Sheng Pa slowly scratched his belly and agreed that it was not impossible that some such thing might happen.

Ma Joong detected a marked lack of enthusiasm.

He fumbled in his sleeve and extracted a piece of silver. He weighed it on the palm of his hand and let the light of the torch play on it.

'When I hid my thirty silver pieces,' he said, 'I took one along for good luck. I wonder whether you would accept it as an advance payment on the commission due to you for acting as an intermediary for the proposed deal.'

Sheng Pa snatched the coin from Ma Joong's hand with amazing agility. With a broad smile he said:

'Brother, I shall see what I can do for you. Come back tomorrow night!'

Ma Joong thanked him, and took leave of his new friends with a few pleasant words.

When he came back to the tribunal, Ma Joong quickly changed, then went to the main courtyard. He noticed that there was still a light in the judge's private office.

He found Judge Dee and Sergeant Hoong in conference.

When Judge Dee saw Ma Joong, he broke off the conversation and asked:

'Well, my friend, what is the news?'

Ma Joong reported briefly on his encounter with Sheng Pa and told the judge about the latter's promise.

Judge Dee was pleased.

'It would have been a piece of the most extraordinary good luck,' he observed, 'if you had found the criminal on the very first day. You have made an excellent start. News travels fast along certain channels in the underworld and I think you have now established contact with the right man. I have no doubt that in due time your friend Sheng Pa will give you a clue to the missing hairpins, and those will lead you to the murderer.

'Now, before you came, we were discussing the wisdom of my setting out tomorrow to pay courtesy visits to my colleagues in the neighbouring districts. Sooner or later I have to comply with the custom and the present seems an opportune time. I shall be absent from Poo-yang two or three days. In the meantime you will continue your efforts to apprehend the murderer of Half Moon Street. If you think it necessary, I shall order Chiao Tai to join in the search.'

Ma Joong thought it better if he went about it alone, since two people enquiring after the same object might arouse suspicion. The judge agreed, and Ma Joong took his leave.

'It would be very opportune,' mused Sergeant Hoong, 'if Your Honour would be absent for a day or two, and the tribunal closed. Then there would be a valid reason for letting the case against Candidate Wang rest. The rumour is spreading that Your Honour is protecting Wang because he is a member of the literary class while his victim was but a poor shopkeeper's daughter.'

Judge Dee shrugged his shoulders and said:

'Be that as it may, I shall leave for Woo-yee tomorrow morning. The following day I shall proceed directly to Chin-hwa and return here on the third day. Since Ma Joong or Tao Gan may need instructions during my absence, you had better not accompany me, Sergeant; stay here and take charge of the seals of the tribunal. You will give the necessary instructions and see that suitable courtesy presents are prepared for my colleague Pan in Woo-yee, and Judge Lo, the magistrate of Chin-hwa. Have my travelling palankeen loaded with my luggage ready in the main courtyard early in the morning!'

Sergeant Hoong assured the judge that his orders would be executed without fail. Judge Dee leaned forward in his chair to read some documents that the senior scribe had placed on the desk for his inspection.

The sergeant seemed reluctant to go and remained standing in front of Judge Dee's desk.

After a while the judge looked up and asked:

'What is on your mind, Sergeant?'

'Your Honour, I have been thinking about that rape-murder, I have read and reread the records. But try as I may I cannot follow your reasoning. The hour is late but if before leaving tomorrow Your Honour would favour me with some further explanation, I will at least be able to sleep during the two nights that Your Honour will be away!'

Judge Dee smiled and placed a paper-weight on the document on his desk. Then he settled back into his arm-chair.

'Sergeant,' he said, 'order the servants to bring a pot of fresh tea and then sit down on the tabouret here. I shall explain to you what I think actually happened on the fateful night of the sixteenth.'

When he had drunk a cup of strong tea, Judge Dee began:

'As soon as I had heard from you the main facts of this case, I ruled out Candidate Wang as the man who raped Pure Jade. It is true that woman may sometimes raise in man strange and cruel thoughts; it is not without reason indeed that in his Annals of Spring and Autumn our Master Confucius on occasion refers to woman as "that fey creature "

'There are but two classes of people, however, who translate such dark thoughts into deeds. First, the low-class, utterly depraved habitual criminals. Second, rich lechers who through long years of debauch have become the slaves of their perverted instincts. Now I could possibly imagine that even a studious young man of sober habits like Candidate Wang, if he were in a frenzy of fear, would strangle a girl. But as to his raping her, what is more a girl with whom he had had intimate relations for more than six months, this seemed to me absolutely impossible. So I had to find the real criminal among the members of the two classes I referred to just now.

'I immediately discarded the possibility of a wealthy degenerate. Such persons frequent secret haunts where all vice and perversion can be indulged in if one is prepared to pay in gold. A wealthy man would probably not even be aware of the existence of a quarter of poor shopkeepers such as Half Moon Street. It is most unlikely that he would have had an opportunity to learn about Wang's visits, to say nothing of his ability to perform acrobatics at the end of a strip of cloth! Thus there remained the low-class, habitual criminal.'

Here the judge paused a moment. Then he continued in a bitter voice:

'Those despicable ruffians roam all through the town like hungry dogs. If in a dark alley they happen to meet a defenceless old man they knock him down and rob him of the few strings of copper cash he carries. If they see a woman walking alone they beat her unconscious and then rape her, tear the rings from her ears, and leave her lying in the gutter. Slinking about among the houses of the poor, if they see a door unlatched or a window left open, they creep inside and steal the only copper kettle, or a last set of patched robes.

'Is it not reasonable to assume that such a man when passing through Half Moon Street happened to discover Wang's secret visits to Pure Jade? Such a ruffian would immediately see the chance of having a woman who could not protest against his usurping her secret lover's place. However, Pure Jade defended herself. Probably she tried to shout or to reach the door in order to rouse her parents. Then he strangled her. Having committed this foul deed he calmly ransacked his victim's room for valuables, and made off with the only trinket she had.'

Judge Dee paused and drank another cup of tea.

Sergeant Hoong slowly nodded his head. Then he said:

'Your Honour has made it clear indeed that Candidate Wang did not commit this double crime. Yet I cannot see any definite evidence we could use in court.'

'If you want tangible proof,' Judge Dee answered, 'you shall have it! In the first place, you have heard the coroner's evidence. If Candidate Wang had strangled Pure Jade, his long fingernails would have left deep gashes in the girl's throat; the coroner only found shallow nailmarks, although the skin was broken here and there. This points to the short, uneven nails of a vagrant ruffian.