Sodium Hydroxide Bottle This is a clear glass, cork-stoppered bottle of Sodium Hydroxide. It now contains only white powdery residue. It has a white and red paper printed label: “NOT TO BE TAKEN. FANNIN & CO. Ltd. Chemist & Surgical Instrument Makers 41, GRAFTON STREET, DUBLIN.”with “Sodium Hydroxide NaOH n/10" in black handwritingin the blank area. A smaller circular label says “41 GRAFTON ST FANNIN & CO LTD DUBLIN.” Sodium hydroxide (NaOH), also known as caustic soda or lye, is a strong and versatile chemical. It looks like a white solid and dissolves easily in water, creating heat. NaOH is used in many industries, such as making paper, soap, and detergents, treating water, and processing food. It is very alkaline and can neutralise acids, clean surfaces, and help in food preparation. Because it is corrosive, it must be handled carefully with proper safety measures. 1900-1949