James Watt Steam Engine Built 1807 (litho) - description by John Steele, Jr. in 1832

Lithograph appears to be hand colored and visible matted area measures approx 42cm wide x 60cm high.

James Watt was a Scottish inventor, mechanical engineer, and chemist who improved on Thomas Newcomen's 1712 Newcomen steam engine with his Watt steam engine in 1776, which was fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world.
While working as an instrument maker at the University of Glasgow, Watt became interested in the technology of steam engines. He realised that contemporary engine designs wasted a great deal of energy by repeatedly cooling and reheating the cylinder. Watt introduced a design enhancement, the separate condenser, which avoided this waste of energy and radically improved the power, efficiency, and cost-effectiveness of steam engines. Eventually he adapted his engine to produce rotary motion, greatly broadening its use beyond pumping water.
Watt attempted to commercialise his invention, but experienced great financial difficulties until he entered a partnership with Matthew Boulton in 1775. The new firm of Boulton and Watt was eventually highly successful and Watt became a wealthy man. In his retirement, Watt continued to develop new inventions though none was as significant as his steam engine work.
He developed the concept of horsepower  and the SI unit of power, the watt, was named after him. (source: Wikipedia)

John Steele Jr. (Junr appears to be a British abbreviation for Junior) has added a very detailed description to this lithograph, with measurements and data, signed and dated by him on May 3, 1832. John Steele Jr.'s relationship with James Watt is unknown and merits further research. Was John Steele Jr. also a Scottish engineer who knew James Watt? If the written description is accurate, the steam engine was built 12 years before James Watt died. This was well towards the end of Watt's career.   No other copy of this lithograph has been able to be located.