Paddington's capacity was doubled to four tracks in the 1870s. The quadrupling was completed to on 30 October 1871, in June 1879 and in September 1884. An additional platform (later to become No. 9) opened in June 1878, while two new departure platforms (later Nos. 4 and 5) were added in 1885. One of the lines between what is now platform 5 and 7 was removed, in order that the latter could be moved to a more southerly position. Aside from the June 1878 work, Brunel's original roof structure remained untouched throughout the improvements.