Sir - As chairman of the Oxfordshire Yeomanry Trust, I find myself unable to refrain from pointing out an error in Mr Koenig's article about the Otmoor riot of 1830 (Weekend, September 7).

In our Regimental history there is a detailed account of the incident described, which makes it quite clear that the military involved were the Oxford Yeomanry, then known as the 1st Oxfordshire Regiment.

Under its commander, Lord Churchill, the Regiment was called out on the 5th of September, 1830, to keep order, and was reinforced on the 6th by five Troops of the Mid-Bucks Yeomanry with two field-guns.

After the Riot Act had been read, the rioters did not disperse and 57 of them were taken into custody and escorted to Oxford by 27 Yeomen.

For whatever reason, someone chose to take a route through St Giles Fair (I suspect they had forgotten about the fair) with the result that the procession was attacked by the crowd and the prisoners released to avoid bloodshed.

The Yeomanry were used for the same purpose, twice in 1831 and twice again in 1832. There is no mention in our history of the use of the Militia in aid of the civil power and it is my understanding that the conscripts in the Militia were considered to identify too closely with the people they might be required to control to be useful for this purpose.

One of the reasons for the formation of the totally volunteer Yeomanry was that they were intended to be reliable to use in keeping-the-peace within Britain (an intention, as we know, not always realised). The episode is hardly a major credit in our Regimental history, but it is an interesting reflection of the social background of the era in which it occurred.

Tim May, Chairman, Oxfordshire Yeomanry Trust