Even the very early physicians realized that diseases could spread through the air. Droplets and fomites, it was long recognized, could spread infection; and when scientists learned about bacteria, the air-spread of pathogens became particularly meaningful. Now, in the age of jet airplanes and space travel, of atmospheric pollution in a massive degree, the relationship between the air and bacteria or other minute particles is becoming increasingly important and the various sophisticated investigations increasingly significant.
In a highly effective symposium, the British Society for General Microbiology has provided a wealth of information relevant to the newly developing subject of aerobiology. The symposium brought together representatives from many different disciplines—meteorology and engineering, botany, pathology, microbiology.
The different subjects are admirably arranged. First is a section on air movement, discussing the circulation in both troposphere and the lower atmosphere. Then, another chapter in this section discusses, with excellent illustrative photographs, the airstreams