 His background in engineering was put to good use on a number of projects . In particular , the John Martins store on Rundle Street ( now Rundle Mall ) , was constructed by raising the top floor of the building on hydraulic jacks , building two new floors underneath while the remainder of the store continued to operate normally . Another of Laybourne Smith 's buildings , the Australian Mutual Provident building on King William Street in Adelaide , was one of the first in the state to feature air conditioning , as this was considered to be quite an " innovative " addition in 1934 . 
