In the 1839 Wrightson's Directory they seem to have combined with another :
Barron and Mills, brass founders, and manufacturers of improved brass rods, gauze wire and transparent window blinds; also factors and merchants,
25, Lower Temple-street, and 72 and 73, Wells-st. Oxford-st. London.
They are not listed in Pigots 1841 directory
By 1839 they are described (see attached , at
https://books.google.co.uk/books?id=AkEFimYNoxgC&pg=PA270&lpg=PA270&dq="Barron+and+Mills"&source=bl&ots=kQAUIPyxsf&sig=ACfU3U0wbS5E_QgE7f7oFCWRKeUjzchAnA&hl=en&sa=X&ved=2ahUKEwib5JmC8dbnAhUIQEEAHZXPCeQQ6AEwAnoECAgQAQ#v=onepage&q="Barron and Mills"&f=false)
as "of London", so maybe the firm moved to London
From:
https://s3.amazonaws.com/hpef-digit...+Rehab+Guide-2-History+and+Technology-ocr.pdf :
The spring roller was a recent advance, and because of its extra cost,Loudon felt it suitable for villas only.12 It wasstill so novel in 1844 that Webster and Parkes felt the need to define it for readers:
Spring roller blinds have a wire spring inside a tin roller, which acts so as to tum it, and the blind is raised up by merely pulling a cord: these are much more expensive than the common rollerblind, which has the advantage of greater simplicity, and being less apt to be out of order. 13
According to Loudon, the best spring rollers were made by Barron and Mills.