The Chemical Adventures of Sherlock Holmes A Christmas Story Thomas G. Waddell and Thomas R. Rybolt University of Tennessee at Chattanooga, Chattanooga. TN 37403 The followingChristmas story provides a problemin qualitative chemical analysis, presented in mystery form in the context of the popular and beloved characters Sherlock Holmes and Dr. WatThere is a hreakin the story where the reader (studentsand teachers) can ponder and solve the mystery. Sherlock Halmes delivers his solution in the paragraphs followingthis break. The Story I rememberfondly nlcepinfilnteon that Christmas mominn near the turn of the century. Fresh snow had fallen the night before and Holmes and I had stayed up past midnight by the fire, smoking our briars, and recalling the many adventures and dilemmas which other Decembers had brought our way. Overcome by a sense of peace and wellbeing, I slept long and awoke to the sound of carriages muffled by the deep snow and a few cheerful voices ofpeople hurrying along Baker Street beneath my window. The air was cold and the sky was a tone of clear blue seldom seen in the Great Citv. " 1 ~. u l l e dmv dressinz.. gown ., around me. selected a favorite pipe, and went out to the living quarters of 221B to share Christmas with mv friend and colleaeue Mr. Sherlock Holmes. Holmes was in his chair by the crackling fire, humming some tune that sounded operatic, and concentrating the rest of his energy on repairing the fmish on his precious violin. For several weeks he had beeuso engaged, wmplaining of difficultieshe had enwuntered in producing a certain quality color-tone in the varnish, and ignoring my urgings and pleas to attend the new play that had opened at Covent Garden. "Holmes!" I cried. "What a morning!" But I could tell that progress on his violin had stalled and, since no new case occupied his thoughts, he was in one of his sullen moods, totally unacceptable in my mind, even for Holmes, on a morning like this. Holmes did not speak to me, and, when Mrs. Hudson knocked on our door and entered carrying a gift, wrapped smartly in bright red paper, Holmes raised only an eyebrow. "A gift for you, Watson, from an admirer no doubt", he said. "No, Mr. Holmes", Mrs. Hudson shook her head. "It's for you! I found it on the step this morning, 'Mr. Sherlock Holmes, Merry Christmas'the tag says." Holmes put the violin down and took the package fmm the outstretched arms of our fsithful landlady. Since I had been associated with him, only on the most rare occasions had Holmes ever received a gift of any kind, and indeed, he reacted with concern and a grim look of suspicion. He set the red package before him on the floor, glanced a t the tag, and with utmost care untied the ribbon and slipped off the wrapping paper. All this was done without agitating the giR, as it sat before us now in a plain brown box the size of an ale mug.
-
'Waddell, T. G.; Rybolt, T. R. J. Chem. Educ. 1989, 66,981. 'Waddell, T. G.;Rybolt T. R. J. Chem. Ed=. 1990, 67,1007.
