The Darlys advertised that " Ladies to whom the fumes of the Aqua Fortis are Noxious may have their Plates carefully Bit, and proved, and may be attended at their own Houses, and have ev ry necessary instruction in any part of Engraving, Etching, Dry Needle, Metzotinto, etc . . ."
12.
Potential calcination is that brought about by " potential " fire, such as corrosive chemicals; for example, gold was calcined in a reverberatory furnace with alkali salt; copper with salt and sulfur; iron with sal ammoniac and vinegar; tin with antimony; lead with sulfur; and mercury with aqua fortis.
13.
In addition, she was involved in co-ordinating Charles I's attempts to escape captivity, seeking for this purpose guidance from Charles I's execution, provided her with the contact of a locksmith from whom to obtain files and aqua fortis to be used on the window bars of the king's chamber at Carisbrooke Castle, Isle of Wight.
