The people never felt secure from this calamity.  Sometimes, perhaps, it was brought into the country by a poor sailor, who had caught the infection in foreign parts, and came hither to die, and to be the cause of many deaths.  Sometimes, no doubt, it followed in the train of the pompous governors, when they came over from England.  Sometimes, the disease lay hidden in the cargoes of ships, among silks and brocades, and other costly merchandise, which was imported for the rich people to wear.  And, sometimes, it started up, seemingly of its own accord; and nobody could tell whence it came.  The physician, being called to attend the sick person, would look at him, and say,—­“It is the small pox! let the patient be carried to the hospital.”

And now, this dreadful sickness had shown itself again in Boston.  Cotton Mather was greatly afflicted, for the sake of the whole province.  He had children, too, who were exposed to the danger.  At that very moment, he heard the voice of his youngest son, for whom his heart was moved with apprehension.

“Alas!  I fear for that poor child,” said Cotton Mather to himself.  “What shall I do for my son Samuel?”

Again, he attempted to drive away these thoughts, by taking up the book which he had been reading.  And now, all of a sudden, his attention became fixed.  The book contained a printed letter that an Italian physician had written upon the very subject, about which Cotton Mather was so anxiously meditating.  He ran his eye eagerly over the pages; and, behold! a method was disclosed to him, by which the small pox might be robbed of its worst terrors.  Such a method was known in Greece.  The physicians of Turkey, too, those long-bearded Eastern sages, had been acquainted with it for many years.  The negroes of Africa, ignorant as they were, had likewise practised it, and thus had shown themselves wiser than the white men.

“Of a truth,” ejaculated Cotton Mather, clasping his hands and looking up to Heaven, “it was a merciful Providence that brought this book under mine eye!  I will procure a consultation of physicians, and see whether this wondrous Inoculation may not stay the progress of the Destroyer.”

So he arose from Grandfather’s chair, and went out of the library.  Near the door he met his son Samuel, who seemed downcast and out of spirits.  The boy had heard, probably, that some of his playmates were taken ill with the small pox.  But, as his father looked cheerfully at him, Samuel took courage, trusting that either the wisdom of so learned a minister would find some remedy for the danger, or else that his prayers would secure protection from on high.

Meanwhile, Cotton Mather took his staff and three-cornered hat, and walked about the streets, calling at the houses of all the physicians in Boston.  They were a very wise fraternity; and their huge wigs, and black dresses, and solemn visages, made their wisdom appear even profounder than it was.  One after another, he acquainted them with the discovery which he had hit upon.