 By the mid @-@ 1870s the slow speed of the Aveling and Porter locomotives and their unreliability and inability to handle heavy loads were recognised as major problems for the Tramway . In 1874 Ferdinand de Rothschild bought a 2 @,@ 700 @-@ acre ( 1 @,@ 100 ha ) site near the Tramway 's Waddesdon station to use as a site for his country mansion of Waddesdon Manor . The Tramway 's management recognised that the construction works would lead to a significant increase in the haulage of heavy goods , and that the Aveling and Porter engines would be unable to cope with the increased loads . The newly established engineering firm of W. G. Bagnall wrote to the Duke offering to hire a locomotive to him for trials . The offer was accepted , and on 18 December 1876 the locomotive was delivered . The tests were generally successful and an order was placed to buy a locomotive from Bagnall for £ 640 ( about £ 54 @,@ 300 in 2016 ) which was delivered on 28 December 1877 . With trains now hauled by the Bagnall locomotive ( the Kingswood branch generally remained worked by horses , and occasionally by the Aveling and Porter engines ) , traffic levels soon rose . Milk traffic rose from 40 @,@ 000 gallons carried in 1875 to 58 @,@ 000 gallons ( 260 @,@ 000 l ; 70 @,@ 000 US gal ) in 1879 , and in 1877 the Tramway carried a total of 20 @,@ 994 tons ( 21 @,@ 331 t ) of goods . In early 1877 the Tramway was shown on Bradshaw maps for the first time , and from May 1882 Bradshaw included its timetable . 
