The following story is with thanks to my friend and Beta's "mad sister" (the friend's description, not mine), who gave me the prompt: [Spoiler (click to open)] "death by soap". It certainly had me thinking...
I entered our sitting room to find Sherlock Holmes already there. He was curled up in his armchair with a blanket about his shoulders as he stared sightlessly into our unlit hearth.
"Holmes?" I approached him slowly, expecting to find a discarded needle close by.
I received no reaction from my friend, but I did see him give a shiver.
I hastily lit a fire in the hearth before turning my attention to my companion. He was indeed shivering violently, but a sheen of sweat at his brow was visible in the firelight. I touched his forehead to find that it was burning hot.
He hissed and gave a start. "Your hands are freezing!" he gasped at me.
"Holmes!" I gave a sigh of relief and crouched before him. "How are you feeling?"
He groaned and waved a dismissive hand.
"No, talk to me. It is obvious that you are unwell; tell me what is wrong."
He groaned again and clutched at his abdomen. "I believe I have eaten something that I should not have done."
"Are you nauseous?"
He moaned. "Yes... I feel ill. Terribly so!"
"If it is indeed something that you have had to eat, it is best to allow you to rid yourself of it," I informed him apologetically. "But I can at least cool you."
"You do not want to stay with me," he whispered.
I took his hand in mine firmly. "I am a doctor Holmes. I have seen worse, I assure you."
His lips quirked in a small, fleeting smile. "Thank you."
The day was far from pleasant. Holmes could barely swallow the water that I plied him with by the time mid morning came and he soon became weak from vomiting. I did my utmost to comfort him, but there was little that I could do.
When evening arrived, my companion seemed to be on the road to recovery. I encouraged him to have a few bites of some dry toast and to drink some more water.
My companion was much like his usual self the following morning. He chaffed at my directives to continue to eat plain foods and to drink only water, but heeded my advice when I reminded him that his digestion had been terribly upset.
It was at lunch time that I saw signs of relapse. My friend was suddenly dreadfully pale, even by his standards, and trembling.
"Holmes? Are you all right?"
He waved my concern aside and staggered into the bathroom. The vomiting began again.
"I obviously should not have tried to eat," my companion mumbled as I made him comfortable upon our sofa.
"If that were the case, you would have been sick during the night," I replied as I cooled his brow. I could not understand it, but I said nothing. I did not wish to alarm my ill friend.
"What is wrong with me?" his eyes widened and he stared at me in sudden horror. "Leave me!"
I reached for the bucket that I had ensured was close at hand. Holmes does not like to be seen vomiting and so I believed that he was about to be sick again.
He shook his head weakly. "If I do not have food poisoning you might contract this hateful illness from me."
I set aside the bucket and took his hand in mine. "I shan't abandon you."
I again received a wan, fleeting smile.
So this continued as the days went by. My companion would begin to recover, only to suddenly relapse with little or no warning. I found myself at my wits' end. Nothing that I attempted seemed to work and poor Holmes was growing weaker and his symptoms more severe.
I did not fall ill, though watching my friend suffer so upset me terribly. I knew not what to do.
"Read to me?" Holmes requested one evening, as I attempted to make him comfortable. "I need a distraction."
I looked at our many books. "What should I read?"
"Anything. I care not."
I patted his hand and went to our bookcase. As I tried to decide on reading material my gaze fell upon one of my friend's books.
"Holmes... Could you have been poisoned?"
"How?" he asked tiredly. "The poisoner would have had to somehow keep administering the poison to me."
How indeed. I had taken away his tobacco when he had first become unwell and he was barely eating. How indeed could a poison have been administered to him but not to me?
I returned to his side. "We shall use your methods Holmes. What have you done each time that you have relapsed?"
He groaned. "I do not know!"
I took his hand in mine and squeezed it sympathetically. He was too ill and weak to be able to think.
"When you begin to recover, I want you to remain here on this sofa. You are not to do anything that you have not been doing while you were unwell."
"For how long?"
"I am not sure. We shall call this an experiment. If you do not relapse again, then it will be a strong indication that you have somehow been poisoning yourself."
Holmes closed his eyes and nodded.
"How are you feeling?"
