As the boy disappeared on a fake errand, Long Sin, with the real note hurried down-town, smiling wickedly.

“They have discovered the fever, Master,” he reported in the den.

Wu was beside himself with rage.  Before he could speak, however, Long Sin spread out Godowski’s message.  “But I have this,” he added.

It took merely a glance to suggest to Wu a new plan of action.  He rose and moved quickly into the back room.  “Come,” he ordered Weepy Mary.  “You must dress up as a nurse—­immediately.”

Quickly she donned one of the numerous disguises while Wu planned his campaign.

“Here,” he directed when she was ready, handing her a little vial.  “You must infect every instrument the doctor uses on Kennedy and Jameson,—­see?”

She nodded and a moment later was on her way uptown.

. . . . . . .

Meanwhile Godowski himself had arrived at our apartment, much to the relief of our friend Johnson, and was unpacking his instruments.

Quickly he improvised two operating tables, and placed one of us on each.  Then, with his assistant, he put on his white robes, mask, gloves and other precautions for asepsis, setting out the apparatus for the intravenous administration of the drug that would kill the spirillum.  Godowski was busy with the atoxyl, mixing it in a normal salt solution.  He would drop in a few drops of an acid, then a few drops of an alkaline solution, so as to keep the mixture neutral.  Finally, he poured the solution into a container, to the bottom of which was attached a long tube.  This container he raised high over our heads, clamping the tube.

Then he fastened a tiny needle to the end of the tube, so that it could be inserted in our arms, catching skillfully a vein—­a very difficult piece of work in which he excelled.  The liquid would then flow by the force of gravity from the container down through the tube, through the hollow needle and into the vein where it would act on the germs of the fever.

They had finished their preparations and were waiting for Miss Septix.  “She ought to be here, now,” muttered Godowski impatiently, looking at his watch.

Just then a cab drove up outside.

“Perhaps that is she,” he exclaimed.  “It must be.”

A few moments later the door of the apartment opened.  His face showed his disappointment.  It was a stranger.

“Miss Septix is ill,” she introduced, “and sent me to take her place.”

The doctor looked about.  “Very well, then,” he said briskly, seeing his preparations.  “Are you ready to go ahead?”

She nodded and threw off her coat that covered her immaculate white uniform.

The specialist plunged whole-heartedly into his work of saving us now.  “Hand me that needle, please,” he directed the false nurse.

She moved over to the table near-by and took it up, pausing only long enough to dip it secretly into a vial she carried with her.