revalent among cows, and that by
taking the germs of this disease, which was called cow-pox, and putting
them into the blood of human beings, he could produce a mild form of
small-pox, which never assumed a dangerous character, and yet prevented
the person treated from taking the real deadly small-pox.

From this experiment vaccination, as we know it to-day, resulted. The
practice was given this name in France; the word is derived from
_vacca_, the Latin for cow.

Since vaccination became general, the decrease in the rate of deaths
from small-pox has been wonderful, and there has not been one serious
epidemic where the practice has been followed.

Yellow fever is a much worse enemy to all people who live in warm
climates than small-pox. It is a terrible disease, and often kills its
victims in a few hours. All sailors and travellers in southern
countries have to meet with the scourge, the sailors calling it
familiarly "Yellow Jack."

If it is indeed true that by inoculation people can be made proof
against this awful disease, it will be one of the greatest blessings
this wonderful century has given to man.

As we have said, yellow fever visits our southern shores every year,
though happily not often in an epidemic form. The Government has
therefore sent an expert down to the affected districts to discover, if
possible, where this disease comes from, and ascertain the best means of
preventing it.

Dr. John Guiteras was chosen as the best man to send, and he reports
that it is from Cuba that this unwelcome visitor makes its yearly call
on us.

The doctor declares that the sanitary conditions in Cuba are dreadful.
He says that nothing is done to keep the cities clean or healthy. The
drainage in Havana is of the worst possible description, and in times of
epidemic no attempt is made to prevent the spread of disease.

There is such constant communication between Cuba and the United States
that our Government has been obliged to keep three health officers in
the island to report on the state of things and enforce quarantine
regulations when necessary.

Yellow fever breaks out regularly every year in Cuba, and the doctor
declares that it would be an excellent thing for us if the Cubans were
allowed to purchase their freedom under our protection, as we might then
be able to induce them to put their country in a properly healthy
condition, and save ourselves the trouble and cost of yellow-fever
epidemics.

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