These reflections passed swiftly through his mind in the intervals of a very desultory conversation. As he reached his conclusion, he once more looked up at Varney. And then he received something like a shock. At the moment no one was speaking, and Varney was sitting with his eyes somewhat furtively fixed on Margaret’s downcast face. Now, to an experienced observer, there is something perfectly unmistakable in the expression with which a man looks at a woman with whom he is deeply in love. And such was the expression that Thorndyke surprised on Varney’s face. It was one of concentrated passion, of adoration.
Thorndyke was completely taken aback. This was an entirely new situation, calling for a considerable revision of his conclusions and also of his sympathies. An eliminated blackmailer is one thing; Uriah’s wife is another and a very different one. Thorndyke was rather puzzled, for though the previous hypothesis hung fairly together, it was now weakened by the possibility that the murder had been committed merely to remove a superfluous husband. Not that it made any practical difference. He was concerned with the fact of Purcell’s murder. The motives were no affair of his.
His reflections were interrupted by a question from Margaret.
“You haven’t been down to Cornwall, I suppose, since you came to see us at Sennen in the summer?”
“No; I have not, but Professor D’Arcy has; and he is starting for another trip at the end of next month.”
“Is he still in search of worms? It was worms that you were going to look for, wasn’t it?”
“Yes, marine worms. But he is not fanatical on the subject. All marine animals are fish that come to his net.”
“You are using the word net in a metaphorical sense, I presume,” said Varney. “Or does he actually use a net?”
“Sometimes,” replied Thorndyke. “A good many specimens can be picked up by searching the shore at low tide, but the most productive work is done with the dredge. Many species are found only below low-water mark.”
“Is there anything particularly interesting about marine worms?” Margaret asked. “There always seems something rather disgusting about a worm, but I suppose that is only vulgar prejudice.”