sˌʌm klˈuː æz tə ðə sˈaɪz ʌvðə tɹˈeɪnz kæn biː əbtˈeɪnd fɹʌmðə stˈʌdi kˈæɹid ˈaʊt fɹʌmðə fɹˈɛntʃ ɡˈʌvɚnmənt ɪn wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd fˈoːɹɾi θɹˈiː ɐ tɹˈeɪn ʌv θˈɜːɾi ˈeɪt tˈʌnz ɡɹˈoʊs wˈeɪt wʌz dᵻskɹˈaɪbd wˌɪtʃ kəmpɹˈaɪzd sˈɛvən kˈæɹɪdʒᵻz ænd kˈæɹid tˈuːhˈʌndɹɪd pˈiːpəl, ænd ɪn sˈʌbsᵻkwənt tˈɛsts tɹˈeɪn wˈeɪts ʌv ˌʌp tə sˈɛvənti tˈʌnz ɑːɹ ɹᵻpˈoːɹɾᵻd.
Some clue as to the size of the trains can be obtained from the study carried out from the French Government in 1843 A train of 38 tons gross weight was described which comprised 7 carriages and carried 200 people, and in subsequent tests train weights of up to 70 tons are reported.