“The use of tobacco has become the rule rather than the exception among the grown men of Europe and America and of some parts of Asia. 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 idiosyncrasy 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. To those good results there are, however, exceptions. It sometimes sets up a very strong desire for its excessive use; this often passing into a morbid craving which leads to excess and hurt. Used in such excessive quantity tobacco acts injuriously on the heart, weakens digestion, and causes congestion of the throat as well as hindering mental action. In many people its use tends towards a desire for alcohol as well. I have repeatedly seen persons of a nervous temperament where the two excesses in tobacco and alcohol were linked together. Tobacco, properly used, may, in some cases, undoubtedly be made a mental hygienic.”
Notwithstanding the insufficient scientific data available as to the results of nicotine on mature men, there is a strong belief on the part of numerous physicians and others that its effect is deleterious. There is no diversity of opinion, however, as to the injury wrought by nicotine on the morals, mind, and body of the adolescent boy. Authorities who have given the subject exhaustive investigation and careful thought are unanimous in their conclusions that the use of tobacco in any form before maturity is injurious. Physical deterioration as a result of tobacco and especially of cigarettes has been conclusively demonstrated by measurements and tests of large numbers of young men in colleges, which show beyond question that physical growth is stunted; lung capacity, without which an athlete cannot achieve distinction, is lessened; the nervous system is irritated and the heart action is depressed. The lungs are rendered susceptible to pulmonary and tubercular infection and the mental development of the boy receives a serious check. Such physical and mental influences cannot fail in producing moral defects as well.
Dr. George L. Meylan of Columbia University has compiled some interesting data from his observations of a large number of college students covering the three and one-half or four years of their undergraduate life at age approximately of seventeen to twenty at entrance and twenty-one to twenty-four at graduation. The following instructive table prepared by him shows the age when smokers acquired the habit:
| Age | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| Number | 1 | 0 | 0 | 2 | 0 | 2 | 0 | 11 | 11 | 18 | 30 | 23 | 16 | 0 | 1 |
It will be observed that the largest number of boys contracted the habit at age seventeen, with ages sixteen and eighteen next in point of numbers. Few boys of the one hundred and fifteen observed in the above table began the habit before the fourteenth year, the age near which adolescence begins. Dr. Meylan reached the following conclusions based on many years of medical examination of boys and young men and his experience in teaching hygiene:
“1. All scientists are agreed that the use of tobacco by adolescents is injurious; parents, teachers, and physicians should strive earnestly to warn youths against its use.
“2. There is no scientific evidence that the moderate use of tobacco by healthy mature men produces any beneficial or injurious physical effects that can be measured.
“3. There is an abundance of evidence that tobacco produces injurious effects on (a) certain individuals suffering from various nervous affections; (b) persons with an idiosyncrasy against tobacco; (c) all persons who use it excessively.
“4. It has been shown conclusively in this study and also by Mr. Clarke that the use of tobacco by college students is closely associated with idleness, lack of ambition, lack of application and low scholarship.”
Dr. Jay W. Seaver of Yale University has expressed the following opinion as the result of his examination of thousands of university students: