Of bolls and charities:
the tangled history of Scottish
weights and measures

R.D. Connor and A.D.C. Simpson, edited by A. Morrison-Low, Weights and Measures in Scotland: A European Perspective (Edinburgh: National Museums of Scotland and Tuckwell Press, 2004), 842pp, ISBN 1 901663 88 4, £50

 Review by Julian Holland

Reproduced from The Australian Metrologist, No. 35, July 2005, pp. 15-19.

Australia’s metrological history is relatively short and straightforward.  It can be accounted for in three phases, each derived from an external source.  The first European settlers brought with them the muddled and unsatisfactory system prevailing in England in the late eighteenth century.  This was superseded from the 1830s by the Imperial System introduced by an Act of the British Parliament in 1824.  This simplified framework of measurement was a great improvement on its predecessor and lasted for a century and a half before the introduction of the metric system in the 1970s brought Australia into conformity with the majority of commercial and scientific practice in the world.

Trying to trace the metrological history of a much older nation presents greater difficulties.  Measurement practice predates written and material records.  In the case of Scotland, the task is to make sense of the fragmentary evidence and find an underlying logic to the metrological complexity which existed in the centuries before the Imperial System was promulgated in Britain in the 1820s.

Robin Connor and Allen Simpson have devoted many years to the careful analysis of the evidence to produce this major study of metrological history with a relevance reaching well beyond Scotland.  Connor has previously published the standard account of The Weights and Measures of England (1987).

Scotland’s use of weights and measures did not develop in isolation.  The early history of measurement relates particularly to trade and taxes.  Complexities arise where existing local practices are joined by measurement units governed by dominant trading partners.  Scotland had important trading links with England from an early date, but was also connected with Continental trade networks, particularly through the sale of wool to Flanders.

The evidence is such that it is not possible to give a simple account of what standards of measures were used when in Scotland.  Analysis and inference is required to find logical connections between the various standards apparently operating over time.  The evidence consists of two kinds, the legislative record and surviving physical embodiments of measurement.  Revisions were given to standard measures in various assizes over the centuries from the high middle ages.  The interpretation of these is by no means straightforward.

The earliest framework of measurement was given in the David’s Assize supposedly dating from the time of King David I who came to the throne in 1124.  Brought up in England, David reformed much legislation on the English pattern.  But the manuscript records which attribute laws to David I date from the following century and so may incorporate many silent amendments.  This may not seem to matter for so early a period but in fact this remains a problem for interpreting later legislation.

Very little from the Scottish parliamentary record survives from before the early fifteenth century, with the record of acts being fairly complete and continuous from 1466.  Scottish parliamentary acts were first produced in printed form in 1566, and several times subsequently, most comprehensively in the ‘Record Edition’ in the nineteenth century.  The early collations of the acts were not produced as authentic historical documents but as a statement of the range of law as it was then operating.  This presents problems of interpreting the metrological force of successive assizes in their own time.

The other principal source of evidence is the array of surviving physical artifacts of metrology.  The physical evidence provides a valuable check on the legislative history.  One of the most fascinating aspects of this study is the variety of ways in which a unit can vary depending on the context.

I am old enough to remember feet and inches, pounds and ounces, and so on, in daily use:  sixteen ounces in a pound, fourteen pounds in a stone.  Well, this was the tidied up arrangement in the Imperial system, and these were avoirdupois pounds.  But there were also troy weights.  Going back in time one finds there were parallel units depending on the commodity: ale gallons were not the same as wine gallons, and these could each vary over time.

There were several reasons why a given unit could vary, even for a particular commodity.  A legal unit of volume could be defined in several ways.  Firstly, it could be determined by the mass of its contents or its dimensional volume.  The mass of the contents could be defined by water, either ‘diuers watters’ – a mixture of fresh and sea water – or fresh water of the river Tay.  So long as a consistent type of water was used, determination by mass or linear dimension should give consistent results.  This is fine for liquid measures but cannot be translated to the hierarchy of dry measures.

There is an apparent inconsistency in the definitions of the pint (dry measure) and the wheat firlot (the forth part of a boll) in the 1618 Assize.  The firlot was a cylindrical vessel 19 1/16 inches diameter and 7 1/3 inches deep.  Its capacity was 21 ¼ fills of the pint.  These do not represent the same volume (if tested by liquid measure).  The firlot contains 2110 cubic inches while 21 ¼ pints represents 2205 cubic inches.  However, taking into account the physical characteristics of the material being measured (small seeds with rough surfaces), the shape of the vessels the seeds are poured into, the manner of pouring and the resultant stacking pattern, it turns out by experiment that the seeds are more tightly packed by about 4 ½ percent when poured into a broad vessel than into a narrow one.  So, in fact, for measuring wheat, the firlot does represent 21 ¼ fills of the pint.

This is only one example of the need to understand the relation between the legal basis of metrology and the reality of commercial practice.  The legal units were not necessarily given a physical embodiment because a system of allowances and ‘charities’ was applied in commercial practice which meant that an extra quantity was included in the transaction, often one sixteenth.  In the case of ‘water measures’ this was usually one eighth.  These were not liquid quantities but goods transported by sea.  These various allowances for bulk goods protected the recipient against loss due to retail subdivision or spoilage in transport.  Clearly it also favoured the buyer and landlords receiving feudal dues in kind.  Connor and Simpson have carefully analysed the record of assizes and surviving early measures to show how the application of allowances seems to have driven a cycle of expansion of the dimensions of actual measures which were then incorporated into successive legal measures.

