Pierre Bayen (7 February 1725–14 February 1798) was a French chemist (apothecary). He analysed the mineral waters consumed in the Kingdom of France and incorrectly concluded that drinking from pewter vessels rendered the water toxic.
After his studies he began a career in the military that spanned more than forty years.
12Tourneux, Maurice (1901). "Un projet d'encouragement aux lettres et aux sciences sous Louis XVI". Revue d'Histoire littéraire de la France. 2 (2): 281–311. JSTOR40517914.