engine rotational speed, the engine efficiency is lowered when the engine rotates at speeds other than the particular engine rotational speed.
There has been proposed an engine whose intake and exhaust valves are opened and closed under electromagnetic forces produced by electromagnets. The timing of opening and closing the intake and exhaust valves can be varied as the rotational speed of the engine varies, so that the engine can operate with high efficiency at different rotational speeds.
In the proposed engine with the electromagnetic valve control system, the intake and exhaust valves themselves can be opened and closed under relatively small forces. When the exhaust valve is to be opened while the engine is in operation, however, a large force is required to be applied to the exhaust valve sinceof Budget Day.

Indeed, Mr Hammond may well be relieved that he does not need to deliver a Budget until the Autumn. A year ago, his first Budget was widely seen as disastrous for the Government, with the Chancellor having to quickly backtrack on heavily-criticised tax rises for the self-employed, providing helpful ammunition for the opposition at the subsequent general election.

Nevertheless, being the first of its kind, the Spring Statement was still something of an unknown quantity and the business community was still curious to see what he might have to say as they waited for the cheers and jeers to quieten in the Commons.

As it turned out, the Chancellor stuck to his guns, saying at the start of the speech that the UK had been unique amongst major