In this work he was associated with notable engineers of the eighteenth century, such as John Smeaton, James Brindley and Abraham Darby and his clients included dukes and earls as well as lesser gentry.
Brown was responsible for the introduction of larger iron cylinders, eventually as large as 75 inches in size (and 10 feet long) compared to the 42 inch cylinders in use in 1750, which made more powerful engines possible.