Observations upon experimental philosophy to which is added The description of a new blazing world / written by the thrice noble, illustrious, and excellent princesse, the Duchess of Newcastle.

25. Of the Plague.

IHave heard, that a Gentleman in Italy fancied he had so good a Microscope, that he could see Atomes through it, and could also perceive the Plague; which

he affirmed to be a swarm of living animals, as little as Atomes, which entred into mens bodies, through their mouths, nostrils, ears, &c.

To give my opinion hereof, I must confess, That there are no parts of Nature, how little soever, which are not living and self-moving bodies; nay, every Re∣spiration is of living parts; and therefore the Infection of the Plague, made by the way of respiration, cannot but be of living parts; but that these parts should be a∣nimal Creatures, is very improbable to sense and rea∣son; for if this were so, not onely the Plague, but all other infectious diseases would be produced the same way, and then fruit, or any other surfeiting meat, would prove living Animals: But I am so far from be∣lieving, that the Plague should be living animals, as I do not believe it to be a swarm of living Atomes, fly∣ing up and down in the Air; for if it were thus, then those Atomes would not remain in one place, but in∣fect all the places they passed through; when as yet we observe, that the Plague will often be but in one Town or City of a Kingdom, without spreading any fur∣ther. Neither do I believe (as some others say) that it is always the heat of the Sun, or Air, that causes, or at least increases the Plague; for there are Winter∣plagues, as well as Summer-plagues; and many times the Plague decreases in Summer, when it is hot; and increases in Winter, when it is cold: Besides, the air being generally hot, over all the Country or King∣dom,

would not onely cause the infection in one Town or City, but in all other parts.

Therefore, my opinion is, that as all other diseases are produced several manners or ways, so likewise the Plague; and as they generally do all proceed from the irregularities of corporeal natural motions, so does also the Plague: But since it is often observed, that all bodies are not infected, even in a great Plague; it proves, that the Infection is made by imitation; and as one and the same agent cannot occasion the like effects in every Patient; as for example, Fire in several sorts of Fuels; nay, in one and the same sort; as for example, in Wood; for some wood takes sooner fire, and burns more clearly, and dissolves more sud∣denly then some other; so it is also with the Plague, and with all other diseases, that proceed from an out∣ward Infection; for the exterior agent is not an imme∣diate cause, but onely an occasion that the Patient has such or such motions; and as the imitating motions are stronger or weaker, quicker or flower; so is the breed∣ing of the disease. I will not deny, but there may be such figurative, corporeal motions in the Air or Earth, which may cause infections amongst those animals that live within the compass thereof, and many times the Air or Earth may be infected by Animals; But some particulars not being infected at all, though they be frequently with those that have the Plague; it proves, that the figurative motions of their bodies do not imi∣tate

those motions that make the Plague; when as, if the Air were filled with infectious Atomes, none would escape; nay, they would not onely enter into Men, but Beasts and Birds, &c.

Concerning the Spotted-Plague, it proceeds from a general irregularity of dissolving motions, which cause a general Gangrene of all the body; and to find a cure for this disease, is as difficult, as to find the Philosophers-stone; for though many pretend to cure it, yet none has as yet performed it; what may be done hereafter I know not; but I doubt they will be more able to raise a man from the dead, or renew old age, and change it into youth, then do it.

As for other Diseases, I refer the Reader to my o∣ther Works, especially my Philosophical Opinions; for my design is not now to make a Physical Treatise; and there they will find of the disease called Ague, that its cause is the irregularity of the digestive or conco∣ctive motions, and so of the rest: for in this present work I intended nothing else, but to make reflections upon Experimental Philosophy, and to explain some other Points in Natural Philosophy, for the better un∣derstanding of my own Opinions, which if I have done to the satisfaction of the Reader, I have my aim, and desire no more.