asked the Secretary of State for the Environment what study he had made of apparatus for injecting steam into car petrol, which smooths the combustion process and enable engines to run on lower octane fuels; and what estimate he has made of carbon monoxide and nitrogen oxide in exhaust gases.

Independent tests have been arranged.

If this has a future, can it expect any financial advantages in the fight against pollution?

Before I answer that question I should like to see the results of the tests, but the hon. Gentleman can be assured that this project is being taken seriously.