I may, perhaps, be doing a chance service to many persons of the better classes, who nowadays more than ever have occasion to write promissory notes and other business documents, if I here copy out for them the receipt for this ink which vanishes after it is dry; I take it from a reliable source. Let the man of rank scrape off the surface from a piece of fine black cloth, such as he wears at court--grind the scrapings finer still on a piece of marble--moisten this fine cloth dust repeatedly with water, then make his ink with this, and write his promissory note with it; he will find that, as soon as the moisture has evaporated, every letter of the promissory note has flown away with it in the form of dust; the white star will have shone out, as it were, through the blackness of the ink. But I consider that I am doing an equal service to the holders and presenters of such promissory notes as to the drawers of them, inasmuch as, for the future, they will be careful not to be satisfied with a security of this description, till they have exposed it for some time to the sun. Some time ago, I should have here been apt to confound this cloth ink with the _sympathetic_ ink (likewise possessing the property of turning pale and disappearing after a time), which is commonly made use of in both the preliminary and final treaties entered into between royal persons; the latter however, has a _red_ tint. A treaty of peace of three years' standing is no longer legible to a man in the prime of life, because the _red_ ink--the _encaustum_, with which formerly no one but the Roman emperors might write--is too apt to turn _pale_, unless a sufficient number of human beings (from whom, as from the cochineal insect, this dye stuff is prepared) have been made use of in its manufacture; and this (from motives of sordid parsimony) is not always the case. So that the treaty has frequently to be engraved and etched into the territory afresh with good instruments--the so-called "instruments of peace"--at the point of the bayonet.