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successful, but yet far from perfect. A second machine was made 

 by Mr. Donkin, and erected, in 1805, atTwowaters, Herts, in which 

 he introduced further improvements, although much still remained 

 to be done. However, in 1810, eighteen of these complex machines 

 had been erected at various mills, some of which are even now at 

 work ; and, at this period, having overcome the practical difficulties, 

 Mr. Donkin erected in this, and various foreign countries, many si- 

 milar machines, which rapidly superseded the method of making paper 

 by hand. Thus for eight years Mr. Donkin gave his time and skill 

 almost wholly to this one object ; and his perseverance was crowned 

 with signal success ; for, although the original idea was not his, 

 the credit of its entire practical development is due to Mr. Donkin. 



The paper machine, of which at this time about two hundred 

 have been made and erected by Mr. Donkin and his sons, ranks 

 amongst the most useful and complete of mechanical contri- 

 vances ; carrying the process uninterruptedly from the liquid pulp 

 to the perfect sheet of paper, ready for writing or printing. The 

 merit of these and of the later improvements introduced by the 

 Messrs. Donkin was recognized by the award of the Council Medal 

 at the Great Exhibition of 1851. 



Mr. Donkin was also one of the earliest to introduce improve- 

 ments in printing machinery. In 1813, he, in conjunction with 

 Mr. Bacon, secured a patent for his Polygonal printing machine ; 

 and one was erected for the Cambridge University. It was then also 

 he invented and first used the composition printing-rollers, by which 

 some of the greatest difficulties hitherto experienced in printing by 

 machines were overcome. 



Mr. Kcenig and Mr. Cowper both used these rollers in their 

 patent printing-machines, with Mr. Donkin's permission, which 

 must be considered an act of the greatest liberality, since without 

 these rollers no such machine can work. With the Polygonal ma- 

 chine, from 800 to 1000 impressions were produced per hour; but it 

 never came into extensive use, as the construction was expensive, 

 while the work produced was of a quality beyond that required in 

 machine printing. 



Mr. Donkin was also much engaged with Sir William Congreve, 

 in 1820, in contriving a method of printing stamps in two colours, 

 with compound plates, for the prevention of forgery ; and, with the 



