Vivian supplied the pecuniary means and joined him in the project, for which, on its completion, a patent was taken out in 1802, and in the same year a small one was erected at Marazion, which was worked by steam of at least thirty pounds on the square inch above atmospheric pressure.[40] Their steam-carriage presented the appearance of an ordinary stage-coach on four wheels, having one horizontal cylinder, which, together with the boiler and fire-box, were placed at the back of the hind axle. Mr. Michael Williams, late M.P. for Cornwall, in a letter to Mr. E. Watkins, dated the 5th of January, 1853, mentions having been present at the first trial of Trevithick's locomotive, and says "the experiments made on the public road close by Camborne were perfectly successful, and although many improvements in the details of such description of engines have been since effected, the leading principles of construction and arrangement are continued, I believe, with little alteration in the magnificent railroad engines of the present day." After making several satisfactory trials in the neighbourhood of Plymouth, Trevithick and Vivian exhibited their invention publicly in London, first at Lord's Cricket-ground, and afterwards on the spot of ground now occupied by Euston Square.[41] At this latter place, however, Trevithick, influenced by some curious whim, suddenly closed the exhibition on the second day, leaving hundreds waiting outside in a state of great wrath. Mrs. Humblestone, an old inhabitant of London, who at that period used to keep a shop near to the present Pantheon, Oxford Street, relates that she well remembers witnessing a public trial of Trevithick's steam-carriage. On this occasion the shops were shut, no horses or carriages were allowed in the streets, and the roofs of the houses in the neighbourhood were crowded with people, who hurraed and waived their handkerchiefs as the 'steam monster' was seen coming along Oxford Street at a rapid pace.[42]