LONGEVITY: THE MEANS OF PROLONGING LIFE AFTER MIDDLE AGE. WHAT IS THE NATURAL OR NORMAL DURATION OF HUMAN LIFE? To attain to a lengthened life, to enjoy ease and tranquillity in life's decline, and immunity from pain, debility, and other forms of suffering, are objects worthy of far more earnest attention than they usually receive. At the dawn of modern science, when the properties of natural bodies began to be observed, men sought to find the philosopher's stone, and an elixir vitæ, hoping to preserve life for ever, or at least for a long and indefinite period, and to obtain wealth by a short and easy process. Since we have more accurately investigated the constitution of man, body and mind, the conditions of life, health, disease and death, the nature B and relations of things around us, we are able to form more rational aims, and to pursue them with better hopes of success. How to evade the causes of disease, to obviate their effects when they touch us, how to reach the utmost extent of the term allotted to human existence are legitimate objects of research. And since the most subtle and most tremendous physical forces are made subservient to our daily wants, and the composition and interaction of the materials of our earth, animate and inanimate, are to some extent ascertained and utilised, surely we may expect that means and appliances should be attainable to preserve and prolong human life, to render longevity the rule for many, and not, as now, the exceptional lot of a few. In this line of thought a question emerges which we must meet and answer in limine. How long can men live if exempted or protected from all the influences tending to extinguish life prematurely? What is the term, if any, which Divine Providence has affixed to the duration of human life? As an obvious fact, numbers reach the age of |