The million pound banknote

'They went to the Continent, by what route I cannot say. They said they would be back in a month.'

'A month! Oh, this is awful! If you can't give me some sort of idea of how to get word to them, it's of the greatest importance that I at least see some member of the family immediately. There's been an immense mistake made. Once they know that they'll be back before night. Will you tell them I've been here, and that I will keep coming till it's all made right, and they needn't be afraid?'

'They said you would be here in an hour to make inquiries, but I must tell you it's all right, they'll be here on time and expect you.'

So I had to give it up and go away. What a riddle it all was! I was like to lose my mind. They would be here 'on time'. What could that mean? Oh, the letter would explain, maybe. I had forgotten the letter; I got it out and read it. This is what it said:
You are an intelligent and honest man, as one may see by your face. We conceive you to be poor and a stranger. Enclosed you will find a sum of money. It is lent to you for thirty days, without interest. Report to this house at the end of that time. I have a bet on you. If I win it you shall have any situation that is in my gift - any, that is, that you shall be able to prove yourself familiar with and competent to fill.'

Vocabulary:

The Continent: How Britons often refer to mainland Europe
Get word to: Contact; give a message
Immense: Very big
Riddle: A question which is also a puzzle
Lose one's mind: Go mad
Conceive: Get the idea
Interest: Extra money you pay for money you have borrowed
Situation: Here it means 'job'