From Probus the line would now run to the northern margin of Truro and then south to Falmouth. This avoided the crossing of the Truro River and the objectionable crossing at Penryn. By now the shortcomings in the atmospheric system were becoming apparent, and nothing more was heard of that system for the Cornwall Railway. Although the magnitude of the Tamar crossing was daunting, Brunel was persuasive in giving evidence supporting it. In fact the Bill admitted the possibility of using the Hamoaze ferry but Parliament mandated the bridge Detail of how the bridge at Saltash was to be made was vague at this stage, and it may be that Brunel's powers of persuasion deflected detailed examination of this. The line was to be . The authorised share capital was £1,600,000 with borrowing powers of £533,333, and the Associated Companies (the GWR, the B&ER and the SDR as a bloc) were authorised to subscribe. There were to be branches to Padstow, to the Liskeard and Caradon Railway, and to the quays at Truro and Penryn, and the Company was authorised to purchase the Bodmin and Wadebridge Railway, the Liskeard and Caradon Railway and the Liskeard and Looe Union Canal. (None of the branches and purchases were activated in the form envisaged in the Act.) The line was to be of the same track gauge as the GWR. The scheme obtained the Royal Assent on 3 August 1846. Work starts At this time the general financial depression following the railway mania had set in, and apart from a small amount of work near St Austell, little progress in constructing the line was made, except for an investigation of the river bed for the Saltash crossing; this was completed by March 1848. The railway mania was a phenomenon in which a huge number of railway schemes were put forward, when investors imagined that huge gains on investment were certain. Investors overcommitted themselves, and many lost substantial sums; money became scarce even for respectable schemes as subscribers simply had no money to pay calls on their shares. At the same time labour and material prices escalated substantially. At a meeting in February 1851, Brunel informed the directors that if the scheme were reduced to a single line, the whole route could be constructed for £800,000, including the Tamar crossing and all stations. In April 1852 the directors proposed a capital reconstruction that reduced