Title page of "Exanthematologia: or, an attempt to give a rational account of eruptive fevers, especially of the measles and small pox", Thomas Fuller (1730). The anatomy of the blood detailed includes the "vital spirits", which (according to the author), are made in the lungs and give life and heat to the blood, help to fight infection, and can become excited by activity or stress. Other similar spirits are the "animal spirits", which are formed out of the blood in the brain, and travel through the nerves to perform functions of sense and motion. Infections and "venoms" are explained by the author as tiny particles travelling down to us from the atmosphere or rising up out of the earth. In the second part the author very thoroughly describes a range of fevers, carefully identifying distinct diseases, and making the point that one cannot cause another. Some advice for healthy living to avoid infection is given, including avoiding drunkenness and gluttony, keeping a house clean, and white washing walls. Transmission from an infected person is identified as the most common cause of disease. However, the author also describes several cases where an individual became so worried about the idea of catching smallpox, and thought about it so much, that they developed the disease. A very detailed description of every stage of small pox and methods of treatment is given, including medicines, diet, the patient's environment, and how to judge whether bleeding will help. The appendix at the end discusses inoculation, and gives several case studies of people who have been inoculated using smallpox matter.