The iron precipitate was treated with dilute sulphuric acid (ferric chloride is soluble in ether and ferric sulphate is not) and heated to boiling to decompose the iron resinate. The acid when liberated had a strong characteristic aromatic odor. It was extracted with ether in the same manner as the barium acid. This resinous acid is the acid spoken of in this paper as the IRON ACID. The resinous extract left after the removal of the crystalline methysticin is spoken of as the TOTAL RESINS. The resin acids removed by the preliminary shaking out with the various aqueous alkalies are spoken of as the TOTAL FREE ACIDS. _THE VARIOUS METALLIC SALTS OF THE RESINOUS ACIDS._ After obtaining the potassium salts of the acids and having freed the same from the excess of the potassium hydroxide and potassium carbonate, the possibilities of the formation of different metallic salts were tried. The soluble salts of the following metals yielded precipitates:— Manganese Barium Cobalt Silver Mercury Iron Zinc Copper Calcium Lead The following metallic salts gave a complete precipitation:— Silver Iron (ferric) Manganese Since the barium and iron (ferric) salts gave the best means of separation, they were used to separate the resins. _THE TOTAL RESINS._ The total resins were brown in color, thick syrupy consistency and possessed the characteristic odor of the drug. A molecular weight determination was made in the same manner as with the Barium acids, and the following data obtained. Wt. of pipette before 18.7660 Wt. of pipette after 14.7160 Wt. of resin used 4.0500 Temperature before 3.52 Temperature after 3.71 Change in temperature .18 Volume 37 cc. Constant for solvent 3280 Approximate molecular weight 2000 Combustions were made and the following data obtained. Wt. of boat 3.4722 3.4720 Wt. of boat and resin 3.6355 3.6220 Wt. of resin .1633 .1500 Sulphuric acid tube 79.1051 79.3865 Tube plus water 79.2073 79.4770 Water .1022 .0905 Hydrogen equivalent .01136 .01006 KOH bulb 49.4316 50.8720 Bulb plus carbon dioxide 49.8350 51.2430 Carbon dioxide .4034 .3710 Carbon equivalent .12102 .1010 Percent Carbon 67.31% 67.3 Percent Hydrogen 6.9 % 6.7 Percent Oxygen 26.8 % 27.0