Joseph Campbell was both an Anglican clergyman and a scientist, with a preference for the latter. Actively involved in educating the masses in scientific matters, and particularly those, like miners, with particular problems to overcome, he was a rather shameless self-publicist, insisting that he could solve most things. Sometimes he was correct, and his practical advice was valued, especially in the last phase of his life. After Alfred Andrew Lockwood developed a method of treating refractory Te Aroha ore, Campbell modified it, naming it the thermo-hyperphoric process. After inspecting Hauraki mines in 1896, he later settled at Te Aroha to test his process on a large scale. Great success was promised, with claims being made that he could save most of the assay value of the ore in a process superior to any other. Other miners along with geologists were critical of his claims and of his understanding of the geology, but he ignored them. The Montezuma Company was formed in London to fund the development of mines mostly between Tui and Te Aroha, and to erect his plant. Despite his promises, his plant failed, to great local disappointment. In addition to trialing ore treatment, Campbell also experimented in other areas. After leaving Te Aroha and focusing for a time on being a clergyman, he settled in North Queensland, remaining there until his death trying to solve a variety of problems facing primary producers, sometimes with success. To the end of his life he claimed to be an expert in a myriad of fields, and ignored all his critics.