The smoker may obviate any slight harmful effects of these substances by care. If he is a cigar smoker he must avoid chewing or sucking the butt end of the cigar in which the acqueous solution finally gathers, and he would find it better to smoke long thin cigars which afford a small area behind the burning point for the collection of acqueous vapor and give a better combustion. Judged from these viewpoints the best and most expensive thick cigar is likely to be more harmful than the very worst kind of a cigarette, for although there may be a much smaller percentage of nicotine in the cigar tobacco, a much larger proportion of it may reach the mouth of the smoker through the water produced by combustion, in the case of the cigar than in the case of the cigarette. Every cigar and cigarette smoker should use a holder for the reason stated. The cigarette from the nicotine point of view is the least objectionable form of smoking. In fact expert opinion is recognizing that unless where the smoke is inhaled cigarette smoking if not excessive is probably harmless. It is hard, of course, to kill a popular prejudice, but we have to deal with demonstrated facts not prejudices. In the case of inhalation of cigarette smoke the danger is from carbon monoxide gas and not from nicotine. When the difference of opinion amongst authoritative investigators are discounted their general results will be found to agree very well with the general facts observed by all users of tobacco. What they see is that probably seventy per cent of the adult male population under all conditions and circumstances use tobacco within limits of moderation. They see around them men who have for many years used it, and they do not observe any particular harmful results in the user of tobacco compared with the nonuser. Men as a rule are not more nervous, more subject to heart troubles or age troubles than women, who as a sex, do not use tobacco. Smokers do not deny and never have denied that the abuse of tobacco is harmful. The general view that both scientific investigators and popular observation is able to support is well expressed by Clouston, who is a world known authority on nervous and mental disease. (See _Hygiene of Mind_, 3rd Ed. London, 1906, p. 260.) "If its use is restricted to full grown men, if only good tobacco is used not of too great strength, and if it is not used to excess, then there are no scientific proofs that it has any injurious effects, if there is no idiosyncracy against it.... Speaking generally, it exercises a soothing influence when the nervous system is in any way irritable. It tends to calm and continuous thinking and in many men promotes the digestion of food. "Tobacco, properly used may, in some cases, undoubtedly be made a mental hygienie."