Their maid was out at the fête, Mrs. Merrowdene explained, when they arrived at the charming old-world cottage. She went into her room to remove her hat, returning to set out tea and boil the kettle on a little silver lamp. From a shelf near the fireplace she took three small bowls and saucers.

“We have some very special Chinese tea,” she explained. “And we always drink it in the Chinese manner—out of bowls, not cups.”

She broke off, peered into a bowl and exchanged it for another with an exclamation of annoyance.

“George—it’s too bad of you. You’ve been taking these bowls again.”

“I’m sorry, dear,” said the professor apologetically. “They’re such a convenient size. The ones I ordered haven’t come.”

“One of these days you’ll poison us all,” said his wife with a half laugh. “Mary finds them in the laboratory and brings them back here, and never troubles to wash them out unless they’ve anything very noticeable in them. Why, you were using one of them for potassium cyanide the other day. Really, George, it’s frightfully dangerous.”

Merrowdene looked a little irritated.

“Mary’s no business to remove things from the laboratory. She’s not to touch anything there.”

“But we often leave our teacups there after tea. How is she to know? Be reasonable, dear.”

The professor went into his laboratory, murmuring to himself, and with a smile Mrs. Merrowdene poured boiling water on the tea and blew out the flame of the little silver lamp.

Evans was puzzled. Yet a glimmering of light penetrated to him. For some reason or other, Mrs. Merrowdene was showing her hand. Was this to be the “accident?” Was she speaking of all this so as deliberately to prepare her alibi beforehand? So that when, one day, the “accident” happened, he would be forced to give evidence in her favour. Stupid of her, if so, because before that—

Suddenly he drew in his breath. She had poured the tea into the three bowls. One she set before him, one before herself, the other she placed on a little table by the fire near the chair her husband usually sat in, and it was as she placed this last one on the table that a little strange smile curved round her lips. It was the smile that did it.

He knew!

A remarkable woman—a dangerous woman. No waiting—no preparation. This afternoon—this very afternoon—with him here as witness. The boldness of it took his breath away.

It was clever—it was damnably clever. He would be able to prove nothing. She counted on his not suspecting—simply because it was “so soon.” A woman of lightning rapidity of thought and action.

He drew a deep breath and leaned forward.

“Mrs. Merrowdene, I’m a man of queer whims. Will you be very kind and indulge me in one of them?”

She looked inquiring but unsuspicious.