A bead of sweat mlled down Holmes'long forehead a s he removed from the box a clear unlabeled jar containing a dry white solid. "Watson", he looked up at me, "recall the names of our most recent foes." "Holmes", I replied, " this is only a gift. It is Christmas, my good fellow. Someone has honored you with a token of their esteem." "Names, Watson", he sternly countered snapping his fingers impatiently. 'The unusual angle and unevenness of the tag's lettering is not characteristic of a natural handwriting. It is clear the person who is the source of this gift is attempting to disguise his true identity. Who might benefit by revenge served up to us in the season of cheer?" "Well, Holmes, there's always Moriarty. But its seems to me that Porlanto the embezzler, Gladson the poisoner, or Kilburn, the one who murdered his stepchildren, are more likely suspects at this time." "Capital!" Holmes rubbed his hands together and carried the iar to his chemical research table in the darkened corner of our flat. As Mrs. Hudson and I celebrated Christmas Dav alone with a masted eoose and three varieties of her famous pies, Holmes work;ed feverishly. We heard an occasional grunt or exclamation from the comer accompanied by the accustomed clank of glassware and shuffling of equipment. At 10:30 Christmas night, Holmes reappeared. I expected a look of triumph, since on other occasions, Holmes' chemical researches always led to startling revelations. This time, however, a look of confusion shadowed his hawklike features. "The substance is easily puritied by sublimation, Watson. It is heat stable and definitely not an explosive. Moreover, I waxed our little mouse friend from his hole by laying out some ham covered with the material. He devoured it, Watson, and I observed him scampering about all day, with no ill effects. Thus, it is not a toxin or a drug either! If this is a n act of revenge, does the perpetrator expect me to sprinkle his poison into my own porridge? There are dark waters here. Watson. sinister anddark waters." ! it as such", I said, showing my "1t;s a giR, ~ o l m e sAccept impatience for his annoying lack of Christmas spirit. Sherlock Holmes turned and paced, ignoring my appeal. "I have measured a melting point of 118-120 "Celsius and i t turns litmus from blue to red. It is decidedly a carbon compound, but of what type and of what purpose is not clear. However, I can say with a great deal of confidence that i t contains 68.8% carbon and 4.9% hydrogen by weight." I reolied gentlv. "There is an hour of Christmas left. Join Mrs. ~ u d s o nan2 me in a celebration of this holy season." I felt the same kindness toward him that I alwavs had. But Holmes is always Holmes, thank God. "In du; time, my friend, in due t i e " , he said "I have one more observation to make and I will have part of this mystery solved." He disa~oearedagain. and this time Mrs. Hudson and I waited bGhc hearth. ~ h c s t o l elittlesad glances at meover the rimsofherrrlassesand I, inan ever-swellinr!Christmas spirit, was becoming more amused as time and as I Volume 68 Number 12 December 1991
1023
reflected on the character of the World's Greatest Consulting Detective. Without a sound, Holmes appeared behind my chair. "A water insoluble organic compound, soluble in alkali", he somberly stated. After making this strange announcement he strode arroeantlv to the window and looked out over Baker Street an2 thegas lamps glowing under caps of snow. He stared into the night for what seemed a n endless time, but when he fmally moved, I pulled out my pocket watch and found only ten minutes had passed. He strode to the dusty corner of the room and returned a moment later with a flask in his left hand and a spatula containing a small quantity of the mysterious carbon compound in his right hand. "If my suspicions are correct, the addition of this compound should result in the evolution of gas from this solution of bicarbonate of sodium. He poured the white powder into the colorless liquid in the flask. As he swirled the flask, he looked directly a t me. Stop Here and Solve the Mystery This mystery can be solved by applying chemical principles and deductions. Can you answer these questions? (1) What organic compound was given to Holmes? (2) Who eave the comoaund to Holmes? I3 For u hat purpose urns the compound given? The following
p a r a ~ ~ a p hamtmn i Holmes'~chemlcal svluuun ur the mystery. Compare your solution to his.
The Solution Mrs. Hudson and I remained seated. mesmerized bv the tiny bubbles rising in the flask. Suddenly he turned and pointed a long white fmger. "You, Watson, yon!" he shouted. 'You are the perpetrator!" Mrs. Hudsongasped with horror. "Mr. Holmes!" she cried. "Have pity a t Christmas time. Have you lost all reason?" Holmes's eves were mere slits andhis brow was furrowed and he kept pointing a t me. Unlike Mrs. Hudson, I was not shocked. I was, on the contrary, quite overcome with laughter. As I was so engaged, Holmes stomped around the flat howling with unrelentina frustration. But after a few minutes h e began to calm down a s I knew be would, and he approached us sheepishly. After another minute or two he chuckled like the gentle old friend he was. "Ah, Watson. When I discovered that the Christmas substance was neither a n explosive nor a poison, the mystery took on a new slant. Was revenge the motive? If so, how? If not, what was the purpose of the white substance? Its identification was then crucial, and, fortunately, a trivial matter of standard qualitative organic analysis. "The substance is clearly benzoic acid, Watson. You knew it as well a s I do now. How vour usual oDen countenance hid your involvement is truly amazing to me." "Well. Holmes". I smiled. "With vow tirade I hardlv had a chance to stop you and before t
