Q: What happens when you cross an inorganic chemistry professor bored with scientific papers, a qualitative unknown salt analysis lab, and the public domain?
A: Student engagement.
The Adventure of the Athenaeum Club
It had been some months since quitting my rooms at Baker Street to leave my friend Sherlock Holmes to his long awaited and well deserved retirement. My practice and family commitments demanded the better part of by attention and it became increasingly rare that I should find an afternoon unengaged that I might direct my path to the home of that most singular personality. One such occasion presented itself on a golden day of late autumn, 1900. A changeable September had ceded way to a mild October in which the warm air allowed one to forgive the disappointingly cool, wet summer just past. Following a peaceful turn about the orange-red carpet bequeathed Regent’s Park by its now barren trees I was admitted by Mrs. Hudson into the once familiar flat. I found Holmes perched in his usual chair with his fingertips pressed firmly together and eyelids drooping,
The air hung heavy with an acrid mix of Virginia tobacco and spoiled eggs. Only after giving a cough did Holmes recognise my presence and jumped from his chair to greet me. I returned his kindnesses but admonished him that in his retirement he should pay more attention to his pantry.
“Surely after so many years of chronicling my methods you are not still so stubbornly opposed to applying them yourself!” He rebuffed me. “What eggs should I have used to produce that odour? The remnants of a cold meal remain in full view upon the buffet. Perhaps I turned to this option upon discovery of the spoilage? A more clever deduction, but not one that accounts for the facts as you must know them. From the skins in your teeth and residue on your fingers I know that you have recently consumed a packet of roast nuts, purchased from the vendor near the boating lake in the park, if the leaf on your shoe does not misdirect me. The packet is not in your hand and so was obviously discarded in my refuse bin, but where were the offending eggshells?”
I had to admit his account of my activities was accurate and that I had encountered neither shells nor smells in the bin.
“The smell, which you rightfully though incorrectly associated with rotten eggs is the sulphide gas produced when thioacetamide is introduced to acid, a useful reaction in the investigation of metal cations.”
I had of course known that after doffing the notorious mantle of Britain’s premier consulting detective he had turned his masterful powers of analysis to chemical researches, and indeed upon the table sat a watchglass of some salt, stoppered bottles of vitriol and chlorine acids, and tubes of bright yellow liquid.
“If only that explanation cleared the air as effectively as the phrase suggests.” I said.
Holmes laughed genuinely, if uncharacteristically, at the pun but an introspective wateriness in his eyes hinted that he found more humour in its connection to ideas as yet known only to him.
“Yes, Watson, it is stuffy in here isn’t it? Perhaps you’d care to join me at The Athenaeum. I was planning to spend my evening there.”
I had never known Holmes to be a club man, nor to willingly frequent so prestigious a location as the one he now named, but I affirmed my availability and willingness to accompany him. Though his calculating mind attached only passing value to companionship, I indulge myself in believing he was pleased at the prospect of my company.
We arrived by cab at the classical building on Pall Mall. The Athenaeum Club’s pure white brick and tall Doric columns projected the power and firmness of the Empire while the golden statue of Pallas Athene declared this a bastion of society’s greatest minds and men. I shouldn’t be surprised that Holmes’ name would be listed alongside those of Herbert Spencer, Charles Darwin, and James Bryce as one of the most influential intellectuals of the day. The Sergeant-at-arms gave us a polite nod as we entered the lobby hall and we headed towards one of the richly appointed sitting rooms in the wings.
“You are no doubt wondering at my registration at such a club. In fact, you will not find me on the roll, but it seems they remember the small kindness I paid them by resolving the problem of the double sevens. It will make our remaining here for the evening far easier than I expected.”
“My dear Holmes!” I said aghast. Two gentlemen talking next to a marble Theseus turned their heads at my outburst; I dropped my voice in embarrassment. “You mean to tell me you’re not a member?”
“Naturally not. I much prefer the company at the Diogenes. I did have some doubt of our being permitted entrance, though a confident walk has permitted me unfettered access to more secure houses than this, and with less right of privilege. It was a necessary risk to ensure the capture of our prey.”
“Our prey? I might have guessed there was more to our coming here than the friendly passing of an evening!”
“I imagine you did guess, Watson, but you allowed your reason to be swayed by your senses.”
“Would you care to enlighten me to the target of the chase? Or do you intend to maintain the suspense indefinitely.”
“Only a moment longer, Doctor, if you please. Just a moment.”
Holmes’ dark eyes scanned the ceiling of the chamber and finally lit upon a pair of comfortable chairs by a fireplace along the inner wall. We were seated with glasses of brandy in hand before Holmes saw fit to speak.
