it into powder. Tophus is said to be a stone found in caverns, made from the dripping of stone juice solidified by cold ... sometimes it is found containing many shells, and likewise the impressions of alder leaves; our people make lime by burning it." Pliny, upon whom Agricola depends largely for his nomenclature, mentions such a substance (XXXVI, 48): "Among the multitude of stones there is tophus. It is unsuitable for [Pg 234]buildings, because it is perishable and soft. Still, however, there are some places which have no other, as Carthage, in Africa. It is eaten away by the emanations from the sea, crumbled to dust by the wind, and washed away by the rain." In fact, tophus was a wide genus among the older mineralogists, Wallerius (Meditationes Physico-Chemicae De Origine Mundi, Stockholm, 1776, p. 186), for instance, gives 22 varieties. For the purposes for which it is used we believe it was always limestone of some form.

[14] Saxum fissile album. (The Interpretatio gives the German as schifer). Agricola mentions it in Bermannus (459), in De Natura Fossilium (p. 319), but nothing definite can be derived from these references. It appears to us from its use to have been either a quartzite or a fissile limestone.

[15] Argol (Feces vini siccae,—"Dried lees of wine." Germ. trans. gives die wein heffen, although the usual German term of the period was weinstein). The lees of wine were the crude tartar or argols of commerce and modern assayers. The argols of white wine are white, while they are red from red wine. The white argol which Agricola so often specifies would have no special excellence, unless it may be that it is less easily adulterated. Agricola (De Nat. Fos., p. 344) uses the expression "Fex vini sicca called tartarum"—one of the earliest appearances of the latter term in this connection. The use of argol is very old, for Dioscorides (1st Century A.D.) not only describes argol, but also its reduction to impure potash. He says (V, 90): "The lees (tryx) are to be selected from old Italian wine; if not, from other similar wine. Lees of vinegar are much stronger. They are carefully dried and then burnt. There are some who burn them in a new earthen pot on a large fire until they are thoroughly incinerated. Others place a quantity of the lees on live coals and pursue the same method. The test as to whether it is completely burned, is that it becomes white or blue, and seems to burn the tongue when touched. The method of burning lees of vinegar is the same.... It should be used fresh, as it quickly grows stale; it should be placed in a vessel in a secluded place." Pliny (XXIII, 31) says: "Following these, come the lees of these various liquids. The lees of wine (vini faecibus) are so powerful as to be fatal to persons on descending into the vats. The test for this is to let down a lamp, which, if extinguished, indicates the peril.... Their virtues are greatly increased by the action of fire." Matthioli, commenting on this passage from Dioscorides in 1565, makes the following remark (p. 1375): "The precipitate of the wine which settles in the casks of the winery forms stone-like crusts, and is called by the works-people by the name tartarum." It will be seen above that these lees were rendered stronger by the action of fire, in which case the tartar was reduced to potassium carbonate. The weinstein of the old German metallurgists was often the material lixiviated from the incinerated tartar.

Dried lees of vinegar (siccae feces aceti; Interpretatio, die heffe des essigs). This would also be crude tartar. Pliny (XXIII, 32) says: "The lees of vinegar (faex aceti); owing to the more acrid material are more aggravating in their effects.... When combined with melanthium it heals the bites of dogs and crocodiles."

[16] Dried lees of aqua which separates gold and silver. (Siccae feces aquarum quae aurum ab argento secernunt. German translation, Der scheidwasser heffe). There is no pointed description in Agricola's works, or in any other that we can find, as to what this material was. The "separating aqua" was undoubtedly nitric acid (see p. 439, Book X). There [Pg 235]are two precipitates possible, both referred to as feces,—the first, a precipitate of silver chloride from clarifying the aqua valens, and the second, the residues left in making the acid by distillation. It is difficult to believe that silver chloride was the feces referred to in the text, because such a precipitate would be obviously misleading when used as a flux through the addition of silver to the assays, too expensive, and of no merit for this purpose. Therefore one is driven to the conclusion that the feces must have been the residues left in the retorts when nitric acid was prepared. It would have been more in keeping with his usual mode of expression, however, to have referred to this material as a residuus. The materials used for making acid varied greatly, so there is no telling what such a feces contained. A list of possibilities is given in note 8, p. 443. In the main, the residue would be undigested vitriol, alum, saltpetre, salt, etc., together with potassium, iron, and alum sulphates. The Probierbüchlin (p. 27) also gives this re-agent under the term Toden kopff das ist schlam oder feces auss dem scheydwasser.

