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James Watt (Junior) (1769–1848), engineer and manufacturer
1769 February 5th. Born on at Glasgow, the son of the engineer James Watt
He was then sent off to France en route to Geneva to study the classics, history, science, mathematics, drawing, and French.
1788 Watt returned to England and joined the firm of Taylor and Maxwell, fustian manufacturers, in Manchester.
1794 Watt became increasingly useful to Boulton and Watt. With Matthew Robinson Boulton he investigated and prosecuted pirates of his father's patents, he promoted the copying machine, he introduced the principle of ‘rationalization’ into the construction of Soho foundry in 1796, he recruited founders from Wilkinson's works, and he took over the main direction of the steam-engine company.
In 1817 Watt purchased Bell's PS Caledonia and refitted her with two 14 hp Boulton and Watt engines. He then took the ship to the Netherlands and ascended the Rhine as far as Koblenz. It is claimed that this was the first steam crossing of the channel.
As a result of this and other experiments, the manufacture of marine engines increased in his firm, culminating in HMS James Watt (1853), fitted with Soho engines.
Mid 1830s James Watt (Junior) took the French Wall's Works into his own hands and ran it in conjunction with the Soho Foundry, though as a separate concern, until old age forced him to give it up in 1842 .
The French Walls works provided the Soho Foundry with boiler plates and uses (semi-finished forgings for engines) as well as turning out merchant iron and steel. Scrap from the Foundry was returned to the French Wall's for reworking .
Watt finished his days in grand style at Aston Hall, having become a pillar of society as well as something of a dandy.
1841 Living at Aston Park (age 72), Independent. 
1848 Unmarried, he died at Aston Hall, Birmingham, on 2 June 1848.
Note: 1821 Beam Engine had the following markings on its gudgeon brasses carrying the beam:- No. 416, GUDGEON BLOCKS, 40 HORSES, SIX FEET, STROKE, 1821
Also displayed a brass plate attached to the engine marked: JAMES WATT, SOHO, 1821