In 1818 Edward Cowper, a printer of Nelson Square, patented certain improvements in printing, these improvements consisting of a better distribution of the ink and a better plan for conveying the sheets from the cylinders. Having joined his brother-in-law, