The cost of conveying coal from pit to staithe induced mine-owners to lay the first tramroads. The reduction in tractive effort allowed one horse to pull 42 cwt on rails instead of 17 cwt on a road and a pair of horses could haul a 50-passenger double-deck tram with no greater effort than that required for a 26-passenger omnibus. Horse power was the biggest expenditure of a tramway. 9 to 11 horses were needed for each car; 4 or 5 pairs to work in shifts, and one spare in the stables. A tram horse’s working life was only 4 or 5 years. The cost of horses rose as services expanded. The weight of cars remained around 50 cwt until 1870 when some American tramways introduced a smaller and lighter car requiring only one horse. Similar cars were introduced to Britain. The saving was so great that horse tramways became practicable in small towns and other routes. Places like Chesterfield, with a modest population, relied on the one-horse tram throughout the pre-electric era. Trams had been running in the town since 1882. The Council acquired the business in 1897 and supplemented the existing horse cars with three new single-deckers from George F. Milnes & Co Ltd. These cars ran for seven years, until electrification in 1904. A councillor discovered horse car No. 8 being used as a summer-house. It is now one of the finest horse-drawn single-deckers in existence. Presented by Chesterfield Corporation to the British Transport Commission in 1956 it can be seen today at the National Tramway Museum at Crich, Derbyshire, England.