There are few things in the history of mankind more extraordinary than the frightful extent to which the crime of secret poisoning was carried, in several countries of Europe, during a large portion of the seventeenth century. It appears to have taken its rise in Italy, where it prevailed to a degree that is almost incredible. The instrument chiefly used in its perpetration was a liquid called _aqua tofana_, from the name of Tofania, its inventor, a woman who has acquired an infamous celebrity. According to the account of Hoffmann, the famous physician, this woman confessed that she had used this liquid in poisoning above six hundred persons; and Gmelin says that more people were destroyed by it than by the plague, which had raged for some time before it came into use. This crime also prevailed, though for a shorter time and to a smaller extent, in France; and was far from being unknown in England. We intend to give our readers such information as we have collected on this curious subject; and though the most regular way might be to begin with the Signora Tofania herself, and the diffusion of her practices in her own country, we prefer giving at present the history of the most eminent of her followers, the Marchioness de Brinvillier, whose atrocities created so much excitement in France in the time of Louis the Fourteenth, as we shall thus be enabled at once to place the matter in its most striking light. We have consulted, we believe, most of the French works in which there are any particulars respecting this lady; and our readers may take the following as a faithful account of her life. Marie-Marguerite d'Aubray was the daughter of M. d'Aubray, a gentleman who held a considerable judicial office in Paris. In 1651 she married the Marquis de Brinvillier. The match was a suitable one, both in respect to station and property. The marquis had estates of thirty thousand livres a-year; and his wife, who had two brothers and a sister, brought him a fortune of two hundred thousand livres, with the prospect of a considerable share of her father's inheritance. The marchioness enjoyed the gifts of nature as well as of fortune. Her figure was not remarkably handsome, but her face was round and pretty, with a serene and quiet expression; and she had an air of innocence, simplicity, and good-nature which gained the confidence of everybody who had any intercourse with her. The Marquis de Brinvillier was colonel of a regiment of foot. While on service, he had contracted an intimacy with a gentleman of the name of St. Croix, a captain of cavalry. There was some mystery about this man's birth. It was known that he was from Montauban. Some thought him an illegitimate scion of a noble house; others said he belonged to a respectable family; but all agreed that he was totally destitute of the gifts of fortune.