Man zählt wie oft die Grille in 25 Sekunden zirpt, dividiert das dann durch drei und addiert 4. So bekommt man die ungefähre Aussentemperatur.
48 x Zirpen ÷ 3 = 16
16 + 4 = 20
Origins: Crickets chirp by rubbing their wings or legs over each other. Yet it is only the males of the species that make this noise — they do so to attract mates. Therefore, when you’re happily listening to the soothing sound of crickets chirping, you’re actually eavesdropping on a courting ritual meant to warn off other lust-filled male crickets and to draw interested females to the ones doing the serenading.
The notion that counting the chirps of crickets can serve as an informal way of working out the temperature is not new — in 1897, physicist Amos Dolbear proposed the reverse of that idea, stating outdoor temperature determined the number of cricket calls one would hear. Over the years, his way of looking at this relationship was turned around — people now count the chirps to get the temp rather than consult the thermometer to figure out how many cricket calls they will hear.