§ 155. Notice to be posted. No person shall engage in the sale of adulterated turpentine, adulterated linseed oil or adulterated boiled linseed oil, in original packages or other than original packages, unless there are posted conspicuously in the room where such goods are sold, signs bearing the words "Adulterated Turpentine sold here," or "Adulterated Linseed Oil sold here," as the case may be, in legible letters in the English language at least two inches in length and one inch in width, said letters to be in black on a white background.