Holmes slept steadily, barely stirring, for a further four hours. Whenever his eyelids flickered or his breathing seemed to hitch in his chest as he frowned, Irene would gently stroke his hair until his face smoothed and he relaxed again.
Watson had quietly removed the violin from unresisting fingers, carefully replacing it in its case, then drawn the blanket up over Holmes to his chest before retreating to his chair once more. He flicked idly through the morning paper; he quietly read out a few items of interest to Irene much as he usually did with Holmes without really thinking about it. Irene listened politely, smiling gently at Watson's inclusion of her in what was obviously a morning ritual normally shared with Holmes.
Mrs Hudson came to fetch the coffee tray and was torn between giving Irene a disapproving glare and expressing approval of Holmes' somnolent state; she settled instead for a tight-lipped nod before departing. Irene smirked to herself as Watson went through his morning correspondence, seemingly oblivious to the interplay between the two women.
Watson, for his part, was completely aware of the unvoiced exchange between the two women and concealed his own amusement rather better than Irene; if she had been playing closer attention she might have caught the slight twinkle in his blue eyes. Certainly he was more aware than she was when Holmes' breathing shifted pattern towards that of waking. He rose to his feet and excused himself to call down to Mrs Hudson for tea and a bite of lunch.
"Somewhat early for lunch I would have thought?" remarked Irene. "It's barely past noon, after all."
"Rather late for breakfast however, and Holmes needs to eat," replied Watson, making his way over to the settee and kneeling down beside them. "How are you feeling, Holmes old boy?"
Irene glanced down in surprise as Holmes shifted slightly. "Well spotted, Watson. How long were you aware I was awake?" he said quietly, eyes still closed.
"You still haven't got the hang of maintaining a sleeping breath pattern," replied Watson with a smile as Holmes opened his eyes and glanced over at him. Holmes smiled ruefully.
"Only a doctor – and a particularly observant one at that – would know however," he remarked. Watson inclined his head in acknowledgement of the compliment.
"After so long around you, Holmes, something was bound to rub off on me," he replied. He patted Homes' arm. "Come on, up with you now; I dare say a good cup of tea and something to eat is just what you could do with right now."
Holmes sat up with some assistance from Irene and ran his hands slowly over his face. "I feel like I've been dead to the world for days," he remarked quietly.
"Well, in a way you have," replied Watson as he struggled up to his feet then reached for the newspaper. He opened it to the advert then handed it to Holmes, who rose to his feet and slowly strode towards the window as he studied it carefully. He sat down upon the windowsill then twisted around sideways to draw his feet up onto the sill as he leaned back against the window frame. Flipping the newspaper over to the front page he began to go through it in his usual idiosyncratic manner, pulling out certain pages and tossing them over onto his desk for later study before pulling out his pipe from his pocket, filling and lighting it then puffing steadily upon it as he turned his attention to the rest of the paper.
Watson opened the door as Mrs Hudson came up the stairs; he held it open for her as she entered bearing a tray.
"I see you must be feeling better, Mr Holmes; you're back to poisoning the air already. Have you not had enough of the London smog already in your lungs but that you must pollute them further?" she sniffed disdainfully as she set the tray down then moved to the windows, throwing open the long drapes and lifting the sash windows. Holmes scooted to one side as she reached for the window he sat in and flapped the newspaper at her.
"Away with you, Nanny; can't you see I'm busy, woman?"
"Away with you yourself!" she retorted, shooing him away from the window with her apron.
"The woman's a menace; Watson, we are positively besieged by the female of the species – this simply will not do," Holmes muttered as he strode rapidly out of her way as she returned to the doorway. She glanced back over her shoulder at him, then winked conspiratorially at Watson as he passed a cup of tea to Holmes, who stood by the fire with his back to them both.
"You're obviously feeling better, Sherlock," remarked Irene as she reached for the teapot and poured herself a cup of tea. He glared at her over the rim of his own teacup as he threw the remains of the newspaper down into the coal scuttle.
Suddenly he went still, staring into space for a few minutes. "But of course," he said softly. "How couldI have missed it? I am a damned fool..." Setting down his teacup he snatched up one of the silver teaspoons and leapt over the settee, bounding across the room to the table where his chemicals and apparatus were spread out. Sitting himself down he set the teaspoon over a piece of paper and took up a small file. He began to rasp off a small pile of grey powder findings which he then carefully tipped into a test tube.
Irene rose from her seat; she and Watson exchanged glances then silently ghosted closer to Holmes as he hunched over the table, long slender fingers seeking out then selecting a glass bottle of acid. Gently he siphoned up a small amount with a pipette then he added it to the silver powder. Sealing his thumb over the end, he swirled the liquid swiftly, and a reddish-brown gas began to form.
"There, see; do you see it, Watson? Do you see it?" He turned to Watson, his eyes bright with triumph. "What does that remind you of?"
"The smog the night we almost caught the Cessarine Majeste!" exclaimed Watson.
"Yes indeed!" replied Holmes. "And if I am not mistaken..." He removed his thumb from the end of the tube and a queer, unpleasantly sourish smell wafted out into the room. Irene reeled back, putting her handkerchief over her nose.
"What is that stench?" she gasped.
"The very same thing we could smell in the smog that night; a rather noxious gas," replied Holmes as he rose to his feet. "The by-product formed when-" He broke off, suddenly gasping for breath. The test tube fell from his fingers as he staggered.
Watson caught him as he fell; Irene came to his assistance and they half-carried the fainting detective to the nearest window where he breathed heavily, coughing and gasping for air. After a while the colour returned to his cheeks and his breathing eased as he leaned against the window frame, drawing in great lungfuls of air.
"Holmes, that was very foolish of you!" chided Watson. "What on earth were you trying to achieve? What was that gas?"
"I was proving my hypothesis, and at the same time establishing just how I came to be in the water," replied Holmes, turning slowly to lean upon the windowsill. He held up his thumb, which was black where it had sealed the top of the test tube. "What do you make of that?"
"Why, it's been stained somehow!" exclaimed Watson.
"Indeed. And now I think all the parts of this mystery are beginning to fall into place," replied Holmes as he pushed himself up and returned to the table, retrieving the test tube from the floor. The liquid had spilled upon the rug, leaving a black stain.
"Go on," said Irene. "What was that stuff you added to the silver?"
"All in good time," replied Holmes, setting the test tube back in a rack then turning his attention to the covered dishes upon the tray. "Ah, devilled eggs! Excellent," he remarked, seating himself upon the settee and reaching for a napkin. "I am utterly famished."
Watson and Irene exchanged glances, then moved to join him.