At the Pond, Puddle, or Lake

You can’t imagine what’s going on in a single drop of water from a pond or puddle! It’s teeming with life, an invisible hustle and bustle, and the best part is: you can observe it yourself—without a microscope—using the “Laser-Drop-Method” with a laser pointer and a syringe from the hardware store. Microorganisms, green algae, ciliates, copepods, oral mucosa cells, and red blood cells. Bustling videos for scanning included. How to make light refraction and reflection visible? This can be done with ordinary soap bubbles that turn into disco balls. For the cold season, frozen lakes offer a real “experimental playground”. With a laser pointer, ice floes turn into light organs and the ice thickness of a body of water can also be measured with a laser pointer. The classic must not be missing: The sounds on a frozen lake. Why this is so, you will find out in this chapter.