Marcus, being offline with hard drive failure, asked me to post something about this to see if anyone has further info about the subject.
Marcus tells me that Richard "Beau" Nash, born 1674, and well known as a dandy/leader of fashion & society in 18th century Bath, was the "son of a glassmaker." A book published in 2005, called
The Imaginary Autocrat: Beau Nash and the Invention of Georgian Bath by John Eglin, gives slightly more info about the enterprise: Richard Nash, senior, was the namesake father to Beau Nash, and he was a partner in a "glass bottle making concern" which produced "a thousand quart-bottles a week." Nash's partner in the business was John Man, and their glassworks was in Swansea in the former seat of the Duke of Beaufort. Richard Nash, snr, sold his stake in the glassworks in 1692 when his son left Oxford.
[Source:
Amazon.co.uk listing for
The Imaginary Autocrat: Beau Nash and the Invention of Georgian Bath by John Eglin]
Swansea Heritage Net website adds a little more to the story, in saying that by 1678 a glassworks in Swansea "was established by Robert Wilmott of Gloucester and John Man of Swansea." "Wilmott leased space in the castle, from the Duke of Beaufort, for seven years from 1684. Although work must have begun earlier because the words 'glass house' appear on a sketch of the castle by Francis Place in 1678. Wilmott sold the lease to his partner in 1686. Very high tax was imposed on glass-making in 1695 and although it only lasted for two years it may have been enough to close John Man's glassworks in 1696."
By 1696 it was "one of 37 across England & Wales" existing at that time. [Source: Swansea Heritage Net website
http://www.swanseaheritage.net/article/gat.asp?ARTICLE_ID=510]
If anyone happens across more info about this glassworks could you please add it to this topic for reference. Many thanks.

Edited to add, it would be an interesting exercise to identify all the 37 glassworks existing in 1696 in England and Wales.