The life of the law has not been logic; it has been experience.

As we shall find it necessary, in our endeavours to bring electrical phenomena within the province of dynamics, to have our dynamical ideas in a state fit for direct application to physical questions we shall devote this chapter to an exposition of these dynamical ideas from a physical point of view.

But Shaanxi also commands attention from scholars of more modern times. It was into the unremarkable small market town of Yanan, a drab, inhospitable, inaccessible settlement, that in 1936 tramped a procession of weary peasant soldiers. These were troops of the Red Peasants’ and Workers’ Army, and at their head was a disgruntled intellectual named Mao Zedong. It was the end of the Long March, and it was to Yanan that Mao had led those few of his men who survived with him and tramped and fought their way across China. If Xian and other ancient capitals along the Huanghe and its tributaries are places of pilgrimage for those curious about the imperial past, then Yanan is likewise a magnet for those wishing to visit the cradle of the New China. Here, hacked into the loess cliff face, is the cave home where Mao lived for most of the eleven years that Yanan was headquarters of the communists.

The tendency in these types of situations (as far as I can see) is that because I don't think the act itself is illegal, the police will go through your vehicle systematically loking for anything wrong with it, to slap a canary on it (that's slang for an unroadworthy sticker) or present you with some other fine.