I consider it somewhat facile of my hon. Friend the Member for Maidstone (Mr. John Wells) to dismiss those who are genuinely worried about the project as "bogus opponents", as I think he did. I try to be constructive; nevertheless I find the Bill controversial and I therefore cannot agree as much as I would have liked with all that my hon. Friend the Member for Edinburgh, North (Mr. Alexander Fletcher) said. I very much enjoyed listening to his speech, however, and I join with those on both sides of the House who have congratulated him on it.

The right hon. Member for Sheffield, Park (Mr. Mulley) said that we on this side of the House were complacent. That surprised me because I sat through the Committee and remaining stages of the initial finance Bill and the hon. Member for Ashton-under-Lyne (Mr. Sheldon) battled in splendid isolation on the Opposition side. He did not even have the support of his own front bench. The Opposition benches were completely deserted except for him. That showed a remarkable lack of concern about the whole project.

Since we last debated the matter two events of significance, already mentioned in the debate, have occurred. One is the oil situation, which is becoming more serious, and the other is the prospect of a lower rate of economic growth. These are complex questions, as my hon. Friend the Under-Secretary said in opening the debate, and they require further examination. As he also indicated, traffic predictions affecting the profitability of the tunnel are based on forecasts that take neither of these factors into account.

In spite of what my hon. Friend the Member for Folkestone and Hythe (Mr. Costain) said, I firmly believe that holi-daymakers touring Europe in their cars, from whom over 50 per cent. of the tunnel revenue is expected to accrue, constitute the type of traffic which is most vulnerable of all to petrol restrictions and economic recession. In view of the outlook for the economy and for petrol supplies, and in view of the recent welcome shift of emphasis by the Government from road to rail what becomes all-important is whether in passing the Bill we commit ourselves to the shuttle-ferry tunnel. It is not clear from Clause 2 which defines the tunnel system, whether the Bill, coupled with Article 3 of the treaty, commits us to a specific design of tunnel. I would very much welcome elucidation from the Minister on that point. Article 3 refers to the design of railway installations and fixed and movable railway equipment, including ferry wagons. It says that these matters are still to be settled between the companies, the railways and the Governments. It goes on to say that the matter is still open and in default of an agreement the final decision is to be made by the Governments.

I hope that the passage of the Bill will not settle the matter and that it is possible under its provisions for the conventional Berne gauge system to be substituted for the rolling shuttle-ferry service. The sponsors of the project have estimated that this would save 30 per cent. of the expected construction costs—some £300 million. My hon. Friend the Under-Secretary no doubt knows of the French kangaroo system, which is, I believe, the equivalent of our freightliner service, and which is capable of taking all road traffic, including heavy lorries, on the Berne gauge system. Does my hon. Friend also know of the system operated by the German Federal Railways? My hon and learned Friend the Member for Dover (Mr. Peter Rees) asked earlier what were the alternatives, and I have no doubt—