[17] Recrementum vitri. (Interpretatio, Glassgallen). Formerly, when more impure materials were employed than nowadays, the surface of the mass in the first melting of glass materials was covered with salts, mostly potassium and sodium sulphates and chlorides which escaped perfect vitrification. This "slag" or "glassgallen" of Agricola was also termed sandiver.

[18] The whole of this expression is "candidus, candido." It is by no means certain that this is tin, for usually tin is given as plumbum candidum.

[Pg 236][19] Sal artificiosus. These are a sort of stock fluxes. Such mixtures are common in all old assay books, from the Probierbüchlin to later than John Cramer in 1737 (whose Latin lectures on Assaying were published in English under the title of "Elements of the Art of Assaying Metals," London, 1741). Cramer observes (p. 51) that: "Artificers compose a great many fluxes with the above-mentioned salts and with the reductive ones; nay, some use as many different fluxes as there are different ores and metals; all which, however, we think needless to describe. It is better to have explained a few of the simpler ones, which serve for all the others, and are very easily prepared, than to tire the reader with confused compositions: and this chiefly because unskilled artificers sometimes attempt to obtain with many ingredients of the same nature heaped up beyond measure, and with much labour, though not more properly and more securely, what might have been easily effected, with one only and the same ingredient, thus increasing the number, not at all the virtue of the things employed. Nevertheless, if anyone loves variety, he may, according to the proportions and cautions above prescribed, at his will chuse among the simpler kinds such as will best suit his purpose, and compose a variety of fluxes with them."

[20] This operation apparently results in a coating to prevent the deflagration of the saltpetre—in fact, it might be permitted to translate inflammatur "deflagrate," instead of kindle.

[21] The results which would follow from the use of these "fluxes" would obviously depend upon the ore treated. They can all conceivably be successful. Of these, the first is the lead-glass of the German assayers—a flux much emphasized by all old authorities, [Pg 237]including Lohneys, Ercker and Cramner, and used even yet. The "powerful flux" would be a reducing, desulphurizing, and an acid flux. The "more powerful" would be a basic flux in which the reducing action of the argols would be largely neutralised by the nitre. The "still more powerful" would be a strongly sulphurizing basic flux, while the "most powerful" would be a still more sulphurizing flux, but it is badly mixed as to its oxidation and basic properties. (See also note 19 on sal artificiosus).

[22] Lead ash (Cinis Plumbi. Glossary, Pleyasch).—This was obviously, from the method of making, an artificial lead sulphide.

[23] Ashes of lead (Nigri plumbi cinis). This, as well as lead ash, was also an artificial lead sulphide. Such substances were highly valued by the Ancients for medicinal purposes. Dioscorides (V, 56) says: "Burned lead (Molybdos cecaumenos) is made in this way: Sprinkle sulphur over some very thinnest lead plates and put them into a new earthen pot, add other layers, putting sulphur between each layer until the pot is full; set it alight and stir the melted lead with an iron rod until it is entirely reduced to ashes and until none of the lead remains unburned. Then take it off, first stopping up your nose, because the fumes of burnt lead are very injurious. Or burn the lead filings in a pot with sulphur as aforesaid." Pliny (XXXIV., 50) gives much the same directions.

[Pg 238][24] Camphor (camphora). This was no doubt the well-known gum. Agricola, however, believed that camphor (De Nat. Fossilium, p. 224) was a species of bitumen, and he devotes considerable trouble to the refutation of the statements by the Arabic authors that it was a gum. In any event, it would be a useful reducing agent.