“You will no doubt have read the account of the unhappy death of Lord Lansdowne, our late Secretary of State for War.”
“Of course, poor chap. A heart attack at his age is hardly rare, but tragic nevertheless. The calls for impeachment last year over his mishandling of the Boer War must have rattled his nerve, and I suppose the stress of the election campaign overcame his constitution.”
“You have read the public account, then, and believed it. You have parroted the story exactly as the Post wrote it on Wednesday’s front page.”
“Why should I believe otherwise? It is a sound argument, medically speaking, and the examiner in his case is a professional acquaintance and a very thorough pathologist. But for you to ask you must have a different opinion.”
“The examiner saw the falsehoods he was looking for; I saw the truth I am trying to ignore. This is why my retreat from criminal investigation can never be complete; there is simply no one to replace me.” One could not count modesty among Holmes’ few virtues and I bristled at the insult to my colleague. Nevertheless, I had never known Holmes to follow a false trail, so I sipped my brandy in silence.
“The argument is neither sound nor valid, for one who has the facts – and you have more than you think. You read that death occurred in the evening, an unusual time for an infarct though not strange in and of itself. On the fifth page of that same newspaper you might have seen a small report that poor health had kept the First Lord of the Admiralty and the Chancellor of the Exchequer absent from Privy Council chambers for the two days following Lord Lansdowne’s death. The death of one statesman is unremarkable; the illness of three in one evening is, you’ll admit, far more interesting. Once that simple connection is made the rest is elementary. Who can hear of seemingly targeted illness and not consider poison? Who could consider poison and not think of dining? And who could think of these three particular men dining and not arrive at The Athenaeum?”
While I considered the possibility of Holmes’ theory he withdrew a clay pipe, filled the bowl, and sat quietly smoking with his gaze fixed into the fire. Though it seemed fantastic to believe a poisoner could ply their sinister trade so openly without suspicion, he had at least guessed the victims’ dining habits correctly; the Chancellor of the Exchequer himself now joined the party behind us along with Joseph Chamberlain, leader of the Unionist Liberals. Chamberlain’s support for continuing the South Africa campaign was critical to Lord Salisbury’s conservatives’ hope for re-election. If there were political intrigue at play, he would’ve made an attractive target. I attempted to pry further information from my companion, but he had slipped into thought and paid me little attention.
The afternoon passed into evening and besides raising his hand for another glass, Holmes remained still, silently facing the classical stone mantle. The gaslight sconces on the room’s many pillars were raised to push back the encroaching darkness and the yellow glow played shadows about the gilt laurel wreathing the carved marble. The pillars stretched into a high arch whose elongated dome contained a mural depiction of Odysseus’ adventures after the sacking of Troy. I had taken my fill of the ambiance and was about to thank Holmes for a pleasant afternoon and return home when I spotted a prominent Scottish physician with whom I’ve enjoyed a long correspondence. I excused myself from Holmes, though he made no acknowledgement, and crossed the room to re-establish my acquaintance.
No sooner did I greet the gentleman than Holmes leapt from his chair and dashed across the room to fling a platter from the hands of a young waiter. The party nearest stood in outrage – in fact every face in the room was turned now with horrified faces to where Holmes was struggling to remove the server’s jacket. The uproar drew the sergeant-at-arms from the lobby and he pushed his way through the assembling onlookers to the scene.
“Sergeant! Help me! Arrest this lunatic! Let go of my arm, sir!” the waiter shouted, above the murmurs of the crowd.
“Ha! The game is over you scoundrel! Here’s enough proof of your treachery!” said Holmes, pointing to a smear of flour on the man’s sleeve.
The Sergeant-at-arms was unconvinced and demanded to know why a dirty coat deserved such rough treatment. The sentiment was echoed by Chamberlain, the intended recipient of the herring dish now underfoot. In spite of myself I too wondered whether Holmes’ mind had been too long deprived of criminal inquiry and begun inventing conspiracy where there was none. My fears seemed confirmed when he stooped to pick up the knife that had fallen from the tray.
“Sir! Control yourself!” The Sergeant-at arms said as he moved the clam skinned waiter to his rear and the parliamentarians stepped behind their chairs. Holmes wrinkled his brow and scraped some of the flour from the jacket onto the knife.
“I find it incredible that this demonstration is still necessary, but please do observe.”
In saying he raised the knife into the gaslight and it ignited into an unnatural green flame. All but one in the fearful crowd was silenced in wonder.
“Why that is the characteristic colour of barium!” said a white bearded gentleman later identified as Sir Thomas Stevenson, president of the Royal Institute of Chemistry.
