This article looks at the first report of the Commissioners appointed early in the nineteenth century to consider weights and measures. It gives examples of the reasons why the Commission was appointed, comments on some of its recommendations, and then speculates on an alternative outcome had the Commission taken a different view.
The year 1819 is notable for the Peterloo Massacre, which took place on 16 August at St Peter’s Field, Manchester, when cavalry charged into a crowd of 60,000 to 80,000 who had gathered to demand the reform of parliamentary representation.
But 1819 was also the year when the Commissioners appointed to consider Weights and Measures published their first report. This report has largely been forgotten, unlike the events at St Peter’s Field which were recently the subject of a film by Mike Leigh, but it would have far-reaching consequences.
The Commission was appointed following a report in 1816 on weights and measures by a select committee of Parliament. This committee appears to have been influenced by the reform of weights and measures in France for it said:
“It appears to your committee, that the great causes of the inaccuracies which have prevailed, are the want of a fixed standard in nature, with which the standards of measure might at all times be easily compared, the want of a simple mode of connecting the measures of length, with those of capacity and weight, and also the want of proper tables of equalization, by means of which the old measures might have readily been converted into the new standards.”
In its first report, the Commission listed many of the causes of confusion which prevailed at the time, for example:
“A barrel of beer, in London, contains, by a Statute of Charles II, 36 ale gallons, a barrel of ale 32; but out of London, a barrel both of ale and beer was directed to contain 34 gallons, by a Statute of William and Mary. The distinction has been abolished by a late Act, which directs that all barrels, both of ale and beer, in town and in the country, shall contain 36 ale gallons. A barrel of herrings contains 32 gallons; of salmon, 42. Barrels and casks of fish, beef, and pork, are to be gaged (sic) by wine measure. A barrel of gunpowder is to contain 100 pounds neat.”
“Among the derivative Measures we may notice the Water Measure of fruit, which is simply a heaped bushel; and the coal bushel, which contains a Winchester Bushel and a quart of water, the coals being also heaped in the form of a cone. But all contracts for coals above five chaldrons, in London and Westminster, are to be understood as relating to Pool measure, with an ingrain of one chaldron in twenty, “according to the ancient custom of the port”. The heap must be at least six inches in height, and its base 19 1/2 in diameter.”
The Commission was assisted in its deliberations by the medical doctor and polymath Thomas Young, whose eponymous modulus of elasticity is familiar to students of physics and engineering. It also appears to have been impressed by the metric system’s link between weight (or mass) and volume, and this resulted in the following recommendation:
“7. we venture strongly to recommend, that the Standard Ale and Corn Gallon should contain exactly 10 pounds avoirdupois of distilled water, at 62º of Fahrenheit, being nearly equal to 277.2 cubic inches.”
This recommendation, when adopted, would result in the divergence between the colonial measures for volume used in the United States of America and those of the UK.
But it was the Commission’s first three recommendations that condemned the UK to the measurement muddle we face today:
“1. Upon a deliberate consideration of the whole of the system at present existing, we are impressed with a sense of the great difficulty of effecting any radical changes, to so considerable an extent, as might in some respects be desirable; and we therefore wish to proceed with great caution in the suggestions which we shall venture to propose.
2. With respect to the actual magnitude of the standards of length, it does not appear to us, that there can be any sufficient reason for altering those, which are at present generally employed.
3. The subdivisions of Weights and Measures, at present employed in this Country, appear to be far more convenient for practical purposes than the Decimal Scale.”
The report led to the Weights & Measures Act of 1824, which, though applying only to the United Kingdom of Great Britain and Ireland, led to a single system of measurement being adopted for most purposes throughout the British Empire, a system that survived, like the Empire, until the second half of the twentieth century.
It is interesting to speculate on the outcome had the Commission recommended radical reform, namely the adoption by the UK of the metric system. By 1819, the Low Countries (now The Netherlands, Luxembourg and Belgium) having been forced to use the metric system during a period of French occupation, were reluctant to give up its benefits, and went on to formally adopt it in 1820. Had the UK followed their lead, it is likely that metric measures would have been in general use within 50 years in the British Empire. Regardless of the situation in Britain, France had re-adopted the metric system in 1840, and its use spread throughout the French Empire in the second half of the nineteenth century. Portugal and Spain followed, together with the newly-independent countries of their former empires in Central and South America. As a result, the legalization of the metric system in the USA in 1866 might have been followed by its use by America’s growing manufacturing industry seeking export markets, resulting in its general adoption throughout the Americas, North, Central and South. By the beginning of the 20th century, the ‘metred globe’* could have become a reality.
It was not to be. The opportunity was lost.
The reform of parliamentary representation demanded by those gathering at St Peter’s Field on 16 August 1819 took place just 15 years later. Problems resulting from the UK’s measurement muddle, some of which the Commissioners had attempted to resolve, continue to this day.
* The title of the final chapter of “The measure of all things”, a history of the metric system by Ken Alder, published in 2002.