Additional security was also sought in legislation; advantage being taken by Mr. Timm, the Solicitor to the Stamp Office, of a bill then preparing on postal affairs, to introduce a clause enabling the Postmaster-General to open any letter bearing a forged stamp, or a stamp used for the second time; but as the Chancellor of the Exchequer felt sure that Parliament would not grant such a power, the clause, very much to Mr. Timm’s regret and my own, was struck out. We were, therefore, thrown back upon chemical and mechanical means of defence. It soon appeared that these must be put into further requisition, Mr. Donovan, a chemist of Dublin, having succeeded in removing the effacing black mark without injuring the stamp below. The stamp, it must be remembered, had been impressed by powerful machinery, and likewise had had time to dry; while the obliteration was produced only by hand, and remained fresh. Again, therefore, I had to call in Mr. Phillips. He came accompanied by Dr. Clark, Professor of Chemistry in the University of Aberdeen, who had kindly volunteered his services, and who suggested a number of experiments, which Mr. Phillips undertook to try. On the same day, however, Mr. Phillips reported favourably of a new kind of ink devised by a Mr. Parsons, informing me, nevertheless, that it had yet to be subjected to various tests. At this juncture came a formal report from the Post Office, stating that the red ink was found to be removable, and asking for instructions. The statement, though necessarily made as a matter of form, came to me as a mere truism; but the request for instructions was more easily made than complied with; for about the same time Mr. Parsons’ ink yielded to the skill of Messrs. Perkins and Co., contractors for the supply of adhesive stamps; who, however, reported in turn, that they had prepared two other kinds of ink, either of which they thought would answer the purpose. I lost no time in setting Mr. Phillips to work on the subject; and, in my anxiety, went so far as to trouble the greatest chemist of the age. Kindly giving me the needful attention, though in an extremely depressed state of health, the result of excessive labour—a fact, of course, unknown to me when I made my application—Mr. Faraday approved of the course which I submitted to him, viz., that an aqueous ink should be used, both for the stamps and for obliteration, so soon as the stock of stamps now on hand should be exhausted, and that, in the mean time, obliteration should be made with black printing-ink. As the stock of covers was so large that, considering its little favour with the public, it was likely to last some years; and as, in dealing with those, an oleaginous effacing ink was indispensable, while, nevertheless, it would be impracticable to have two kinds of effacing ink in use at the same time, it was important to procure a destructible oleaginous ink to be used meanwhile in printing the adhesive stamps. I accordingly requested Mr.