Toronto, Canada: Carter, Cummings, & Co., c1920. An advertisement for Al-Caroid, which was an antacid containing the vegetable digestive ferment caroid. One side of the ad has a color illustration depicting the antacid being mixed into a class of water, with the caption "flavor unusually pleasing, no sickly alkaline taste". The mediation supposedly helped with gastric distress, cyclic vomiting, morning sickness, hyperacidity, sour stomach, and flatulence. At the base of the ad are instructions for use and two color illustrations of the antacid in a cans. The other side of the ad depicts a women in black & white, and states "Litmus paper red often means Danger Ahead in many disorders." The ad was asking women to check the PH of their urine using litmus paper, and if it turned red, it might be caused by or a sign of "diabetes, arthritis, pregnancy, dermatoses, common cold, kidney disorders, or pre and post operative acidosis." In order to fix this one could take a teaspoon every two or three hours until the litmus paper was no longer turning red in one's urine. Single page, double sided. Measures 10 3/4" by 3 1/2" General wear. Crease folds.