The acetic acid, as far as we can ascertain, is produced directly from dextrose without the previous production of alcohol, since the presence of the latter is not shown by its tests at any stage of the fermentation. We have also ascertained that the organism is without action on dilute solutions of alcohol, in yeast water, no acid being produced. We are indebted to Mr. H. S. Shrewsbury for the analysis of some of the gases and volatile acids, and also for the preparation of the diagrams. In conclusion we may state that the investigation of this fermentation in the tannery has been the means of pointing the way to a still more complicated process, viz., “bating.” It may even be possible in the future to place these processes on somewhat the same footing as the accurately understood fermentations in the brewing industry although the difficulties in the way are much greater. CHAPTER XI. BIBLIOGRAPHY. The following short bibliography of works on tanning and the bacteriology of leather manufacture, does not profess to be complete, but is given in the hope that it may prove useful. It includes most of the works consulted or referred to in this book. For particulars of some of the earlier works (Nos. 1, 2, 4, 5, 6, 7, and 8), I am indebted to Dr. E. Stiasny, of Leeds University. Nos. 1–10 are old works on Tanning generally. Nos. 11–57 books and papers referring chiefly to bating and the bacteriology of Leather Manufacture. Nos. 58–78 deal with putrefaction. Nos. 79–133 are general works consulted, in order of date. 1. La Tannerie et la preparation des Cuirs. (MS.) Desbillettes. 1708. 2. L’art du tanneur. De la Lande. 1764. 3. The art of tanning and currying leather, with an account of all the different processes made use of in Europe and Asia for dyeing leather red and yellow, collected and published at the expense of the Dublin Society. To which are added Mr. Philipo’s method of dyeing the Turkey leather as approved of by the Society for the Encouragement of Arts, etc., and for which he had a reward of £100 and their gold medal for the secret. Also the new method of tanning invented by the late David Macbride, M.D., London, reprinted for J. Nourse in the Strand, Bookseller to His Majesty. 1780. 4. Lohgerberei, Ignatz Bautsch. Dresden, 1793. 5. Ueber die Bearbeitung der Tierhäute zu allen Gattungen von Leder. P. J. Kasteleyn. German translation from the Dutch. Leipzig, 1797. 6. Chemisch-technologische Grundsätze der gesammten Ledergerberei. 2 vols. S. F. Hermbstädt. Berlin, 1805 and 1807. 7. Dictionary of Chemistry and Mineralogy. 2 vols. A. and C. R. Aikin, 1807. 8. Hand-Encyclopädie für das Gerben, Zurichten, etc., des Leders, L. F. Kummer, Berlin, 1830. 9. Handbuch der Gesammten Lohgerberei. Vom Dr. Ch. H. Schmidt. Weimar, 1847. 10. Lehrbuch der Sohlledergerberei. Dr. G. W. Bichon, Berlin.