Previous communications from this laboratory have described the tanning properties of the gallic acid esters of certain~ ugars.~,~ From an observation of the type compounds that the natural tannins are believed to be, as well as these synthetic materials, there seems to be in every case a pattern consisting of at least two benzene nuclei joined by some type of bridge, and having a suf-ficient number of water solubilizing groups to import to the compound a ...
