“explanation of odor.  “Odor is particulate,” he had written. The sense of odor is triggered when particulates in the air hit receptors in the nasal passage and are interpreted in the brain. In other words, when you sense a certain odor, you are actually ingesting particulates (solid particles from the object you smell) that cling to the mucous membranes in the nose and give you that sense of odor. When you smell the decay of a dead body, you are actually ingesting particulates of dead flesh into your lungs. Dead flesh clinging to alveoli, the clusters of air sacs in your lungs. Jennifer had been so grossed out by his description that she had called him up and asked specifically about particulates. “Well, Sis (Jerry had always called her ‘Sis’) it’s like this. I don’t ever make coffee in hotels where they keep the coffee pot in the bathroom, and I use airplanes sparingly.” Gross.”