|Potato field after harvest in the South Hams - Derek Harper [CC-BY-SA-2.0 (www.creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons|
Take a freshly dug early grown kidney potato, wash it free from soil, and ask a member of the opposite sex to yourself, to place it unobserved in a pocket of one of your garments. Having once worn the tuber you can change it yourself into another pocket at will, but it must be worn continuously, not intermittently, or its charm will be lost. It is believed that as the potato hardens the rheumatism will leave the system. A common practice among agricultural labourers, is to carry one in every waistcoat pocket until its looks like a small grey stone, and has become quite as hard."