The steam-carriage shortly became the talk of the town, and the public curiosity being on the increase, Trevithick resolved on inclosing a piece of ground on the site of the present Euston station of the London and Northwestern Railway, and admitting persons to see the exhibition of his engine at so much a head. He had a tram-road laid down in an elliptical form within the inclosure, and the carriage was run round it on the rails in the sight of a great number of spectators. On the second day another crowd collected to see the exhibition, but, for what reason is not known, although it is said to have been through one of Trevithick's freaks of temper, the place was closed and the engine removed. It is, however, not improbable that the inventor had come to the conclusion that the state of the roads at that time was such as to preclude its coming into general use for purposes of ordinary traffic.
While the steam-carriage was being exhibited, a gentleman was laying heavy wagers as to the weight which could be hauled by a single horse on the Wandsworth and Croydon iron tram-way; and the number and weight of wagons drawn by the horse were something surprising. Trevithick very probably put the two things together--the steam-horse and the iron-way--and kept the performance in mind when he proceeded to construct his second or railway locomotive. In the mean time, having dismantled his steam-carriage, sent back the phaeton to the coach-builder to whom it belonged, and sold the little engine which had worked the machine, he returned to Camborne to carry on his business. In the course of the year 1803 he went to Pen-y-darran, in South Wales, to erect a forge engine for the iron-works there; and, when it was finished, he began the erection of a railway locomotive--the first ever constructed. There were already, as above stated, several lines of rail laid down in the district for the accommodation of the coal and iron works. That between Merthyr Tydvil and Cardiff was the longest and most important, and it had been at work for some years. It had probably occurred to Trevithick that here was a fine opportunity for putting to practical test the powers of the locomotive, and he proceeded to construct one accordingly in the workshops at Pen-y-darran.