Author's Note: I have done research into septic infection, the degrees of danger that it can cause, and the progress of antibiotic medicine throughout history.

A man in Germany was going about discovering antibacterials in the late 1880's.

So, for the sake of this story, Watson has managed to get hold of this information and import the new medicine through Holmes, who (obviously) has a lot of contacts in different countries, that come under the categories of "Clever Men" and "Men Who Fit Into The Plot Of This Narrative".

Otherwise there is no cure for Sepsis in the 1800s, Holmes will die, and I shall have no story!

4
Too fragile, this place, and I'm holding my breath
This is my head, stuck in the sun
This is the cold that resides in my hand
And we have learned all there is about silence.

The bell was ringing as though a maddened devil was hanging off it outside.
"Josephine!" John shouted down the stairs, "Would you hurry up and answer that? It sounds urgent!"

That girl really did take her time.
John was becoming impatient with her. She wasn't at all like Mrs. Hudson - and of course, she wouldn't be. She was a maid. And they could barely afford to keep her as it was.

"Josephine!" he fairly yelled again, and eventually footsteps came running, and the frantic doorbell was replaced by slightly calmer voices.
Only slightly.

From what he could deduce, their visitor was a female, and a distraught one at that.
Mary entered the study and stood staring at him, in a kind of mild bewildered concern.

"It's a woman. A frightened woman." she remarked softly.
"Yes, Mary. She does sound rather distressed, doesn't she."
"Do you know who it is?"
"I don't recognise the voice one jot."

Apparently Josephine didn't recognise her face, either, because she called up the stairs, "A stranger to see you, Sir! Apparently on urgent business!"

"Perhaps it's a patient in immediate danger."
"Yes, darling." he threw back at his wife obligingly, as he limped out of the room and descended to the front door without haste.

He wasn't in the mood for urgent business.
He hadn't heard words like urgent business tossed around in such a way since... well, since that time.

He didn't even dare to think of a name, but his heart felt skewered upon an invisible knife regardless.
The months that had passed since his swift and grey-coloured return to England had not healed him in the slightest.

Every day, in his mind, he still stood leaning over that solid balcony, looking down into an impenetrable barrier of mist and water. The gulf of hell - his own, personal hell.
The bottomless pit that had swallowed his truest friend and companion, mercilessly, without a hint of remorse.

What was that phrase of Nietzsche's? - If you gaze long enough into the abyss, the abyss will also gaze into you.

He had gazed into those endless, dizzy depths, and they had looked back up at him. Looked long and hard, with a cold, unrepenting, all-seeing stare. It had imprinted something upon his soul that was black, and poisonous, and relentless.

It had jeered at him, because it had taken the one thing he could not now live without.

He suddenly realised that he had been staring straight at his visitor without greeting her for quite some time.
Rather, staring straight through her.
She looked uncomfortable under his otherworldly gaze.

"John Watson?" she enquired politely, though firmly. She was obviously on very urgent business.
"That would be me."
"I need you to come with me, without delay. There is a man in my house dying of sepsis, and he has specifically required that you see him. He is barely sane."

John's stomach turned over.

"Did he say what his name was?"
"Not at all. He scarcely knows himself. He is unconscious for most of the time. He desperately needs your aid - please, come with me quickly."

He had no idea who this strange demanding man could be, but now that Death was looming over the situation, he lost no time. He was not the man to remain cool and self-absorbed when somebody's life hung in the balance.

Running back up to his study, he gathered his emergency medical kit together, taking care to include the wedding gift Holmes had once given him, and the newfangled antibacterial concoctions that were apparently an effective cure for a vast scope of infections and illnesses.

He hadn't tried them out yet, but this was as good a time as any.

The sudden rush of adrenaline, the notion that he was needed, dampened the sense of hollow agony that he had felt so acutely only moments ago.

Flying back down the steps, throwing on his frock coat and donning a hat, he called out to Mary that he must run off, and that it was indeed an endangered patient.
He swiftly followed the still-nameless woman out onto the street, slamming the door behind him.

His steps were brisk, without a hint of a limp.
He was attending urgent business once again.