By too much action in the arterial system, I mean a certain morbid excitement in the arteries, accompanied by preternatural force, which is obvious to the sense of touch. It differs from the morbid excitement of the arteries, which takes place in common inflammatory fevers, in being attended by less febrile heat, and with little or no pain in the head or limbs. The thirst is nearly the same in this state of dropsy, as in inflammatory fevers. I include here those dropsies only in which the whole system is affected by what is called a hydropic diathesis. That debility should, under certain circumstances, dispose to excessive action, and that excessive action should occur in one part of the body, at the same time that debility prevailed in every other, are abundantly evident from the history and phenomena of many diseases. Inflammatory fever, active hæmorrhages, tonic gout, asthma, apoplexy, and palsy, however much they are accompanied by excessive action in the arterial system, are always preceded by original debility, and are always accompanied by obvious debility in every other part of the system. But it has been less observed by physicians that an undue force or excess of action occurs in the arterial system in certain dropsies, and that the same theory which explains the union of predisposing and nearly general debility, with a partial excitement and preternatural action in the arterial system, in the diseases before-mentioned, will explain the symptoms and cure of certain dropsies. That debility predisposes to every state of dropsy, is evident from the history of all the remote and occasional causes which produce them. It will be unnecessary to mention these causes, as they are to be found in all our systems of physic. Nor will it be necessary to mention any proofs of the existence of debility in nearly every part of the body. It is too plain to be denied. I shall only mention the symptoms which indicate a morbid excitement and preternatural action of the arterial system. These are, 1. A _hard_, _full_, and _quick_ pulse. This symptom, I believe, is more common in dropsies than is generally supposed, for many physicians visit and examine patients in these diseases, without feeling the pulse. Dr. Home mentions the _frequency_ of the pulse, in the patients whose cures he has recorded[35], but he takes no notice of its force except in two cases. Dr. Zimmerman, in his account of the dropsy which terminated the life of Frederick II, of Prussia, tells us that he found his pulse _hard_ and _full_. I have repeatedly found it full and hard in every form of dropsy, and more especially in the first stage of the disease. Indeed I have seldom found it otherwise in the beginning of the dropsy of the breast. [35] Medical Facts. 2. _Sizy blood._ This has been taken notice of by many practical writers, and has very justly been ascribed, under certain circumstances of blood-letting, to an excessive action of the vessels upon the blood.