He moaned. "Horrible. I should like to bathe or otherwise attend to my toilet; I am terribly sticky."
I had not become ill and we had both bathed on the same evening. It could not have been our bath salts. Indeed, it could not have been anything from our bathroom, for all of our toiletries are shared.
"I am hot."
I nodded and gently cooled my companion's brow. "You shall be all right Holmes," I promised. "If you have ceased to feel cold, your fever has peaked; you should begin to improve soon."
I was right. Within an hour the fever started to diminish and the vomiting gradually cease.
"I should like to wash myself and change my clothes," my friend reminded me. "Would you please allow me to do so?"
I shook my head. "I want you to remain here."
Holmes continued to drink only water, which I ordered our housekeeper to boil first to ensure that there were no impurities in it (as is my habit when I attend to the ill), and eat only dry toast that night and the following day. He did not again relapse.
"It would seem that we have two possibilities Watson," he remarked. "Either the illness has finally run its course or you are correct and I have somehow been poisoned. Repeatedly."
I knew that the thought of his unwittingly poisoning himself disturbed him greatly, for it was the same with me. Holmes is terribly cautious and so the poisoner would have had to have been clever indeed.
"It is not my tobacco; you have not permitted me to smoke it. Might I have some now?"
I agreed and presented him with his clay pipe and enough tobacco for one smoke.
"I am to be rationed Doctor?" he enquired of me with a smirk.
"You have been terribly ill old fellow," I reminded him, "and it may not be due to poison. I hardly want to cause you to relapse again."
Holmes' condition continued to improve but he also continued to complain that he was sticky and wished to attend his toilet. I eventually agreed to run him a bath as I knew that to be safe.
My friend exited our bathroom wrapped snugly in towels and took to his chair beside the fireplace, having both bathed and brushed his teeth. He announced that he felt much improved.
"I am glad," I told him with a smile.
He returned my smile fleetingly and then rubbed at his forehead. "How could I be poisoned in my own house?"
"Have you received any gifts lately?"
He shook his head. "Indeed not. You know that I am extraordinarily careful in regard to gifts in any case."
He was indeed right and I said as much. "Then what do you have that was new when you first became unwell?"
He closed his eyes and permitted his head to sink forward until his chin rested upon his chest. He remained thus for several minutes.
I allowed myself to doze. I had not slept properly since the onset of my companion's illness and I was somewhat diminished as a result.
"Soap!" my friend announced suddenly, causing me to give a start.
"What?" I asked as I attempted to wake up.
"I have a fresh bar of soap, which was new when I became unwell," he frowned and snorted dismissively. "But that cannot be it," he grumbled, impatiently drumming his fingers upon the arm of his chair. "I have used the same shop for years."
"Is it the only thing that you can think of?" I asked of him.
He nodded.
"Then should I try it on myself and see what happens?" It is, after all, precisely what he would do.
His eyes widened in alarm. "No!" he calmed himself hastily as if his outburst had not occurred. "No my dear fellow. It would be quite inconclusive, for you have scarcely left my side since the onset of my illness; if you were to become unwell it could easily be due to contagion. No, I shall have to try something else."
I watched Holmes prepare his chemistry set for an experiment. He then stood and retrieved the questionable bar of soap from his bedroom.
As time wore on, I started to doubt that my companion's illness could have been caused by the soap, for every test proved negative. Holmes started to pore over his book on poisons and requested that I speak not a word.
Eventually, my friend tossed aside his book with frustration. "It will not do Watson. If there is indeed a poison within the soap's make-up, it is untraceable. Even to me."
He instructed me to buy another bar, giving the name of his preferred brand and advising me of where it should be purchased from.
Holmes took the new bar of soap from me and I watched as he first took a sample from that and then yet another sample from the first bar.
I did not mean to fall asleep, but I was suddenly jerked into wakefulness by a "Ha ha!" from my companion.
"This is indeed the means by which I was poisoned!" Holmes cried with excitement as he gestured to the soap. "I know not what the substance is, but there is an extra ingredient in the bar that I have been using. Hum! Very clever."
"Thank God!" I remarked emphatically. "I am only glad that you are all right and that we know what was wrong Holmes."
He agreed quietly. Then he very carefully destroyed the bar of soap that had made such an impact upon his health.