Prof. Horsford's Phosphatic Baking Powder

Providence, RI: Rumford Chemical Works, [1890-1906]. Printed card, very good. 1 card, 12 cm x 8 cm. This card bears the name of Professor Eben Horsford who was among the first to suggest replacing the expensive and imported cream of tartar in baking powder with calcium acid phosphate, which he patented a process to manufacture, creating Prof. Horsford’s Phosphatic Baking Powder (now known as Rumford Baking Powder). On the back of the card, statements are given by Baron Liebig (a founder of organic chemistry) and Dr. M. H. Henry (a prominent New York doctor) endorsing the product and its healthfulness. Some wear in corners