them than was available locally. In 1885 several Mining Agents formed themselves into a Mining Exchange. This made speculation through the buying and selling of mine shares possible. In 1886, a display featuring ore samples from the Charters Towers mines was set up at the Colonial and Indian Exhibition in London. At the time, some mines were producing extraordinary quantities of gold. The response from British investors resulted in a speculation boom. This did not hold, collapsing in 1888, but as the fabled Brilliant Reef was discovered in the following year, the fortunes of the field were not depressed for long. The boom had encouraged a number of local businessmen to replace their timber buildings with more substantial brick structures. Alexander Malcolm, who had been on the field since the early 1870s was one of these, replacing his Malcolm's Buildings in Mosman Streets with an elegant arcade of shops and offices. The arcade was designed for him by Sydney architect Mark Cooper Day and was named the Royal Arcade. In 1890 the Stock Exchange reformed along better organised lines and looked for new premises. The Royal Arcade was a wise choice, being centrally placed in the main business area and close to agents and banks. The Exchange signed an initial three-year lease for the use of an office and the courtyard for their evening call at a rent of ten pounds a month. To begin with, two calls a day were made, one at noon and another, open to the public, in the evening. Public interest was such that this evening call was attended by crowds. In 1892 the introduction of the McArthur-Forrest cyanide process boosted gold production for the field which peaked in 1899 at . The population also peaked in this year at around 26,500. Charters Towers was now the second most important city in Queensland and an internationally noted goldfield. After 1899, the yield of Charters Towers mines gradually diminished and increasing costs, due to the great depths at which gold was being mined, saw the return to investors falling. In 1912 the Warden reported that the extreme depth for profitable mining had been reached. The population fell sharply, as many people moved to coastal towns. In 1916, with little interest in new ventures from investors, the stock exchange closed. Falling real estates values and vacant buildings allowed a number of private schools to establish themselves, providing