In the plague of Vicenza, in a poor family of six per sons, two only took the disease,•although the whole lived in constant and free communication. A similar case occurred to Massaria, in his own house. In Marseilles, the two commissioners who were incredulous respecting the contagion, and Deidier, who believed in it, communi cated freely with the patients, as in ordinary diseases, even to the opening of the bodies after death, and without in jury ; this being one of the circumstances which confirm ed the belief of many respecting the noncontagious nature of the plague. The same happened to the curate, the surgeon, and the notary, in one of the villages ; even though the latter had lost two sons by the disease, whom he was obliged to carry to the grave on his back. A more remarkable instance was that of a child, which was placed in the coffin with its dead mother, with the expectation that it must die at any rate ; yet, being afterwards removed, it did not take the disease, and lived. Many instances of the same kind .occurrocl in the French Egyptian army, even among husbands, wives, and children, but we need not detail more of them.
No reasonable conjectures have been offered respecting these predisposing or indisposing causes ; but the facts themselves serve to confirm our doubts of the efficacy of all the pretended preventatives for this disorder. It will be' proper, however, to inquire into some of the collateral cir cumstances which attend the propagative inactivity of the disease, and the reverse.
It was already seen, that, in Egypt, the disease sudden ly ceased when the hot south winds ceased, and the north winds began to blow. It is also remarkable in this coun try, that the inhabitants of Matwrieh, situated on the margin of water, are nearly exempt from the plague ; a fact, however, which applies to the endemic rather than to the communicated disorder. As to this latter, daily experience seems to prove, that the state and temperature of the air have no effect on it, or at least very little. To the instance of Constantinople, we may add, that it raged in Russia during the most severe cold ; nor, in Marseilles, did it cease, as was expected, during the heats of sum mer. It is thus an important point to make the distinction in this case between the endemic and the communicated disease.
It is generally thought that fear assists in the propaga tion of the plague, as in that of all contagious diseases. It may certainly, in timid persons, render a slight attack fatal ; it may even facilitate the reception of the contagion. But it is a great and fatal mistake, on the other hand, to imagine that it may be braved with impunity, or that fear is necessary to its propagation, as the reverse of this is ex perienced every day.
It is also thought that old persons, from the dryness of their skins, are less susceptible of the plague, and that its reception is facilitated by the use of the warm bath. Wa ter-carriers, or persons much exposed to cold, have been said to be comparatively free from it ; and it is also thought that, among the working classes, it attacks most readily bakers, cooks, smiths, and others, subject to violent heat and changes of temperature.
It has been supposed that the free use of wine was a preventative. Tbis notion is as old as the plague of Athens, yet it has been decidedly opposed by Desgenettes, and others, who farther say, that drunkards are particu larly susceptible of it, and that with them it is always fatal. Certain chronic diseases, issues, the lees venerea, and the itch, have also been thought to ward off this poison ; but that these, on the contrary, facilitate its ravages, is deci dedly asserted by the French physicians employed in Egypt. Respecting the power of the small-pox in this respect, there is some doubt ; as strong instances in its favour are given ; but we have great hesitation in believ ing that the vaccine infection, as has beel asserted, is a preservative against the plague.
On the Practical Prevention of the Plague.
Of preventative medicinal practices, it has already been seen that we entertain strong doubts. Bleeding has been supposed a means of prevention, as has the exhibition of various medicines that must be considered trifling, or ab solutely inert. The most effectual precaution is flight, or seclusion ; and, after that, the cautiously avoiding con tact with infected persons, or infected objects, or with any thing which is even suspected. The use of water we already noticed. For those who are employed about the sick, it is recommended to keep a fearless mind, fully oc cupied in the business ; to touch no body, even in the streets ; never to sit down in a house ; not to stay a mo ment longer near the sick than is•necessary ; to avoid their breath, and to dip the fingers in water after feeling the pulses ; to change the clothes outside the house in return ing, and to cause them to be washed or ventilated ; to wash all the body at the same time ; and lastly, to avoid all in temperance, fatigue, or other debilitating causes, and to live well.
Much has been said of frictions with oil, or of the ex ternal use of this substance, as a preservation against the plague. It is said that those who are employed as carriers of oil in Alexandria and Tunis, always escape. They are so convinced of its efficacy, that they will not lay aside their oily clothes during the continuance of the pestilence, and when this has happened, or that they have cleaned themselves in the warm bath, they have taken the in fection like others. It was also remarked in Marseilles, that tanners, carriers, soap makers, and others accustomed to handle oily substances, were least infected with the dis ease. In opposition to this, it must be stated, that, in the plague of Malta, in 1812, this practice was tried without success; and that, were the remedy as efficacious as has been said, the Armenians, Jews, Greeks, and others, who, in the plague countries, do not believe in predestination, would undoubtedly have recourse to ir. We must think that this is a very doubtful preservative indeed.