Here’s more from History of Negros (1980):
The coming of these new hacenderos brought about improvements in the technology of sugar cane cultivation as well as in that of the manufacture of sugar.
The newcomers began by replacing the old molave mills by modern iron mills. The metal cylinders crushed the cane better and thus extracted more juice.
According to Loney the difference came to 30% in favor of iron mills. In 1857 there was only one iron mill in Negros. On July 1861, thirteen could be found, and Loney foresaw that they would double by the end of that year.
In 1861 the first steam mill was installed with its own evaporating tubs and steam turbines the better to separate all liquids from the crystalized sugar. It seems that the first centrifugal sugar in Negros was produced in Hacienda Constancia belonging to Agustín Montilla. The second centrifugal mill was installed by Loney himself.
The greatest improvement in the cultivation of sugar cane was the gradual replacement of the Chinese plow, which only scratched the soil by European plows with iron blades.
The first replacements were carried out by the Spaniard Mascuñana. The greater part of these plows was imported from England by Russell and Sturgis (American) and Ker and Co. (English). The first of these companies was already active in Negros in 1857, the second in 1859.
By the end of 1859 the Spanish hacendero José Alvarez y Sotomayor had already installed in Hinigaran iron mills, cauldrons and ovens bought from Ker and Co.