So, whenever you choke at table, you have a right to call down a benediction upon the soul of your long departed ancestor, the lung-fish. However applicable or remote we may regard "the bearin's of this observation," the practical and most undesirable fact confronts us to-day that this crossing and mutual interference of the air and the food-passages is a fertile cause of pneumonia, inasmuch as the germs of this disease have their habitat in the mouth, and are from that lurking-place probably inhaled into the lung, as is also the case with the germs of several milder bronchitic and catarrhal affections. It may be also pointed out that, history apart, our lung-cells at the present day are at another disadvantage as compared with all the other cells of the body, except those of the skin; and that is, that they are in constant contact with air, instead of being submerged in water. Ninety-five per cent of our body-cells are still aquatic in their habits, and marine at that, and can live only saturated with, and bathed in, warm saline solution. Dry them, or even half-dry them, and they die. Even the pavement-cells coating our skin surfaces are practically dead before they reach the air, and are shed off daily in showers. We speak of ourselves as "land animals," but it is only our lungs that are really so. All the rest of the body is still made up of sea creatures. It is little wonder that our lungs should pay the heaviest penalty of our change from the warm and equable sea water to the gusty and changeable air. Even if we have set down the lung as a point of the least resistance in the body, we have by no means thereby explained its diseases. Our point of view has distinctly shifted in this respect within recent years. Twenty years ago pathologists were practically content with tracing a case of illness or death to an inflammation or disease of some particular organ, like the heart, the kidney, the lung, or the stomach. Now, however, we are coming to see that not only may the causation of this heart disease, kidney disease, lung disease, have lain somewhere entirely outside of the heart, kidney, or lung, but that, as a rule, the entire body is affected by the disease, which simply expresses itself more violently, focuses, as it were, in this particular organ. In other words, diseases of definite organs are most commonly the local expressions of general diseases or infections; and this local aggravation of the disease would never have occurred if the general resisting power and vigor of the entire body had not been depressed below par. So that even in guarding against or curing a disease of a particular organ it is necessary to consider and to treat the whole body.