Ms. Keaton was often enough able to take the relevant chemical formula and link it mnemonically to the task at hand. So it was not unexpected that every so often a student would ask, "Is there a formula for that?" without considering that if there were one, they wouldn't have to ask.She'd lean her head back slightly and take this slow, hushed breath of a laugh. Her nose would wrinkle and with a gentle flare of the nostrils she'd offer the reply, "You just have to know it."
