I was recently reading about Admiral Robert FitzRoy's storm glass and how it was used to predict the weather conditions based on the formation of camphor crystals in a sealed glass tube containing distilled water, ethanol, potassium nitrate, ammonium chloride, and camphor.
I started searching for the possible explanations of its working. The first one I encountered stated that it only worked on the changes in atmospheric temperature and was nothing but a thermometer. But there were other articles (like How to Make Fitzroy's Storm Glass) stating that there are also some electromagnetic and quantum (quantum tunneling) explanations for the appearance of crystals and how the atmospheric pressure affects the crystal formation even though the glass tube is SEALED.
I searched for these explanations but couldn't find them. Does anyone have any idea how one can apply the concepts of electromagnetism and quantum tunneling to explain the formation of crystals with the change in weather and how atmospheric pressure might influence the contents of a sealed glass tube.