It was towards the end of 1839 that Mr. Henry Cole visited Messrs. Perkins, Bacon & Co., then at Fleet Street, and told them that the idea of the authorities was that the adhesive labels should be about one square inch in size, and on December 3, 1839, that firm submitted their first estimate of not exceeding eightpence per thousand, nor less than sixpence per thousand, the price being exclusive of paper. The process by which they were to be produced is the now well-known system known as the "Perkins mill and die" process, a method of production which was adopted in due course, and has never been superseded for the production of artistic stamps. The history of the making of the stamp, the combination of the art of Wyon, Corbould, and Heath, I have dealt with elsewhere, so I turn to the envelope plan. Stamped covers, as we have seen, had been used in Sardinia in 1818 and, in a different fashion, in Paris as early as 1653. In 1838, while Britain was in the throes of the postal agitation, New South Wales actually issued and used embossed envelopes, which were sold in Sydney at 1s. 3d. per dozen sheets. The embossed design consisted of the royal coat of arms of William IV. enclosed in a circular frame, bearing the words "General Post Office--New South Wales." [Illustration: THE ADDRESS SIDE OF THE MODEL LETTER WHICH HAS THE STAMP (SHOWN BELOW) AFFIXED TO THE BACK AS A SEAL.] [Illustration: ANOTHER OF THE UNPUBLISHED ESSAYS SUBMITTED IN THE COMPETITION OF 1839 FOR THE PENNY POSTAGE PLAN. (_From the Author's Collection._)] The envelope proposals that were before the Treasury in 1839 consisted mainly of rough sketches, but in a few cases of elaborate printed designs (_e.g._, Harwood's envelope), and the patterns made up of intricate geometrical work like the specimens in Ashurst's "Facts and Reasons" and the "Ninth Report." Cole called upon Mr. William Mulready and invited him to draw a design for the envelope, and it was decided that this design should be printed on the paper with the silk threads embedded in its substance, a paper which has since been known to philatelists as "Dickinson" paper, after the name of its inventor. Mr. Dickinson had all along been keenly interested in the proposals for postage reform, and was a witness before the Select Committee in 1837, providing paper with threads in it for the essays in the Report. Many of the chief officials and the agitators were convinced of the protection that this paper offered against forgery, and it is not generally known--I mention it as specimens of the paper are by no means commonly met with--that Mr. Dilke was so convinced of the importance of the use of this paper that he printed the entire issue of _The Athenæum_ for April 28, 1838, on the thread paper.[7] Mr. Dickinson's firm was at that time supplying the regular _Athenæum_ paper.