Weights and Measures in Scotland is a detailed and meticulous study which seeks to show an underlying logic to the development of Scotland’s legal metrology.  It is divided into three parts, the main text, an inventory of surviving standards, and a series of appendices.  The inventory is an impressive collation of information with 261 entries covering individual items or groups of related items.  These are discussed in detail and many are illustrated.  Given that metrological legislation often sought to eliminate irregular or outdated measures, it is remarkable that such a large quantity of physical evidence remains, although some have been modified over time.  The unique Inverkeithing firlot gauge dating from 1500 seems to have survived despite successive enlargements of the firlot due to its also being a gauge for the Scottish ell (37 inches) – see Figures 1 and 2.

Figure 1.  Inverkeithing firlot gauge and ell bed made in 1500.  This detail shows the inscription giving the name of William Carmichael and the date.  In 1500 Carmichael was the Treasurer of the burgh of Edinburgh and his name thus indicates the authority of the gauge.  No other such gauge is known. This one seems to have survived the successive increases in the firlot because of its dual use as a bed for testing ells, which remained 37 inches.  (Item 1 in the Inventory)
(Reproduced courtesy of the National Museums of Scotland, Edinburgh)

Figure 2.  Diagram showing the use of the Inverkeithing gauge to check the depth and diameter of a firlot measure.
(Reproduced courtesy of the National Museums of Scotland, Edinburgh)

Careful measurements of a number the early weights and measures underpin the close and intricate arguments of Part I.  Just as the reader of a Russian novel needs a card of dramatis personae to keep track of the various characters’ names, so the various relationships of weights particularly require the reader to maintain at least a mental tabulation.  We find stones with varying numbers of pounds, and pounds with varying numbers of ounces.  And the ounces themselves are defined by a number of grains – which were slightly different from the grains used in recent centuries!  This particularly applies to troy weights.

Troy weights have a very long history in relation to the trade in fine goods such as precious metals and spices.  These were the sort of goods transported over long distances and worth weighing very accurately.  Such trading means that measurement systems stretch beyond the local market.  Troy weights derive their name from the French town of Troyes where seasonal trading fairs were held in the high middle ages, bringing together traders from the Low Countries to the north and Italy to the south.

Variants of the troy ounce affected Scotland from several trading relationships, so at different times the relevant ounce means a different quantity, given in grains:  471 (bullion), 472½ (Paris), ~474.5 (Flemish), 476.8 (Dutch or Amsterdam), 480 (English troy).  The original Scottish ounce was 450 grains and was equivalent to the Cologne or English ‘tower’ ounce.  This indicates the close relationship between weight systems and the minting of coinage.  There is also a definable relationship between several of the ounces, showing that they do not merely represent arbitrary changes due to poor metrological precision.  For example, the Cologne and Paris ounces are in the ratio 20:21.  As a peripheral contributor to the European economy, Scotland was influenced by the usages of its major trading partners as well as the state of its political relations with England.

The nine chapters of the principal text are largely concerned with understanding the legal changes to Scottish metrology between the David Assize of the twelfth century and the Assize of 1618, the last Scottish framework of measurement, and how these were applied in practice with allowances.  The Act of Union with England in 1707 meant that English weights and measures were intended to be adopted.  In fact Scottish practice continued to a considerable extent, and even with the introduction of the Imperial System in the 1820s, existing measures continued to be used for some time.

The appendices provide the main Scottish metrological acts, considerations of regional variants and special usages, including land measure and the assizes of bread and ale, a glossary of measures, and a directory of Scottish scale, weight and measure makers to 1900.

In addition to the points already discussed it is full of interesting insights into the history of measurement.  For example, weighing was not always undertaken with a horizontal beam.  Inclined-beam weighing seems to have been widespread for bulk goods in European markets in the later middle ages.  This produced a slight excess over the nominal weight by four percent.  This was known as a cloffe allowance as a benefit to the purchaser or alternatively as a tare allowance to take account of the packaging material containing the bulk goods.

And in the eighteenth century the quest for numerical precision led to inappropriately precise measurements of surviving early standards with some spurious interpretations.  For example, the length of standard bed measures - with a recessed portion representing the length of the 37-inch ell - was taken literally, but this gave rise to the idea of oversized Scots inches because of a failure to make allowance for a tolerance for placing scales in the bed.  Another variant ell of 37.2 inches, which emerged from the cloth trade in about 1700, apparently demonstrated to later observers that the Scots inch (at 37 to the ell) was even longer. Although this ell became widely used, it had been applied out of context, and the English and Scots inches were actually identical.

Both these examples indicate the caution required in the use of historical evidence.

Weights and Measures in Scotland is thoroughly referenced and profusely illustrated.  This very substantial book provides a careful and detailed analysis of the fragmentary evidence of the legal basis of weights and measures in Scotland since the middle ages and its relationship with trade practice.  In doing so it sheds new light on the history of English metrology and indeed the relations of Scottish and English metrology with Continental practice.

Figure 3.  Set of troy nesting weights, 1687.  This set of cup weights makes up a pile of 512 bullion ounces and illustrates the principal of binary division.  While the metric system with its decimal divisions superseded the old fashioned units of weights and measures, the spread of digital computing has made such binary multiples familiar once again.  The two innermost weights, each of 2 ounces, are missing.  (Item 41 in the Inventory)
(Reproduced courtesy of the National Museums of Scotland, Edinburgh)