An Essay on Contagious Diseases more particularly on the small-pox, measles, putrid, malignant, and pestilential fevers

In a crisp early‑eighteenth‑century voice, this treatise makes the bewildering world of epidemic illness into clear, logical steps. The author explains why diseases such as small‑pox, measles, and various fevers spread with such ferocity, rooting the discussion in the philosophy of the age while using plain language for physicians and curious readers alike. Opening with a brief preface that notes the urgency of the times, the work promises a systematic look at the invisible particles that move through air and bodies, causing what was then called pestilence.

The heart of the essay lies in numbered propositions that link the size of blood particles to blockages in the circulatory system, drawing on early microscope observations to argue that contagion is both physical and moral. Illustrations of arteries and capillaries accompany explanations of how foreign particles coagulate and erupt into feverish outbreaks. Though grounded in the science of 1721, the reasoning offers a fascinating window into the foundations of modern epidemiology, making it a rewarding listen for anyone interested in the history of medicine.