To establish this assertion, it would be necessary to prove that prior to the introduction of vaccination, or rather of revaccination, it was common for nurses to fall victims to the disease. The attempt is not made, and wisely, for failure would be conspicuous. Jenner never recommended vaccination as a protective for nurses. Their general immunity, along with that of physicians, is noted throughout our older medical literature; nor is the reason far to seek. Smallpox is predominantly an affection of the young, and it is no more surprising that a nurse should be proof against it than that she should be proof against measles, whooping cough, or scarlet fever. Nurses occasionally incur these maladies, and they occasionally incur smallpox. If revaccination preserves nurses from smallpox, to which they are exposed in the intensest form, it should much more preserve soldiers, sailors, policemen and postmen, whose exposure is incomparably less intense; yet these servants of the state (as already observed) are as liable to smallpox as their unrevaccinated fellow citizens of correspondent ages. To speak plainly, the selection of a vocation so arduous and repulsive, marks off a smallpox nurse as unimpressionable, and little apt to catch anything. Smallpox, too, is like tobacco: custom fortifies the constitution against its immediate effects. If the atmosphere of a smallpox hospital is endured for a fortnight, it is likely to continue endurable. On the other hand, if a volunteer sickens on probation, she is not reckoned among nurses. Lastly, many nurses have entered hospitals as patients, and have accepted service in default of other occupation. On these grounds, the nurse argument breaks down irretrievably. At first sight, it seems something, but on scrutiny it proves nothing. POCK-MARKED FACES. V.--Another favourite argument for vaccination is the disappearance of pock-marked faces. People say when they were young such faces were common, whilst now they are rare; and demand, What can have wrought the change if not vaccination? A medical man at a public meeting tried to dispose of some statistics adverse to vaccination by saying that statistics could be made to prove anything; and presently went on to relate that when his mother was a girl every third person she met was pock-marked. She had told him so repeatedly, and there was no doubt about her accuracy. Thus statistics in general were untrustworthy, but his mother’s statistic was unquestionable.