During the time that Mr. Bessemer was engaged in studying this question he was informed that the government were themselves cognizant of the fact that they were losers to a great amount annually by the transfer of stamps from old and useless deeds to new skins of parchment, thus making the stamps do duty a second or third time, to the serious loss of the revenue. One official in high position said that he believed they were defrauded in this way to the extent of probably L100,000 per annum. To fully appreciate the importance of this fact, and realize the facility afforded for this species of fraud by the system then in use, it must be understood that the ordinary impressed or embossed stamp, such as is employed on all bills of exchange, if impressed directly on a skin of parchment, would be entirely obliterated by exposing the deed for a few months to a damp atmosphere. The deed would thus appear as if unstamped, and therefore invalid. To prevent this it has been the practice as far back as the reign of Queen Anne to gum a small piece of blue paper on to the parchment; and for still greater security a strip of metal foil is passed through it, and another small piece of paper with the printed initials of the Sovereign is gummed over the loose ends of the foil at the back. The stamp is then impressed on the blue paper, which, unlike parchment, is incapable of losing the impression by exposure to a damp atmosphere. But, practically, it has been found that a little piece of moistened blotting paper applied for a whole night so softens the gum that the two pieces of paper and the slip of foil can be removed from the old deed most easily, and be applied to a new skin of parchment, and thus be made to do duty a second or third time. Thus the expensive stamps on thousands of old deeds of partnership, leases, and other old documents, when no longer of value, offer a rich harvest to those who are dishonest enough to use them. A knowledge of these facts led Mr. Bessemer to fully appreciate the importance of any system of stamps that would effectually prevent so great a loss; nor did he for one moment doubt but that government would amply reward success. After some months of study and experiment, which he cheerfully undertook (although it interfered considerably with the pursuit of regular business, inasmuch as it was necessary to carry on the experiments with the strictest secrecy, and to do all the work himself during the night after his people had left work), he succeeded in making a stamp that satisfied all the necessary conditions. It was impossible to remove it from one deed and transfer it to another. No amount of damp, or even saturation with water, could obliterate it, and it was impossible to take any impression from it capable of producing a duplicate.