ABSTRACT
I. INTRODUCTION Awareness of the health effects of airborne agents is almost as old as written history. In Western civilization, suggestion of unhealthy "air" is mentioned in the early books of the Bible (Leviticus 14:35-48) and among ancient Roman writings. Blackley (1) provided perhaps the first modern treatise on aerobiology when he presumed that "bronchial catarrh" was due to emanations from freshly cut hay. Pasteur's classic experiments on genu theory compared microbial growths in sterile broths that were either exposed to or protected from air. Although it was not directed toward aerobiology, airborne spores made the experiment work. Airborne material was considered a disease agent long before it was possible to sample the air for biological particles. Gregory's treatise (2) is an excellent additional source on, and indeed a salient part of, aerobiology history.
