‘No more kailyard talk for me,’ he thought, with satisfaction.

The head of the detective department arrived in no long time.  He was in evening dress.  Merton rose and bowed.

‘What’s your story, sir?’ the chief asked; ’it has brought me from a dinner party at my own house.’

‘I deeply regret it,’ said Merton, ’though, for my purpose, it is the merest providence.’

‘What do you mean, sir?’

‘Your subordinate has doubtless told you all that I told him?’

The chief nodded.

‘Do you—­I mean as an official—­believe me?’

‘I would be glad of proof of your personal identity.’

’That is easily given.  You may know Mr. Lumley, the Professor of Toxicology in the University here?’

‘I have met him often on matters of our business.’

’He is an old college friend of mine, and can remove any doubts you may entertain.  His wife is a tall woman luckily,’ added Merton to himself, much to the chief’s bewilderment.

‘Mr. Lumley’s word would quite satisfy me,’ said the chief.

‘Very well, pray lend me your attention.  This affair—­’

‘The body snatching at Kirkburn?’ asked the chief.

‘Exactly,’ said Merton.  ’This affair is very well organised.  Your house is probably being observed.  Now what I propose is this.  I can go nowhere dressed as I am.  You will, if you please, first send a constable, in uniform, to your house with orders to wait till you return.  Next, I shall dress, by your permission, in any spare uniform you may have here and in that costume I shall leave this office and accompany you to your house in a closed cab.  You will enter it, bring out a hat and cloak, come into the cab, and I shall put them on, leaving my policeman’s helmet in the cab, which will wait.  Then, minutes later, the constable will come out, take the cab, and drive to any police office you please.  Once within your house, I shall exchange my uniform for any old evening suit you may be able to lend me, and, when your guests have departed, you and I will drive together to Professor Lumley’s, where he will identify me.  After that, my course is perfectly clear, and I need give you no further trouble.’

‘It is too complicated, sir,’ said the chief, smiling.  ’I don’t know your name?’

‘Merton,’ said our hero, ‘and yours?’

’Macnab.  I can lend you a plain suit of morning clothes from here, and we don’t want the stratagem of the constable.  You don’t even need the extra trouble of putting on evening dress in my house.’

‘How very fortunate,’ said Merton, and in a quarter of an hour he was attired as a simple citizen, and was driving to the house of Mr. Macnab.  Here he was merely introduced to the guests—­it was a men’s party—­as a gentleman from England on business.  The guests had too much tact to tarry long, and by eleven o’clock the chief and Merton were ringing at the door bell of Professor Lumley.  The servant knew both of them, and ushered them into the professor’s study.  He was reading examination papers.  Mrs. Lumley had not returned from a party.  Lumley greeted Merton warmly.