Having been desired by my greatly esteemed friend Dr. William Heberden, F. R. S. one of the principal Physicians of this city, to communicate what account I had of the success of Inoculation in Boston, New-England, I some time since wrote and sent to him the following paper, viz.

About 1753 or 54, the Small-pox made its appearance in Boston, New-England. It had not spread in the town for many years before, so that there were a great number of the inhabitants to have it. At first, endeavours were used to prevent its spreading, by removing the sick, or guarding the houses in which they were; and with the same view Inoculation was forbidden; but when it was found that these endeavours were fruitless, the distemper breaking out in different quarters of the town, and increasing, Inoculation was then permitted.

Upon this, all that inclined to Inoculation for themselves or families hurried into it precipitately, fearing the infection might otherwise be taken in the common way; the numbers inoculated in every neighbourhood spread the infection likewise more speedily among those who did not chuse Inoculation; so that in a few months, the distemper went thro’ the town, and was extinct; and the trade of the town suffered only a short interruption, compar’d with what had been usual in former times, the country people during the seasons of that sickness fearing all intercourse with the town.

It appeared by this account that the deaths of persons inoculated, were more in proportion at this time than had been formerly observed, being something more than one in a hundred. The favourers of Inoculation however would not allow that this was owing to any error in the former accounts, but rather to the Inoculating at this time many unfit subjects, partly through the impatience of people who would not wait the necessary preparation, lest they should take it in the common way; and partly from the importunity of parents prevailing with the Surgeons against their judgement and advice to inoculate weak children, labouring under other disorders; because the parents could not immediately remove them out of the way of the distemper, and thought they would at least stand a better chance by being inoculated, than in taking the infection, as they would probably do, in the common way. The Surgeons and Physicians were also suddenly oppress’d with the great hurry of business, which so hasty and general an Inoculation and spreading of the distemper in the common way must occasion, and probably could not so particularly attend to the circumstances of the patients offered for Inoculation.

Inoculation was first practised in Boston by Dr. Boylstone in 1720. It was not used before in any part of America, and not in Philadelphia till 1730. Some years since, an enquiry was made in Philadelphia of the several Surgeons and Physicians who had practis’d Inoculation, what numbers had been by each inoculated, and what was the success. The result of this enquiry was, that upwards of 800, (I forget the exact number) had been inoculated at different times, and that only four of them had died. If this account was true, as I believe it was, the reason of greater success there than had been found in Boston, where the general loss by Inoculation used to be estimated at about one in 100, may probably be from this circumstance; that in Boston they always keep the distemper out as long as they can, so that when it comes, it finds a greater number of adult subjects than in Philadelphia, where since 1730 it has gone through the town once in four or five years, so that the greatest number of subjects for Inoculation must be under that age.

Notwithstanding the now uncontroverted success of Inoculation, it does not seem to make that progress among the common people in America, which at first was expected. Scruples of conscience weigh with many, concerning the lawfulness of the practice: And if one parent or near relation is against it, the other does not chuse to inoculate a child without free consent of all parties, lest in case of a disastrous event, perpetual blame should follow. These scruples a sensible Clergy may in time remove. The expence of having the operation perform’d by a Surgeon, weighs with others, for that has been pretty high in some parts of America; and where a common tradesman or artificer has a number in his family to have the distemper, it amounts to more money than he can well spare. Many of these, rather than own the true motive for declining Inoculation, join with the scrupulous in the cry against it, and influence others. A small Pamphlet wrote in plain language by some skilful Physician, and publish’d, directing what preparations of the body should be used before the Inoculation of children, what precautions to avoid giving the infection at the same time in the common way, and how the operation is to be performed, the incisions dress’d, the patient treated, and on the appearance of what symptoms a Physician is to be called, &c. might be encouraging parents to inoculate their own children, be a means of removing that objection of the expence, render the practice much more general, and thereby save the lives of thousands.

The Doctor, after perusing and considering the above, humanely took the trouble (tho’ his extensive practice affords him scarce any time to spare) of writing the following Plain Instructions, and generously, at his own private expence, printed a very large impression of them, which was put into my hands to be distributed gratis in America. Not aiming at the praise which however is justly due to such disinterested benevolence, he has omitted his name; but as I thought the advice of a nameless Physician might possibly on that account be less regarded, I have without his knowledge here divulg’d it. And I have prefix’d to his small but valuable work these pages, containing the facts that gave rise to it; because facts generally have, as indeed they ought to have, great weight in persuading to the practice they favour. To these I may also add an account I have been favoured with by Dr. Archer, physician to the Small-pox Hospital here, viz.

By this account it appears, that in the way of Inoculation there has died but one patient in 267, whereas in the common way there had died more than one in four. The mortality indeed in the latter case appears to have been greater than usual, (one in seven, when the distemper is not very favourable, being reckon’d the common loss in towns by the Small-pox, all ages and ranks taken together) but these patients were mostly adults, and were received, it is said, into the Hospital, after great irregularities had been committed. By the Boston account it appears, that, Whites and Blacks taken together, but about one in eleven died in the common way, and the distemper then was therefore reckon’d uncommonly favourable. I have also obtain’d from the Foundling Hospital, (where all the children admitted, that have not had the Small-pox, are inoculated at the age of five years) an account to this time of the success of that practice there, which stands thus, viz.

On the whole, if the chance were only as two to one in favour of the practice among children, would it not be sufficient to induce a tender parent to lay hold of the advantage? But when it is so much greater, as it appears to be by these accounts (in some even as thirty to one) surely parents will no longer refuse to accept and thankfully use a discovery God in his mercy has been pleased to bless mankind with; whereby some check may now be put to the ravages that cruel disease has been accustomed to make, and the human species be again suffered to increase as it did before the Small-pox made its appearance. This increase has indeed been more obstructed by that distemper than is usually imagin’d: For the loss of one in ten thereby is not merely the loss of so many persons, but the accumulated loss of all the children and childrens children the deceased might have had, multiplied by successive generations.