Some Observations on the Distribution of Cancer in the Severn Valley

While research on the immediate cause of cancer is being pursued with tireless zeal by many earnest investigators it seems that there is still some work to be done on the nature of what may be termed the secondary or accessory causes, those external or envioronmental factors or conditions which predispose to, or favour the onset of the disease in the presence of the determining cause, whether this be chronic irritation of some kind superadded to an inborn tendency and special suceptibility in the patient or the activity of some micro-organism.