'Whatever it is, it is our business to prevent his doing it.'

'And where do you think they have been taken?'

'That it will be our immediate business to endeavour to discover,--and here, at any rate, we are at Waterloo.'

CHAPTER XLII

THE QUARRY D0UBLES

I turned towards the booking-office on the main departureplatform. As I went, the chief platform inspector, PembertonBellingham, with whom I had some acquaintance, came out of hisoffice. I stopped him.

'Mr Bellingham, will you be so good as to step with me to thebooking-office, and instruct the clerk in charge to answer one ortwo questions which I wish to put to him. I will explain to youafterwards what is their exact import, but you know mesufficiently to be able to believe me when I say that they referto a matter in which every moment is of the first importance.'

He turned and accompanied us into the interior of the booking-case.

'To which of the clerks, Mr Champnell, do you wish to put yourquestions?'

'To the one whom issues third-class tickets to Southampton.'

Bellingham beckoned to a man who was counting a heap of money, andapparently seeking to make it tally with the entries in a hugeledger which lay open before him,--he was a short, slightly-builtyoung fellow, with a pleasant face and smiling eyes.

'Mr Stone, this gentleman wishes to ask you one or two questions.'

'I am at his service.'

I put my questions.

'I want to know, Mr Stone, if, in the course of the day, you haveissued any tickets to a person dressed in Arab costume?'