The following paragraphs contain the conclusions drawn from this investigation. 1. The rate of attack on the bare metal increases with increasing temperature; particularly in the pickling of black stovepipes steel in 18.3 percent sulfuric acid solution where the rate of attack on the bare metal at 75°F is 0.097 milligrams per square inch per minute, while at 142°F the rate of attack is 0.51 milligrams per square inch per minute. 2. The time required to remove the surface oxide from the sample decreases with increasing temperature. 3. The 18.75 percent phosphoric acid solution removed the most surface oxide in the least amount of time at 165 and 177 °F. 4. The effect of Rodine 50 inhibitor on 20.5 percent hydrochloric acid pickling solution cannot be studied because the rate of attack on the bare metal of uninhibited pickling solution was too small, at 80 °F. 5. The addition of Rodine 82-A inhibitor to a pickling bath containing 18.5 percent sulfuric acid decreased the rate of attack on the bare metal from 0.0858 milligrams per square inch per minute to 0.0286, without appreciably affecting the time required to remove this scale, at 78 °F. 6 No valid conclusions can be made concerning the life of the Rodine 82-A inhibitor because of the erratic nature of the results. / M.S.