At the time of Federation, standard gauge was used in only NSW, but was favoured for further work. Work on gauge conversion was assisted by section 51 (xxxiii) of the Constitution of Australia, which made specific provisions for the Commonwealth Parliament to make laws with respect to railway acquisition and construction. An agreement was made with the South Australian and Western Australian state governments for the Trans-Australian Railway from Port Augusta to Kalgoorlie, with work started in 1911 and completed in 1917. However, with the different gauges, to ship goods from Queensland to Perth required four transhipments.