“Exactly. In the form of barium carbonate, a rat poison easily confused with flour in a kitchen and, when added to pickling vinegar, evolves carbon dioxide and barium acetate – the poison he used to kill Lord Lansdowne.”
“That is hardly satisfying proof.” Chamberlain said with a steady composure undermined by his defensive position. “How could you have seen the powder on his jacket while faced away and across the room?”
“Naturally I could not. Although it hangs him, it wasn’t the clue that led to action. From that seat the curvature of the ceiling allowed every word uttered in this room to fall upon my ears. Surely I’m not the only one who noticed the raised ‘E’s, the rounded ‘R’s? Dr. Watson, does it not remind you of your days on campaign?”
My Scottish colleague, just returned from Paardeberg, responded for me.
“A South African!”
“A spy?” Chamberlain gasped.
“An assassin!” Holmes said triumphantly.
It was only then that the Sergeant-at-arms looked behind him to the empty air where the waiter had stood. Wide-eyed he raised a cry to capture the man and took off in pursuit along with the more able bodied of the assembly.
I exhaled audibly in relief that Holmes’ mind had not lost its hone through misapplication. Chamberlain, the politicians, and other astounded witnesses pressed towards Holmes who only insisted on the obviousness of the plot. He coolly detached himself from their excited discussion and walked to where Sir Thomas had retaken his seat. Britain’s foremost analytical chemist stood and, smiling, received the outstretched hand of Britain’s foremost analytical mind.
As usual my esteemed companion Dr. Watson has sensationalized what should be a simple but instructive example of deductive reasoning and analytical chemistry. The matter of the accent and coincidence of the offending substance in evidence upon the sleeve closes the matter of the criminal’s discovery, but fails to justify what initially led to my belief that barium acetate was the agent in question. He did make accidental mention of the investigation by describing my chemical apparatus but a more detailed account is in this case appropriate.
A visit to the body of the deceased and refuse bins of the ill yielded a sufficient volume of pickled foods to conclude they had shared some assortment between them. The presence of the acetate ion was clear enough from the smell of vinegar and was quickly confirmed by warming a sample in concentrated sulphuric acid and ethyl alcohol until the fruity odour of ethyl acetate according to the formula:
[CH3COO]–[Na]+ + H2SO4 –> [Na]+[HSO4]– + CH3COOH
CH3COOH + C2H5OH –> CH3COOC2H5 + H2O
Acetate is not itself harmful, but I reasoned could have carried and masked a poisonous companion element. I purified the collected sample into 50g of salt residue and undertook a systematic analysis to qualitatively identify the deadly cation. After dissolving the salt in purified water, the addition of a drop of 6M hydrochloric acid without producing a precipitate removed any suspicion of lead, silver, or mercury. I then alkalized the sample to a pH of 6 with ammonia and added a further three drops of hydrochloric acid and employed thiosulphate to evolve sulphide ions in situ in hopes of capturing the anion in a sulphide, but without success. Other factors of the case had already ruled out arsenic, selenium, cadmium, or bismuth, but this test confirmed they were not responsible for the death.
After transferring the solution to a beaker, I added another three drops of hydrochloric acid, and reduced by boiling to one half volume to ensure the complete removal of hydrogen sulphide, the source of the smell my self-styled chronicler mistook for bad eggs. Next the addition of 0.1g solid ammonium chloride and liquid ammonia in excess could have produced oxides of iron, aluminum, chromium, titanium, or zinc. All admittedly unlikely poisons, but it would have been reckless to rule them out when so simple a test was possible.
A second application of thiosulphate produced a negative result for zinc, cobalt, manganese, or nickel. Finally the addition of 2 mL ammonium carbonate precipitated a carbonate of barium, strontium, or calcium according to the general reaction:
MCl2 + (NH4)2CO3 –> MCO3 + 2NH4Cl
My suspicion of which of the three possible anions I would discover was confirmed by the dissolution of the precipitate in 8 drops of 6M acetic acid and the addition of 5 drops chromic acid. As I expected, barium chromate precipitated from the resulting mixture according to:
Ba2+ + CrO42- –> BaCrO4
Dr. Watson foolishly described the yellow solution and at the very beginning of his account, thus negating any possible mystery for the attentive reader. From the lasting popularity of his memoirs I can only draw unflattering conclusions on the character of his audience. The pale green colour produced by flame test was a dramatic and unnecessary secondary confirmation of the presence of barium, but one which promptly settled the affair, thanks to the distinguished gentleman of the RIC.
Correspondence (concerning chemical analysis only) may be addressed to the undersigned.
Mr. Sherlock Holmes
221b Baker Street
15 November 1900