[25] Inasmuch as orpiment and realgar are both arsenical sulphides, the use of iron "slag," if it contains enough iron, would certainly matte the sulphur and arsenic. Sulphur and arsenic are the "juices" referred to (see note 4, p. 1). It is difficult to see the object of preserving the antimony with such a sulphurizing "addition," unless it was desired to secure a regulus of antimony alone from a given antimonial ore.

[Pg 239][26] The lead free from silver, called villacense, was probably from Bleyberg, not far from Villach in Upper Austria, this locality having been for centuries celebrated for its pure lead. These mines were worked prior to, and long after, Agricola's time.

[Pg 242][27] This method of proportionate weights for assay charges is simpler than the modern English "assay ton," both because of the use of 100 units in the standard of weight (the centumpondium), and because of the lack of complication between the Avoirdupois and Troy scales. For instance, an ore containing a libra of silver to the centumpondium would contain 1/100th part, and the same ratio would obtain, no matter what the actual weight of a centumpondium of the "lesser weight" might be. To follow the matter still further, an uncia being 1/1,200 of a centumpondium, if the ore ran one "uncia of the lesser weight" to the "centumpondium of the lesser weight," it would also run one actual uncia to the actual centumpondium; it being a matter of indifference what might be the actual weight of the centumpondium upon which the scale of lesser weights is based. In fact Agricola's statement (p. 261) indicates that it weighed an actual drachma. We have, in some places, interpolated the expressions "lesser" and "greater" weights for clarity.

This is not the first mention of this scheme of lesser weights, as it appears in the Probierbüchlein (1500? see Appendix B) and Biringuccio (1540). For a more complete discussion of weights and measures see Appendix C. For convenience, we repeat here the Roman scale, although, as will be seen in the Appendix, Agricola used the Latin terms in many places merely as nomenclature equivalents of the old German scale.

[Pg 243][28] The amalgamation of gold ores is fully discussed in note 12, p. 297.

[Pg 244][29] For discussion of the silver ores, see note 8, p. 108. Rudis silver was a fairly pure silver mineral, the various coloured silvers were partly horn-silver and partly alteration products.

[Pg 245][30] It is difficult to see why copper scales (squamae aeris—copper oxide?) are added, unless it be to collect a small ratio of copper in the ore. This additional copper is not mentioned again, however. The whole of this statement is very confused.

[Pg 247][31] This old story runs that Hiero, King of Syracuse, asked Archimedes to tell him whether a crown made for him was pure gold or whether it contained some proportion of silver. Archimedes is said to have puzzled over it until he noticed the increase in water-level upon entering his bath. Whereupon he determined the matter by immersing bars of pure gold and pure silver, and thus determining the relative specific weights. The best [Pg 248]ancient account of this affair is to be found in Vitruvius, IX, Preface. The story does not seem very probable, seeing that Theophrastus, who died the year Archimedes was born, described the touchstone in detail, and that it was of common knowledge among the Greeks before (see note 37). In any event, there is not sufficient evidence in this story on which to build the conclusion of Meyer (Hist. of Chemistry, p. 14) and others, that, inasmuch as Archimedes was unable to solve the problem until his discovery of specific weights, therefore the Ancients could not part gold and silver. The probability that he did not want to injure the King's jewellery would show sufficient reason for his not parting these metals. It seems probable that the Ancients did part gold and silver by cementation. (See note on p. 458).

[32] The Alchemists (with whose works Agricola was familiar—vide preface) were the inventors of nitric acid separation. (See note on p. 460).

[33] Parting gold and silver by nitric acid is more exhaustively discussed in Book X. and note 10, p. 443.

[34] The lesser weights, probably.

[Pg 251][35] Lead and Tin seem badly mixed in this paragraph.

[36] It is not clear what is added.

