Francis and William Crossley bought out the engineering company of John M Dunlop in Manchester in 1867 to form Crossley Brothers. The Coptic Cross was chosen as an emblem for the company in celebration of the brothers Christianity. Crossley brothers bought rights to the Otto four stroke engine, and in 1896 the acquired rights to the Diesel engine as well. In 1901 Crossley started manufacture of petrol engines in Manchester and in 1905 Leyland lorries used these engines. To concentrate on vehicle production Crossley Motors was founded in 1906. Engine production carried on separately until the 1960s. Car production started in 1907 with some very large-engined models before designers AW Reeves and GH Woods designed a 12/14hp model in 1909 and this would become the 15hp in 1910. A 20hp 4,500cc model was introduced in 1909 and this evolved into the 20/25 which became the mainstay of Crossley production through the War years until 1926. A new 19.6hp Crossley with a 3.8-litre engine evolved into the sporting 20/70. A new 14hp (actually 15.6) was launched in 1923, and in 1925 the first Crossley Six engine was launched as the 18/50. and then upgraded to the 3.2-litre 20.9 in 1927. A smaller 1,990cc six cylinder 15.7hp car was introduced in 1928 and from this the hotter 2-litre Sports model was produced; the Lagonda 16/80 used a version of this engine. Crossley couldn't compete with other car manufacturers during the 1930s and stopped car production in 1937 in favour of othere businesses. Commercial vehicle production relied on military orders and did not restart after WWII. Crossley buses continued until they sold out to AEC in 1948 and became part of ACV (Associated Commercial Vehicles).