ON his arrival in London, Mountjoy went to the Nurses’ Institute to inquire for Mrs. Vimpany.

She was again absent, in attendance on another patient. The address of the house (known only to the matron) was, on this occasion, not to be communicated to any friend who might make inquiries. A bad case of scarlet fever had been placed under the nurse’s care, and the danger of contagion was too serious to be trifled with.

The events which had led to Mrs. Vimpany’s present employment had not occurred in the customary course.

A nurse who had recently joined the Institute had been first engaged to undertake the case, at the express request of the suffering person — who was said to be distantly related to the young woman. On the morning when she was about to proceed to the scene of her labours, news had reached her of the dangerous illness of her mother. Mrs. Vimpany, who was free at the time, and who felt a friendly interest in her young colleague, volunteered to take her place. Upon this, a strange request had been addressed to the matron, on behalf of the sick man. He desired to be “informed of it, if the new nurse was an Irishwoman.” Hearing that she was an Englishwoman, he at once accepted her services, being himself (as an additional element of mystery in the matter) an Irishman!

The matron’s English prejudices at once assumed that there had been some discreditable event in the man’s life, which might be made a subject of scandalous exposure if he was attended by one of his own countrypeople. She advised Mrs. Vimpany to have nothing to do with the afflicted stranger. The nurse answered that she had promised to attend on him — and she kept her promise.

Mountjoy left the Institute, after vainly attempting to obtain Mrs. Vimpany’s address. The one concession which the matron offered to make was to direct his letter, and send it to the post, if he would be content with that form of communication.

On reflection, he decided to write the letter.

Prompt employment of time might be of importance, if it was possible to prevent any further communication with Lord Larry on the part of his Irish correspondent. Using the name with which Iris had provided him, Hugh wrote to inquire if it was familiar to Mrs. Vimpany, as the name of a person with whom she had been, at any time, acquainted. In this event, he assured her that an immediate consultation between them was absolutely necessary in the interests of Iris. He added, in a postscript, that he was in perfect health, and that he had no fear of infection — and sent his letter to the matron to be forwarded.

The reply reached him late in the evening. It was in the handwriting of a stranger, and was to this effect:

“Dear Mr. Mountjoy,— It is impossible that I can allow you to run the risk of seeing me while I am in my present situation. So serious is the danger of contagion in scarlet fever, that I dare not even write to you with my own hand on note-paper which has been used in the sick room. This is no mere fancy of mine; the doctor in attendance here knows of a case in which a small piece of infected flannel communicated the disease after an interval of no less than a year. I must trust to your own good sense to see the necessity of waiting, until I can receive you without any fear of consequences to yourself. In the meantime, I may answer your inquiry relating to the name communicated in your letter. I first knew the gentleman you mention some years since; we were introduced to each other by Lord Harry; and I saw him afterwards on more than one occasion.”

Mountjoy read this wise and considerate reply to his letter with indignation.

Here was the good fortune for which he had not dared to hope, declaring itself in favour of Iris. Here (if Mrs. Vimpany could be persuaded to write to her friend) was the opportunity offered of keeping the hot-tempered Irish husband passive and harmless, by keeping him without further news of the assassin of Arthur Mountjoy. Under these encouraging circumstances the proposed consultation which might have produced such excellent results had been rejected; thanks to a contemptible fear of infection, excited by a story of a trumpery piece of flannel!

Hugh snatched up the unfortunate letter (cast away on the floor) to tear it in pieces and throw it into the waste-paper basket — and checked himself. His angry hand had seized on it with the blank leaf of the note-paper uppermost.

On that leaf he discovered two little lines of print, presenting, in the customary form, the address of the house at which the letter had been written! The writer, in taking the sheet of paper from the case, must have accidentally turned it wrong side uppermost on the desk, and had not cared to re-copy the letter, or had not discovered the mistake. Restored to his best good-humour, Hugh resolved to surprise Mrs. Vimpany by a visit, on the next day, which would set the theory of contagion at defiance, and render valuable service to Iris at a crisis in her life.

Having time before him for reflection, in the course of the evening, he was at no loss to discover a formidable obstacle in the way of his design.

Whether he gave his name or concealed his name, when he asked for Mrs. Vimpany at the house-door, she would in either case refuse to see him. The one accessible person whom he could consult in this difficulty was his faithful old servant.

That experienced man — formerly employed, at various times, in the army, in the police, and in service at a public school — obtained leave to make some preliminary investigations on the next morning.

He achieved two important discoveries. In the first place, Mrs. Vimpany was living in the house in which the let............