Parsley, Sage, Rosemary, and Time
The following is from Daniel J. Boorstin's fascinating book The Discoverers: A History of Man's Search to Know His World and Himself.
There seems no end to the desperate ingenuity spent on ways to count the passing hours of the night before inexpensive artificial illumination became universal. After the invention of the mechanical clock the striking hour was the obvious way of conquering darkness. A clever French inventor in the late seventeenth century, M. de Villayer, tried using the sense of taste. He designed a clock so arranged that when he reached for the hour hand at night, it guided him to a small container with a spice inserted in place of numbers, a different spice for each hour of the night. Even when he could not see the clock, he could always taste the time.