In the darkroom we often need to add minute drops of liquid to a solution. If you need to measure drops, get a pediatric dropper at the local pharmacy. It's easy to use, accurate, an inexpensive. Here's how to measure small quantities of liquids: 17 drops equals 1 ml; 5 ml equals 1 teaspoon; 6 teaspoons equals 1 ounce or 30 ml equals 1 ounce; 3 teaspoons equal one tablespoon. This space-age device also works in the kitchen!