.....We do not find the name “troy weight” being used before about 1390.  In my opinion the name was most likely inspired by Geoffrey of Monmouth’s Historia Regum Britanniae (c. 1136), it being popularly assumed in accordance with that account to be the weight standard brought to England from Troy by Brutus, in very ancient times.  Although fanciful in its details, the gist of this idea seems to me to be correct.  Sterling weight is a simple mathematical derivative of troy weight, and the idea that sterling (‘esterling’) weight was also brought to England from the east is found as early as 1300 in the writings of Walter de Pinchebek

.....However, it was not until the Oxford astronomer John Greaves visited Egypt around 1640 that hard evidence began to appear that certain English and Egyptian weight standards were near identical.  On his return to England Greaves published his findings concerning Roman and Greek weight standards, but kept silent about the links he had discovered to Islam.  Perhaps he feared that contemporary pre-conceived prejudices, in favour of classical precedents, would leave his audience unreceptive to his discovery.

.....Thus it was not until 1727 that Arbuthnot, having read Greaves’ travel diaries, published the discovery.  Arbuthnot was convinced by Greaves’ finding that troy weight had been brought to England from Egypt, and hypothesised that Edward I had found it there during the 9th crusade.  Arbuthnot had a first rate mind (gaining his doctorate in medicine in one day!) and was the first to write a book on mathematical probability in English.  A friend of Swift, he inspired the writing of parts of 'Gulliver’s Travels' and invented the character of John Bull, a satire on petty nationalism.  He viewed mathematics as a method of freeing the mind from superstition.

.....Arbuthnot’s book on weight standards sold well, so it is very difficult to understand why, about a century later, Ruding shows no sign of ever having opened a copy of it.  Ruding, writing in 1840, chose to believe that Norman coin weight standards were derived seamlessly from those of the Anglo-Saxons – chiefly by ignoring the actual weights of most Anglo Saxon coins.  He postulated that the Saxons already had a coinage before they ever arrived in England, on no basis whatsoever, and deduced thereby that troy weight was got from some Germanic Saxon heritage.

.....It is today possible to find evidence tending to support Ruding’s conclusion.  We now know that the weights of both the Early Anglo-Saxons and the Vikings seems to favour units that sometimes look a lot like troy pennies, or ounces.  And, as Ruding points out, a common Saxon heritage is one way to explain the very close similarity between the medieval coining standards of Cologne and London.  But Ruding’s deplorable modus operandi was to fix upon a preferred conclusion – that troy was Anglo-Saxon in origin - and then to invent evidence that supported that view; and ignore the evidence that contradicted it, from Greaves, via Arbuthnot.

.....Later in the 19th century we find an American writer who thought it very obvious that troy weight had Islamic origins:  Alexander del Mar.  However, del Mar was a renegade on this and many other matters.  He was director of the U.S. Bureau of Statistics 1866-69, but was sacked from the post, apparently for holding anti bullionist monetary views.  The poet Ezra Pound took up his cause on monetary matters, becoming in this connection the only person to be tried for treason in the USA after WWII.  Long after the death of del Mar, most economists seem to agree that he correctly anticipated Keynes concerning certain aspects of monetary theory.

.....English authors after Ruding, with one notable exception, ignored Arbuthnot and oscillated between a Germanic and a Classical explanation of the origin of troy weight.  Ridgeway concocted a rather complicated way of constructing troy out of classical Roman precedents, which seems to me only likely to convince someone who was already pre-disposed  to seek a classical precedent.  Nevertheless Connor adopted Ridgeway’s solution, rejecting the “Arabic” option without discussion.  Meanwhile Grierson championed Ruding’s Germanic solution, ignoring the fact that Greaves’ observations of Egyptian weight standards had by now been entirely corroborated, and in part by accepting a false account of the weight of the dirhem as being 2.97g, which is clearly contradicted by the coinage.

.....F G Skinner was the solitary exception to this trend.  Skinner had an engineering degree, and rose to deputy keeper of the Science Museum prior to his death in 1966.  He tested early post reform dirhems and correctly determined that they weighed 2.92 grams, whist Miles had incorrectly determined they weighed 2.95g and Grierson had taken on trust that they weighed 2.97g.  He re-examined Egyptian glass weights, and showed that the system that Greaves found in place in the 17th century AD had already been in use in the 8th century AD, results that were later corroborated by Morton.

.....Thus Skinner resurrected and extending the findings of Arbuthnot.  His results were published in a widely distributed HMSO booklet, but were almost universally ignored.  They were dismissed by Connor, and ignored by other students of the troy/tower system, Lyon, Nightingale and Mayhew.

.....After corresponding widely for five years, following leads from academic papers, from internet groups and from web sites, I have only come across one other person who, having read Skinner, understands the elegant way his theory and the evidence dovetail together.

Rob Tye