No. XXII.] APPENDIX. 307 



The motive power of the mill is obtained from a turbine, an horizontal 

 water-wheel, new to this country, but much used in Belgium and France. 

 It is applicable to places where the fall is either slight or great. It is 

 reckoned that by this contrivance from 70 to 75 per cent, of the whole force 

 is obtained, while the vertical breast wheel, which would have been required 

 for this situation, would not have afforded more than from 60 to 65 per 

 cent, of the initial power. In using this turbine the quiet state of the 

 water below the mill is not a little remarkable, for instead of the bubble 

 and boil, it is as smooth as at the mill-head. 



The new bank-note has a new water-mark, and the design which has 

 been adopted is attributed to Mrs. Wyndham Portal, who suggested the form 

 of water-mark which has been approved. These alterations in the water- 

 mark constitute an important part of the new note, and the tinting is 

 effected by means of Smith and Brewer's patent an invention which is 

 considered as a valuable addition to the mechanical appliances of paper- 

 making, and was rewarded by a medal at the Great Exhibition of 1851. 

 They have carried out their contrivances in the Bank. The essential part 

 of this process is the use of steel-faced dies, which are engraved with the 

 desired pattern, after which they are hardened, by being heated in leather 

 charcoal, and then suddenly plunged in water. These dies are used with 

 copper or tin forces in a stamping machine, to give an impression upon 

 plates of sheet brass, and these plates when embossed are filed on the back 

 to the requisite proportions, to allow the moisture of the pulp of the paper 

 to pass through the apertures. The different pieces of brass, when struck, 

 filed, and put together at the paper-mill, by Mr. Brewer, form the mould 

 for the paper, and are so arranged that each mould is designed for two pair 

 of notes. 



In practice, great advantages attend the use of this patent. In the 

 first place, identity in the water-mark of the paper is secured, a matter of 

 no small importance when the subject of bank-notes is considered, and 

 moreover it is specially adapted to give gradations of tints, lights, and 

 shades, which, for the first time, has been introduced into the paper of the 

 Bank of England notes. 



If we contrast this elegant and simple method of mould-making with 

 that previously adopted, the difference is sufficiently striking. In a pair of 

 five-pound notes prepared by the old process there are 8 carved borders, 

 32 figures, 168 large waves, and 240 letters, which have all to be separately 

 secured by the finest wire to the waved surface. There are 1056 wires, 

 67,584 twists, and the same repetition where the stout wires are introduced 

 to support the under- surf ace. Therefore with the backing, laying, large 

 waves, figures, letters, and borders, before a pair of moulds are completed 

 there are some hundreds of thousands of stitches, most of which are avoided 

 by the new patent. Moreover, by this multitudinous stitching and sewing 

 the parts were never placed precisely in the same place, and the water- 

 mark was consequently never identical. In this process we may detect 

 principles which are not only valuable to the Bank, but to all public 

 establishments having important documents on paper, as it affords to the 

 public one more test whereby they may readily discover the deceptions of 

 dishonest men. 



For the preparation of the paper, cuttings are selected from the finest 

 pieces of linen of the purest and whitest colour. These are carefully 



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