Does odor have weight?

Odor is the name of the sensation produced when certain substances come in contact with the olfactory region. The term is also applied to the collective diminutive particles that produce this sensation. Very little is known about the sense of smell and it is a disputed question whether it depends on a chemical or physical process. The .substances thatproduce the sensation of odor are either in gaseous condition or they are infinitesimal in size. They certainly must have weight, although nobody has yet been able to weigh them. “A non-volatile substance,” says the United States Bureau of Standards, “cannot have an odor, because none of it can get to the nose. As the sensation of odor is caused by minute amounts of the odorous substance reaching the nose, obviously the substance must be evaporating. In other words, it is losing weight, and what reaches the nose has some weight, however little.” The remarkable fineness of the particles producing odor is demonstrated by a simple experiment. Air [ 436 ] conveying odor is filtered through a tube packed with cotton wool and inserted into the nose. Notwithstanding the packed cotton wool, the smell, is.discernible. One scientist estimated that the particles must be less than 1/100,000 of an inch in diameter to pass through the cotton wool packed in the tube. A grain of musk will scent a room for years> and if it is then weighed no appreciable loss of weight can be detected. The smell of camphor can be detected when mixed with water in a proportion of one part of camphor to 400,000 of water. Vanilla is also very pungent and can be recognized when mixed in water in the proportion of one to 10,000,000. Sweetly scented substances that have been in Egyptian tombs for 5,000 years still give off a distinctly discernible scent when the tombs are opened.