Samuel Morse received his first ever patent for the telegraph in 1847, at the old Beylerbeyi Palace (the present Beylerbeyi Palace was built in 1861–1865 on the same location) in Istanbul, which was issued by Sultan Abdülmecid who personally tested the new invention. Following this successful test, installation works of the first telegraph line (Istanbul-Adrianople–Şumnu) began on 9 August 1847. In 1855 the Ottoman telegraph network became operational and the Telegraph Administration was established. In 1871 the Ministry of Post and the Telegraph Administration were merged, becoming the Ministry of Post and Telegraph. In July 1881 the first telephone circuit in Istanbul was established between the Ministry of Post and Telegraph in the Soğukçeşme quarter and the Postahane-i Amire in the Yenicami quarter. On 23 May 1909, the first manual telephone exchange with a 50 line capacity entered service in the Büyük Postane (Grand Post Office) in Sirkeci.