"That's the formula for the ink!" he said. "Now we've got the big thing we wanted! And Mr. Culthwaite will tell you how he got it."
Culthwaite, after allowing Hetherwick to look at the paper, carefully replaced it in his pocket-book. There was an air of anxiety about him and about his partner concerning which Hetherwick began to make guesses—they looked as if they were uncertain and uneasy. But Culthwaite was ready enough to tell his story.
"We got it in this way," he said. "And I may as well say, as I've already said to you, Mr. Matherfield, that I don't think we should have got it at all if you police people hadn't been so reticent on that one particular point—if you'd noised it abroad about Hannaford's secret we might have been forewarned. However, some little time ago, a man whom we knew as Basing, and whom I firmly believe to be the Baseverie that we've read about in the papers this morning—a man, mind you, that we'd done business with now and then during the last year or so—came to us and offered us the formula for a new black ink which he asserted would drive every known ink off the market, all over the world! He made extravagant claims for it; he swore it was the first absolutely perfect writing fluid ever invented. He brought a sample of it which he'd made up himself—he put it to various tests. But he did more—he offered us the use of the secret formula so that we ourselves could make and test it before deciding whether we'd fall in with his suggestion, which was that we should offer him a lump cash sum for the formula. Well, we did make the ink, from the formula, and we did test it, and there is no doubt about it—it is all, and perhaps more, that Basing, or Baseverie claimed for its excellence. I needn't go into the drawbacks attaching to most well-known inks—this has none of them. And when Basing came back to us, a few days ago, we decided to buy the formula from him. We agreed upon a cash price, and day before yesterday we paid the amount over—at our office in East Ham."
"Yes?" said Hetherwick quietly. "And—what was the price agreed upon?"
The two partners exchanged a glance; it seemed to Rhona, who was watching them intently, that they looked more uneasy than before. But Culthwaite replied with promptitude.
"Ten thousand pounds!"
"How did you pay him?" asked Hetherwick. "In cash?"
"No—by open cheque, at his own request. That, of course, was as good as cash. But," continued Culthwaite, "as soon as we read the newspapers this morning, we—that is, I, for I read the whole thing on my way to business—went at once to our bank to see if the cheque had been cashed. It had—an hour or two after we'd handed it to Basing. He'd taken the amount in Bank of England notes."
Hetherwick looked at Matherfield.
"Of course," he remarked, as if he were asking a question, "that formula belongs to Miss Hannaford? Baseverie had no right to sell it—he stole it?"