A Lesson in Chemistry With Inspector Bruce Read Online Free PDF Page A

swallowed. “The solvent for salt is water.”
    “Excellent.” He smiled, waiting just long enough for her gray-green eyes to spark to life. He returned to the chalkboard. “In the written exam be sure to incorporate the element symbols in your answer, as in ‘the solvent for salt (Na) is water (H 2 O).’”
    He spent the rest of the class going over each component of the major exam, occasionally tossing out a question—feeling out the general competency of the class. Archie checked his pocket watch. The two hours were nearly up. “Now then, are there any subjects in particular you’d like me to cover?” He scanned the room. “Nothing?”
    A hand rose in the back of the room.
    “Yes, Mr. . . . Crawford?”
    “Might you tell us something about your own laboratory, sir?”
    Taken aback, he laughed self-consciously. “I seem to have forgotten to introduce myself properly.” He tossed a lock of hair out of his eyes. “I am director of the crime laboratory for the Criminal Investigations Division of Scotland Yard. A year and a half ago, I was put in charge of developing a forensics program. We employ four chemists and seven technicians at Whitehall, while a smaller group operates a bomb disposal facility south of the Isle of Dogs.” Archie surveyed the number of mouths hanging open. “Any questions?” A waving ocean of arms and hands went up.
    A bright-eyed young man asked first. “Are you after the dynamiters, sir?”
    “Always.”
    “Do you think there will be further attacks on the Underground?” another queried.
    “The anarchists will certainly try. What the public doesn’t hear much about are the plots we’ve managed to thwart. For obvious reasons, we do not reveal much to the press. There are lives at stake, undercover operatives that work for both Special Branch and the Admiralty. For the most part, we want the anarchists to go about their business, unaware of our surveillance.”
    Nearly half the class had their hands up. Archie checked his watch, nodding to a middle-aged student in the rear. “Time for a few more.”
    “Do you work on regular crimes? Robberies and murders and the like?”
    “Combating terrorism is our first priority, but we are often called in on more conventional cases.” Archie briefly discussed a suspicious suicide case the lab had confirmed to be a homicide. “Arsenic poisoning.”
    Several rows of large round eyes caused him to grin. “We are currently conducting research in the areas of smokeless gunpowder and fingerprint identification.” The entire class was on the edge of their seats. “With practice, it is a relatively simple procedure to dust for fingerprints. We have the powders, brushes, and the techniques to develop the prints.”
    Archie looked around at all the bright faces—including hers. “Perhaps we could have a demonstration some afternoon at the close of class?” His suggestion was answered by a number of enthusiastic nods. “In order to study and classify the developed prints, we need to find a way to transfer them to the lab for analysis. As you can well imagine, fingerprints are extremely delicate and easily destroyed. We’re experimenting with a number of techniques. If any of you have any ideas . . .” Nodding a bow, he closed the textbook he held in his hand. “I welcome your thoughts, future chemists.”
    He picked up a stick of chalk. “Pharmaceutical chemistry will be our first section of study, followed by materia medica and pharmacopoeia. We’ll finish up in the lab with practical chemistry. For Thursday you’ll want to brush up on empirical and molecular formulas and how to calculate mass and percentages. While I write your reading assignment on the board, I’d like you each to jot down what you believe are your best and worst subjects—your strengths and weaknesses. Leave the slips of paper with me on your way out.”
    ONE BY ONE, he opened their messages, scribbling notes under each name on the seating chart. Miss Rose