The results of the present-day and popular point of view are appalling. Somewhere about half the cases of cancer are far too advanced for us to think about curing them at the time the patients appear. Of the remaining half, approximately two-thirds have about a thirty per cent. chance of cure, and the remainder about a sixty per cent. chance. These figures are rough estimates based on impressions formed in hospital out-patient work, but they will not be found far wrong. The heart-breaking part of it is that it is all the result of fear, carelessness and crooked thinking, which could be avoided in a large percentage of the cases. Yet there are signs that we are entering on a new phase, and that a realisation of the importance of early diagnosis is slowly permeating through the medical profession. In America we see an increasing insistence on the use of detailed and specialised laboratory methods for exact diagnosis; and in Great Britain there is in existence, at St. Andrew’s University, a complete medical unit, under the supervision of Sir James Mackenzie, for the investigation of the early symptoms of disease. The establishment of this institute is, I think, one of the most important advances that medicine has made in the last twenty-five years, for it is a milestone on the road to progress, a concrete and tangible expression of a changed point of view. Let us for the moment leave generalities and give some few minutes to more detailed consideration of the disease; first in outline, and then in respect of some particular cases. Cancer is a degeneration. It most often occurs at that period of life when our biological work is done, and, as far as Nature is concerned, we are of no use. From _her_ point of view we are on this planet to reproduce our kind and, when we are past doing that, our tissues begin to lose their firm hold on their appointed form, and stray from their former habit of exactly reproducing _their_ kind when attempting to recover from any kind of injury. Cancer is commonest in those organs which have soonest finished their work――the reproductive organs of women; and, after these, it appears most often in that organ so much more abused than any other――the stomach. The greatest number of cases appears at or after fifty, and therefore at that age it behoves us, not to _wait and see_ whether we shall get it or not, but to _look and see_ that we have not got it, for of people who survive till the age of fifty, a great many more than ten per cent. die of cancer. From the biological point of view cancer presents another interesting feature. It used to be generally stated by biologists that acquired characteristics cannot be transmitted. In cancer we see a cell taking on foreign characteristics in response to some environmental stimulus and transmitting these to its offspring until the organism from which it sprang is destroyed.