Mr. Sheldon the dentist sat up till the small hours that night, as he had done for many nights lately. He finished his work in the torture-chamber, and went up to the common sitting-room, or drawing-room as it was called by courtesy, a little before midnight. The servants had gone to bed, for there was no regular nightly watch in the apartment of the invalid. Mrs. Halliday lay on a sofa in her husband's room, and Nancy Woolper slept in an adjoining apartment, always wakeful and ready if help of any kind should be wanted.

The house was very quiet just now. Philip Sheldon walked up and down the room, thinking; and the creaking of his boots sounded unpleasantly loud to his ears. He stopped before the fireplace, after having walked to and fro some time, and began to examine some letters that lay upon the mantelpiece. They were addressed to Mr. Halliday, and had been forwarded from Yorkshire. The dentist took them up, one by one, and deliberately examined them. They were all business letters, and most of them bore country post-marks. But there was one which had been, in the first instance, posted from London and this letter Mr. Sheldon examined with especial attention.

It was a big, official-looking document, and embossed upon the adhesive envelope appeared the crest and motto of the Alliance Insurance Office.

"I wonder whether that's all square," thought Mr. Sheldon, as he turned the envelope about in his hands, staring at it absently. "I ought to make sure of that. The London postmark is nearly three weeks old." He pondered for some moments, and then went to the cupboard in which he kept the materials wherewith to replenish or to make a fire. Here he found a little tin tea-kettle, in which he was in the habit of boiling water for occasional friendly glasses of grog. He poured some water from a bottle on the sideboard into this kettle, set fire to a bundle of wood, and put the kettle on the blazing sticks. After having done this he searched for a tea-cup, succeeded in finding one, and then stood watching for the boiling of the water. He had not long to wait; the water boiled furiously before the wood was burned out, and Mr. Sheldon filled the tea-cup standing on the table. Then he put the insurance-letter over the cup, with the seal downwards, and left it so while he resumed his walk. After walking up and down for about ten minutes he went back to the table and took up the letter. The adhesive envelope opened easily, and Mr. Sheldon, by this ingenious stratagem, made himself master of his friend's business.

The "Alliance" letter was nothing more than a notice to the effect that the half-yearly premium for insuring the sum of three thousand pounds on the life of Thomas Halliday would be due on such a day, after which there would be twenty-one days' grace, at the end of which time the policy would become void, unless the premium had been duly paid.

Mr. Halliday's letters had been suffered to accumulate during the last fortnight. The letters forwarded from Yorkshire had been detained some time, as they had been sent first to Hyley Farm, now in the possession of the new owner, and then to Barlingford, to the house of Georgy's mother, who had kept them upwards of a week, in daily expectation of her son-in-law's return. It was only on the receipt of a letter from Georgy, containing the tidings of her husband's illness, that Mr. Halliday's letters had been sent to London. Thus it came about that the twenty-one days of grace were within four-and-twenty hours of expiring when Philip Sheldon opened his friend's letter.

"This is serious," muttered the dentist, as he stood deliberating with the open letter in his hand; "there are three thousand pounds depending on that man's power to write a check!"

After a few minutes' reflection, he folded the letter and resealed it very carefully.

"It wouldn't do to press the matter upon him to-night," he thought; "I must wait till to-morrow morning, come what may."

CHAPTER VI.