[Pg 252][37] Historical Note on Touchstone. (Coticula. Interpretatio,—Goldstein). Theophrastus is, we believe, the first to describe the touchstone, although it was generally known to the Greeks, as is evidenced by the metaphors of many of the poets,—Pindar, Theognis, Euripides, etc. The general knowledge of the constituents of alloys which is implied, raises the question as to whether the Greeks did not know a great deal more about parting metals, than has been attributed to them. Theophrastus says (78-80): "The nature of the stone which tries gold is also very wonderful, as it seems to have the same power with fire; which is also a test of that metal. Some people have for this reason questioned the truth of this power in the stone, but their doubts are ill-founded, for this trial is not of the same nature or made in the same manner as the other. The trial by fire is by the colour and by the quantity lost by it; but that by the stone is made only by rubbing the metal on it; the stone seeming to have the power to receive separately the distinct particles of different metals. It is said also that there is a much better kind of this stone now found out, than that which was formerly used; insomuch that it now serves not only for the trial of refined gold, but also of copper or silver coloured with gold; and shows how much of the adulterating matter by weight is mixed with gold; this has signs which it yields from the smallest weight of the adulterating matter, which is a grain, from thence a colybus, and thence a quadrans or semi-obolus, by which it is easy to distinguish if, and in what degree, that metal is adulterated. All these stones are found in the River Tmolus; their texture is smooth and like that of pebbles; their figure broad, not round; and their bigness twice that of the common larger sort of pebbles. In their use in the trial of metals there is a difference in power between their upper surface, which has lain toward the sun, and their under, which has been to the earth; the upper performing its office the more nicely; and this is consonant to reason, as the upper part is dryer; for the humidity of the other surface hinders its receiving so well the particles of metals; for the same reason also it does not perform its office as well in hot weather as in colder, for in the hot it emits a kind of humidity out of its substance, which runs all over it. This hinders the metalline particles from adhering perfectly, and makes mistakes in the trials. This exudation of a humid matter is also common to many other stones, among others, to those of which statues are made; and this has been looked on as peculiar to the statue." (Based on [Pg 253]Hill's trans.) This humid "exudation of fine-grained stones in summer" would not sound abnormal if it were called condensation. Pliny (XXXIII, 43) says: "The mention of gold and silver should be accompanied by that of the stone called coticula. Formerly, according to Theophrastus, it was only to be found in the river Tmolus but now found in many parts, it was found in small pieces never over four inches long by two broad. That side which lay toward the sun is better than that toward the ground. Those experienced with the coticula when they rub ore (vena) with it, can at once say how much gold it contains, how much silver or copper. This method is so accurate that they do not mistake it to a scruple." This purported use for determining values of ore is of about Pliny's average accuracy. The first detailed account of touch-needles and their manner of making, which we have been able to find, is that of the Probierbüchlein (1527? see Appendix) where many of the tables given by Agricola may be found.

[38] De Natura Fossilium (p. 267) and De Ortu et Causis Subterraneorum (p. 59). The author does not add any material mineralogical information to the quotations from Theophrastus and Pliny given above.

[39] In these tables Agricola has simply adopted Roman names as equivalents of the old German weights, but as they did not always approximate in proportions, he coined terms such as "units of 4 siliquae," etc. It might seem more desirable to have introduced the German terms into this text, but while it would apply in this instance, as we have discussed on p. 259, the actual values of the Roman weights are very different from the German, and as elsewhere in the book actual Roman weights are applied, we have considered it better to use the Latin terms consistently throughout. Further, the obsolete German would be to most readers but little improvement upon the Latin. For convenience of readers we set out the various scales as used by Agricola, together with the German:—

The term "nummus," a coin, given above and in the text, appears in the German translation as pfennig as applied to both German scales, but as they are of different values, [Pg 254]we have left Agricola's adaptation in one scale to avoid confusion. The Latin terms adopted by Agricola are given below, together with the German:—

While the proportions in a bes or mark are the same in both scales, the actual weight values are vastly different—for instance, the mark contained about 3609.6, and the bes 3297 Troy Grains. Agricola also uses:

As the Roman libra contains 12 unciae and the German pfundt 16 untzen, the actual weights of these latter quantities are still further apart—the former 4946 and the latter 7219 Troy grains.

[40] There are no tables in the Latin text, the whole having been written out in extenso, but they have now been arranged as above, as being in a much more convenient and expressive form.

[Pg 259][41] See note 39 above.

[Pg 261][42] See note 27, p. 242, for discussion of this "Assay ton" arrangement.

[Pg 263][43] Agrippinenses and Antuerpiani.