essential to know their exact size and position and as far as possible even their shape and consistency. This knowledge is urgently required in order that we may answer the questions, can it be removed, and where is it to be looked for? Or again let us consider the acute diseases of the abdomen. A quarter of a century ago all or nearly all of these were fatal: death was assigned to peritonitis: certain drugs were used to relieve symptoms but nothing radical could be done, so peritonitis held the field and was a general expression for many conditions which were not distinguished because their distinction was of no practical importance. But now we know that to use the term peritonitis as describing the disease is about as enlightening as to speak of failure of the heart or cessation of respiration, and we recognise that it is but the late result of many diseases, most of which are curable by operation if the latter be performed promptly and the true starting point of trouble be attacked. Hence surgery has called for the early diagnosis of all the causes of peritonitis and to-day the diagnosis can be made and is made. The extension of our mechanical technique has not only taught us pathology; it has made us learn diagnostic medicine.
Thus then the lines of advance after the elimination of pain and wound infection have been mainly the free exposure of diseased parts, the fuller knowledge gained thereby, and the more prompt and accurate recognition of the early stages of disease. Each factor has reacted upon the other. Each step has called for the next and has made the next more easy; as quickly as the trail is made it is trodden by many feet and in a very few years the jungle has become a network of solid roads from which again new byways are ever opening out.
Lastly, much has been gained in these past years by the education of the public. Some time ago I tried to