In years past much experimental work has been done, many surveys made, an infinite number of types of treatment advocated and countless words written about the common cold. In spite of all this, far too little is known about its mechanism and satisfactory methods of treatment. The importance of this disease is tremendous. If the common cold could be eliminated, its complications would all be wiped out. Otitis media, mastoiditis, sinusitis, some types of pneumonia and all the serious sequelae of these complications would no longer be feared by patient or physician. Constitutional diseases secondary to some of the infections of the upper respiratory tract would become as rare as typhoid. Since the common cold accounts for about 70 per cent of all infections of the respiratory tract, the economic effect itself deserves attention. It has been estimated1 that the total wage loss per annum to industry in the United