The scale of charges is very low.  The cost of sending a letter from Peking to Hankow—­650 miles, as the crow flies—­being no more than eight cents, or four pence.  About thirty per cent. of the postage is always paid by the sender, to secure the office against imposition and loss; the balance is recoverable from the person to whom the letter is addressed.  These offices are largely used by merchants in the course of trade, and bills of exchange are constantly being thus sent, while the banks forward the foil or other half to the house on which it is drawn, receipt of which is necessary before the draft can be cashed.  Such documents, together with small packets of sycee, make up a tolerably valuable bag, and would often fall a prey to the highwaymen which infest many of the provinces, but that most offices anticipate these casualties by compounding for a certain annual sum which is paid regularly to the leader of the gang.  For this blackmail the robbers of the district not only agree to abstain from pilfering themselves, but also to keep all others from doing so too.  The arrangement suits the local officials admirably, as they escape those pains and penalties which would be exacted if it came to be known that their rule was too weak, and their example powerless to keep the district free from the outrages of thieves and highwaymen.  Large firms, which supply carts to travellers between given points, are also often in the habit of contracting with the brigands of the neighbourhood for the safe passage of their customers.  In some parts soldiers are told off by the resident military officials to escort travellers who leave the inns before daybreak, until there is enough light to secure them against the dangers of a sudden attack.  In others, there are bands of trained men who hire themselves out in companies of three to five to convey a string of carts with their dozen passengers across some dangerous part of the country, where it is known that foot-pads are on the look-out for unwary travellers.  The escort consists of this small number only, for the reason that each man composing it is supposed to be equal to five or six robbers, not in mere strength, but in agility and knowledge of sword-exercise.  To accustom themselves to the attacks of numbers, and to acquire the requisite skill in fighting more than one adversary at a time, these men practise in the following remarkable manner.  In a lofty barn heavy bags of sand are hung in a circle by long ropes to the roof, and in the middle of these the student takes up his position.  He then strikes one of the bags a good blow with his fist, sending it flying to a distance from him, another in the same way, then another, and so on until he has them all swinging about in every possible direction.  By the time he has hit two or three it is time to look out for the return of the first, and sometimes two will come down on him at once from opposite quarters; his part is to be ready for all emergencies, and keep the whole lot swinging without ever letting one touch him.  If he fails in this, he must not aspire to escort a traveller over a lonesome plain; and, besides, the ruthless sand-bag will knock him head over heels into the bargain.