"In the case of the liver, which is commonly considered, when in a scirrhous or enlarged state, to be the seat of these mechanical obstructions, and thus, to be the cause of abdominal dropsy, we have no satisfactory instance yet shown to us, of any such precise condition of that organ. There are, indeed, numerous instances of abdominal dropsies, in those labouring under a scirrhous or enlarged state of the liver; but there are also, numerous examples of such states of the liver, as well as of the spleen and other organs, without any such effusion; and in many cases, when such effusion has taken place, it has been carried off by the natural passages or by tapping, without any return of the dropsy; and yet, without any visible change in the structural condition of the liver." Dr. A. further remarks, that if the cause were mechanical and existed in the liver, the effect should be constant; which, however, is not the case. Besides, were this mechanical cause necessary, how could we account for the appearance of abdominal dropsy, where there is no disease of the liver, or in other cavities, where no mechanical cause is asserted to be present, and where the remedies by which the cure is effected, have no relation to such causes? Again, if the discharge depended upon a mechanical cause, the water should in every case be of a uniform fluidity, and the progress of its accumulation likewise uniform; so that the operation of tapping should have no tendency to induce a more rapid refilling of the cavity. Yet, the contrary of all this is a subject of daily observation. In addition to this, Dr. A. calls the attention to the fact, that in experiments, in which obstruction has been artificially made, by tying the vena cava for example, the experimenter has committed an error, in reasoning from the lower animal to man--assuming, that as ascites had arisen in dogs, it would in like manner have occurred in human subjects.