We might extend these statistics and references, and quote from the reports of many other distinguished physicians who have been very successful in the treatment of this disease; but these are sufficient for the purpose of directing our inquiries as to the utility and success of different modes of practice. It is immensely important to ascertain, if practicable, the general principle which has been most successful in the treatment of this disease, before it shall again make its appearance among us as a prevailing and fatal epidemic; especially when we realize and duly appreciate its vast mortality, as represented in the report now before us, that prior to its recent irruption and prevalence in India and Europe, nearly fifty millions of the earth's inhabitants have been swept away by this terrible scourge alone. This estimate may, however, appear excessive and unworthy belief. Yet the general average for the forty-three years included is only a little over one million per annum, truly a vast number to be carried off by the prevalence of one disease alone. But, if we reduce this estimate within more reasonable limits, and take only two-fifths of it, or twenty millions, as an approximation to the truth, it would still be appalling, and imperatively demand, on account of the vast interests involved, the most rigid and thorough investigation as to both the direct and indirect cause of this vast sacrifice. It will also furnish us a sufficient apology for attempting a brief review and critical examination of the principles involved in the different modes of practice noticed above, in order to ascertain any failures or errors that may have, in some degree, operated as the indirect cause, in procuring this immense loss of life. All must admit that there are, in respect to the treatment of the cholera, great and palpable failures and errors which, though they have continued for nearly half a century, and have been sanctioned by high authority, as well as by long usage, ought nevertheless to be fully shown and exposed, so that they may henceforth be avoided. In our examination, there is but one rule to be observed, and one criterion of ultimate appeal by which to try each and every principle on which any mode of practice may be conducted. This universal and acknowledged rule is Pathology, the science which unfolds and exhibits the nature and character of disease, and "dictates the maxims of rational practice." It is the foundation and only base of rational medicine, which proceeds on the assumption that the nature and character of disease is fully known and appreciated. This knowledge is not only rational, but indispensable, in order to understand and apply the principles which ought to govern in the medication and cure of disease. CHAPTER IV. SECTION I.--GENERAL PRINCIPLE OF RATIONAL PRACTICE--DICTATED BY THE PATHOLOGY OF THE DISEASE--CONFIRMED BY OBSERVATION AND EXPERIENCE.