Sir Isaac Lowthian Bell, 1st Baronet, FRS (18 February 1816 – 20 December 1904) was a British ironmaster and Liberal Party politician from Washington, County Durham.

He was a wealthy patron of the arts, commissioning the architect Philip Webb, the designer William Morris and the painter Edward Burne-Jones on his Yorkshire mansions Rounton Grange and Mount Grace Priory.

[5][6] Bell's industrial life was complex: involvement in up to three different partnerships at the same time created a conflict of loyalties, causing allegiances to each to vary over the years.

[7] His partners and co-founders of the Washington chemical company, named after his home, were his brother-in-law Robert Benson Bowman and his father-in-law Hugh Lee Pattinson.

In September 1849 he wrote to Losh and Wilson informing them that the partnership with Pattinson "would necessitate my relinquishing the office I at present hold in your firm".

[10] Establishing a partnership with Robert Stirling Newall in 1850, Bell set up the first factory in the world with machines able to manufacture steel rope and submarine cable.

Nor is this all, for the nature of that compound which hitherto has constituted the most important application of this metal — aluminium-bronze — is so completely changed by using aluminium containing the impurities referred to [silica, iron, or phosphorus] that it ceases to possess any of those properties which render it valuable.In 1863, Bell exhibited "several pounds" of the recently discovered element thallium when the British Association met in Newcastle that autumn.

The metal was obtained from the flue deposits (mainly lead sulphate) from the manufacture of sulphuric acid from pyrites, one of the products of the Washington works.

All the credit was given to researcher Henri Brivet, who was "chief" of the laboratories at Washington, having experienced "languor and headache" then known to be caused by breathing thallium fumes.

In 1901, at age 85, after a long period of difficulty for heavy industry and with fears of worse to come as manufacturing grew in Germany, America and Japan, he made a decisive move to guard the family's wealth.

in Harley Street, London was the Head of the Household, recording Bell's occupation as "Magistrate, Deputy Lieutenant, Iron Master".

In his Iron Trade, he correctly predicted the outstripping of Britain by Germany in industrial production, unsuccessfully urging government action to avoid this.

Howell notes that the coachman could simply have had a heart attack, and not have died of exposure at all, but still, in her view "consideration for others was not, perhaps, Lowthian's principal quality".

The house was five storeys high, of yellow brick with a pantiled roof, enormous mock mediaeval chimneys and "gothic" features.

Inside was an immense arched gallery that stretched the full width of the house, a wide curved staircase and baronial fireplace.

There was a large tapestry frieze of Chaucer's Romaunt of the Rose designed by William Morris and Edward Burne-Jones, and made by Lady Bell and her daughters over several years.

[39] Given his huge wealth, Margaret and he lived relatively simply,[4][38] preferring the relatively humble[16] Arts and Crafts style for his three-year refurbishment of the medieval Mount Grace Priory near Osmotherley, which was in serious disrepair when he purchased it in 1898[40] as a weekend retreat.

[41] The house was decorated by the best designers of the day in the "Aesthetic" style, with William Morris's "Double Bough" wallpaper hand-printed using 22 apple wood printing blocks.

She observes that he was noted also for his wealth and for the innovations he made, such as the use of steel-making slag as phosphate fertilizer,[a] and that he was arguably Britain's "foremost industrialist".