Joe,
You are correct as usual. We know that the rolling mills did not come to Belgium in a "big way" until the 1830's. By 1856 Higny had produced a sheet with 20 different patterns. There were patents being filed in the 1890's for various patterns in Belgium. Also, the rolling mills themselves were under going change. I have seen engravings of the early mills that were hand operated. By about 1880 this had changed.
It is one of the difficulties of the research. A description from 1910 simply may not apply to the process in 1810 or even 1880.
Pete
