I frequently saw too, at Chambery, a Dominican professor of physic, a good kind of friar, whose name I have forgotten, who often made little chemical experiments which greatly amused me.

In imitation of him, I attempted to make some sympathetic ink, and having for that purpose more than half filled a bottle with quicklime, orpiment, and water, the effervescence immediately became extremely violent; I ran to unstop the bottle, but had not time to effect it, for, during the attempt, it burst in my face like a bomb, and I swallowed so much of the orpiment and lime, that it nearly cost me my life.

I remained blind for six weeks, and by the event of this experiment learned to meddle no more with experimental Chemistry while the elements were unknown to me.
This adventure happened very unluckily for my health, which, for some time past, had been visibly on the decline.

This was rather extraordinary, as I was guilty of no kind of excess; nor could it have been expected from my make, for my chest, being well formed and rather capacious, seemed to give my lungs full liberty to play; yet I was short breathed, felt a very sensible oppression, sighed involuntarily, had palpitations of the heart, and spitting of blood, accompanied with a lingering fever, which I have never since entirely overcome.

How is it possible to fall into such a state in the flower of one's age, without any inward decay, or without having done anything to destroy health?
It is sometimes said, "the sword wears the scabbard," this was truly the case with me: the violence of my passions both kept me alive and hastened my dissolution.