In 1841 John Knight II withdrew from the task and retired to Rome, and Frederick took up the task with much vigour. He built 15 further farmsteads and changed his father's policy of in-hand farming of the forest as one huge entity to one of colonising the moor with tenant farmers who would bear the risks and rewards of the farming operations themselves and would pay him rents. This was during a time of great population expansion when it was widely feared that food supplies would inevitably run short. The political situation was uncertain and revolution was feared unless the price of food could be reduced. Thomas Malthus had written in 1798: The power of population is indefinitely greater than the power in the earth to produce subsistence for man. Both father and son were unsuccessful with the mining ventures they planned on Exmoor, although much expenditure was made in prospecting for minerals and one mine-shaft was sunk, named Wheal Eliza. A large pond known as Pinkworthy Pond, was dug on The Chains, a boggy expanse of moorland in the NW corner of the forest, the purpose of which is unknown, but was possibly to drive mill machinery. Knight was a keen sportsman and also valued his Exmoor estate for the stag-hunting, which had been practised there with hounds for centuries. He also encouraged the abandonment of his father's determined policy of attempting to grow wheat, more suited to lowlands, and sought to introduce a pastoral system using sheep. He is said to have largely designed many of the farmstead lay-outs himself, and these have been found to the present day to be well sheltered and well drained. Most of Knight's farmsteads survive today, only 5 having been demolished or partly so, namely: