Vaccination prevents smallpox in more than 90 per cent. of the exposures to the disease. The death-rate was 58 per cent. in the unvaccinated cases and 16 per cent. in the vaccinated in a group of 5000 cases of smallpox studied by Welch in 1894. During the eighteenth century, according to Bernouilli's calculation, one-twelfth of all the children born succumbed to this disease. In 1707, in Iceland, 18,000 of the entire population of 50,000 died of smallpox. As late as 1885, 3164 persons died of the disease in Montreal in one epidemic brought on at a time when vaccination had been neglected. In Prussia, from 1851 to 1860, without compulsory vaccination for civilians, there were 36,577 deaths from smallpox; in the Prussian army during the same time, with compulsory vaccination, there were only fourteen deaths. During the war of 1870 the French armies, without vaccination, lost 23,469 men from smallpox; the German armies lost only 459 men and there was a great epidemic of the disease in Germany at the time. The efficiency and necessity of vaccination against smallpox, which is as virulent now as it ever was, is so certainly established that a parent or guardian who neglects or refuses to have children vaccinated when exposed to the disease is guilty of homicide through neglect if an unvaccinated child under his care dies of smallpox. Revaccination is necessary every eighth year if smallpox reappears. Agitation against vaccination is not mere ignorance: it is a dangerous crime, exactly like loosing a mad dog; and it is combined with the insolence of ignorance. Persons who have seen smallpox are very much afraid of it, because it is one of the most dreadful afflictions humanity is exposed to; those who have not seen it, yet say they are not afraid of it, are mere fools. A pregnant woman who is infected with smallpox should receive the last sacraments as soon as possible. If she aborts she may die very quickly in collapse. If she is evidently in _articulo mortis_ and the fetal heart can be heard, her cervix should be forcibly dilated, the child turned, and delivered for baptism. If the physician waits for death, the child will be dead also, and sectional delivery will be too late for any good.