 sought to disprove this and make long-distance contacts. In America there were a large number of radio amateurs who were permitted to use relatively high powers, and reports of long-distance contacts soon started to appear. With this in mind, the possibility of short wave communication across the Atlantic was thought to be a possibility. The first attempts were made in December 1921, with British stations listening for their American counterparts who could use much higher powers. These first attempts proved to be unsuccessful; however, the following winter many stations were heard. Then in November 1923, the first two way contact was made between an American in Connecticut and a French station. With this barrier broken regular transatlantic commu- nications started to be made. Contacts were also made over further distances, one between London and Dunedin in New Zealand was made in October 1924. While radio amateurs took the limelight, commercial interests were also investigating the possibilities of the short wave bands. A telephone circuit was set up between Hendon in North London and Birmingham in 12 Newnes Guide to Radio and Communications Technology 1921, and later that year another was inaugurated between Southwold in Sussex and Zandvoort in Holland. Seeing the success of all these projects Marconi decided to make further investigations into the properties of these bands. He set up a 2kW transmitting station at Poldhu, the site of his long wave transmitter in 1901, and he used receivers on his yacht Elettra to monitor the transmissions. He found that signals up to St Vincent in the West Indies (a distance of 2300 miles) could be received at sufficient strength to support a telephone channel. Many other tests and experiments were performed, and slowly the short wave bands started to be used for international traffic. By the late 1920s radio was providing a valuable method of providing international telephone circuits. Links were even opened up to ocean liners to provide instant communication for passengers w