𝑾𝒉𝒂𝒕 π’Šπ’” 𝒂 π’”π’•π’π’“π’Ž π’ˆπ’π’‚π’”π’”?
A storm glass (aka chemical weather glass) is a glass tube containing a solution of ammonium chloride, potassium nitrate, camphor, ethanol and water. A variety of crystal shapes were commonly present in this solution, and it was suggested that their quantity and form could predict the weather.

π‘―π’π’˜ 𝒅𝒐𝒆𝒔 𝒕𝒉𝒆 π’„π’“π’šπ’”π’•π’‚π’ π’‡π’π’“π’Ž π’‘π’“π’†π’…π’Šπ’„π’• 𝒕𝒉𝒆 π’˜π’†π’‚π’•π’‰π’†π’“?

  • Clear liquid: clear weather β˜€οΈ
  • Small dot crystals: humid or foggy🌫
  • Star-like crystals on a sunny day: snow🌨
  • Crystals at the bottom: frost❄
  • Threads near the top: windy🌬
  • Cloudy liquid: rain🌧

Noting that the accuracy of these predictions is variable.

𝑾𝒉𝒂𝒕 𝒄𝒂𝒖𝒔𝒆𝒔 𝒕𝒉𝒆 π’„π’‰π’‚π’π’ˆπ’†π’” π’Šπ’ 𝒕𝒉𝒆 π’„π’“π’šπ’”π’•π’‚π’’𝒔 𝒔𝒉𝒂𝒑𝒆?

Early theories held that the chemical blend inside was sensitive to heat, wind, atmospheric pressure, or even electrical charge.
❌However, knowing that most of the storm glasses were hermetically sealed, the theory of atmospheric pressure affecting the crystal form variation was put aside.
❌Also, the idea that crystals respond to electrical charges in the environment around them seemed implausible, since glass is an insulator and not a conductor of electricity.
βœ…Modern studies concluded that only temperature variations affected the solubility of the crystals inside the solution, resulting in various forms and quantities. Many experiments showed that a rapid drop in temperature resulted in a compact mass of feather-like crystals deposited at the bottom of the glass, and a slow decrease in temperature showed tiny crystal stars suspended in the solution.