Myths
Smugglers have long believed that substances such as coffee grounds, garlic, peanut butter, etc, will hide the scent of drugs from the canines. This is wrong. Barry uses the analogy of a pot of stew to demonstrate the ability of a dog to detect substances. When humans see a pot of stew they see carrots, potatoes, beef and onions, but we only smell stew. A dog has comparatively poor vision. They see a pot with varying contrast of grey but they smell the separate scents of each individual ingredient in the stew. They smell carrots, potatoes, etc.
Another myth is that air tight containers will defeat a dog's sensitive nose. Barry points out that all materials are permeable to some degree. The longer a substance sits in a container, the more likely its scent will permeate through the container. He uses the example of a dog picking up the scent of marijuana which was sealed in PVC tube and hidden in the gas tank of a vehicle. The dog cannot smell through steel, through gas and then through the PVC tube, but if the marijuana sits in that gas tank for long enough, the dogs will pick up the scent because small atoms of marijuana will eventually permeate through all of those barriers.
