inventor of Reaction Turbine; based in Glasgow; worked in Paisley, Scotland with James Stirrat, patented an improved version of Barker’s mill in 1841 in England and 1843 in America; it became known as the Scotch turbine, and is regarded as the first true metal turbine water wheel; Whitelaw patented La Cour’s improvement of the bottom-feeding of the supply water, adding spiral curved arms decreasing in cross-section from wheel opening to jet; 1843 - American patent (#3,153) claims the proportioning of these arms as his patentable improvement; Scotch turbine was manufactured in Europe and America by a number of firms from the 1840s - early 1870s;