Excerpt from Typhoid Fever: Its Causation, Transmission and Prevention But the human body is more than a machine; it is an organism Of living cells, each a living entity, and each working for the good of all. Invaded by cells from with out, a mortal struggle takes place within the body. The enemy, though microscopic in size, and fighting with the aid Of insidious toxins, has Often been the victor; but, thanks to the science of bacteriology and its influences in the arts Of healing and Of public sanitation, the terrible ravages Of the infectious diseases known in former days have been checked, and all along the line there has been marked progress in combating the bac terial foes. How great the value of the modern sanitary arts is to the welfare of the human race is seldom realized, yet the vital statistics published year after year are filled with proofs that diseases are gradually lessening and that the span Of human life is lengthening