~18.~ The hand of a man or boy who uses tobacco often becomes so
unsteady that he can scarcely write. Do you know what makes it so
unsteady? It is because the cells which send nerves to the muscles of
the hand are diseased. When a person has a trembling hand you say he is
nervous. If you feel his pulse you will find that it does not beat
steadily and regularly as it ought to do. The heart is nervous and
trembles just the same as the muscles do. This shows that the tobacco
has poisoned the cells in the brain which regulate the heart.

~19.~ Wise physicians will tell you that one reason why tobacco is bad
for boys is that it hurts their brains so that they cannot learn well,
and do not become as useful and successful men as they might be.

~20.~ Students in the naval and military schools of this country are not
allowed to use tobacco on account of its bad effects upon the mind. In
France the use of tobacco is forbidden to all students in the public
schools.

~21. Tobacco Leads to Vice.~--Boys who use tobacco are more liable to
get into company with boys who have other bad habits, and so are apt to
become bad in many other ways. The use of tobacco often makes men want
strong drink, and thus leads to drunkenness. If you wish to grow up with
a steady hand, a strong heart, and a good character you will never touch
tobacco.

~22. Effects of Tea and Coffee on the Nerves.~--People who use strong
tea and coffee are often inclined to be nervous. This shows that strong
tea and coffee, like alcohol and tobacco, are very injurious to the
nerves.