53 1863 PREFACE. Ir my own experience and reflection had not sufficiently impressed me with the sense of the intrinsic importance of the subject of this treatise, I should have derived it from the contemplation of the many eminent names which are inseparably connected with the history of its literature. When to the strong inducement thus afforded for its prosecution was added the knowledge of the circumstance, that there had not been published a monograph upon it in the English language for upwards of a century, I conceived the hope that a work of that kind might be neither unseasonable nor unwelcome. The main doubts which opposed this hope in my mind had reference to the nature of the elaboration which I should be in a position to give to the matter, so as to ensure novelty and completeness while excluding bulk and diffusion. I have endeavoured to meet these doubts by a conscientious performance. During my literary inquiries I found that most systematic writers were so incorrect in their statements and references, and, not rarely, so unintelligible in their accounts, that it became an essential part of my work to read or consult as many original authors as were accessible to me. The results of these labours have been corrections of numerous mis-statements propagated by compilers, as I could observe in some instances, from one to the other through the long space of two centuries. The necessity of these rectifications, together with the positive results of this search in books, appeared to me to afford some justification of the length of my first chapter. Bearing in mind that Morgagni had almost exhausted the subject of the physical description of gall-stones, I endeavoured to be as short and dogmatic upon that part as the necessity of introducing some new matter on the nature of the nuclei of some calculi permitted. The casts of the biliary ducts which I found in the centre of gall-stones, were represented on two original plates, and their appreciation, by the aid of a fair description and a short discussion, was left to the judgment of the benevolent reader. I then began that part of my work, by which I expected to furnish for my time on the field of chemistry what Morgagni had accomplished for his on the field of physical description; namely, a complete account of the analysis, in gredients, and composition of all varieties of gall-stones of man and animals, together, if possible, with an analysis and explanation of the morbid process to which they owe their origin. This led of course to some new intelligence on various collateral matters, among them perhaps the most interesting being the elucidation of the chemical nature of the colouring matter of bile. More important results were embodied in a new classification of gall-stones, which was immediately used for arranging all analyses of single gallstones to be met with in the books consulted or expressly executed by myself. To the adoption of this arrangement I was moved not only by the contemplation of the requirement of completeness, but also by a wish to assist the probable wants of future inquirers, and to afford to curators of Museums facilities for the practical arrangement of their collections. The somewhat lengthy analyses of a number of ox gall-stones which were submitted to the scrutiny of the Chemical Society, led me to an attempt to explain the origin and nature of gall-stones by the light of the process of the putrefaction of bile; of which also I offered new analyses and an explanatory diagram. Thus I came upon a theory in the true sense of the word; namely, the explanation of the process as derived from all the data on the record, with so much only of hypothesis as seemed justified by the amount of incontrovertible knowledge. The anatomy of gall-stone disease could be described with the aid of such a choice of materials, that the attainment of a fair abstract of the acquisitions of science was fairly to be demanded. To this I added the results of several dissections made by myself, together with the large amount of interesting information obtained by a careful contemplation of the specimens preserved in Museums, particularly in the one which derives from Hunter; illustrating not only the characters of calculi, but also their relations to and effects upon the biliary cyst and passages. histories of cases in the catalogue of this latter collection appeared so instructive and so quaintly original, that I transferred to my text some of them which illustrated peculiar points in the pathology of the disease. The In the description of the symptoms of that episode of the disease generally termed hepatic colic I have been careful to avoid a common fault of authors, which consists in conjecturing a set or series of symptoms as the necessary consequences of particular anatomical conditions, of which the actual vital effects were not directly known by observation. In the description of the symptoms of the passage of gall-stones I have for the same reason exclusively relied upon cases in which the gall-stones were actually obtained and scrutinised by competent persons after the issue of the disorder. By this rigorous process many |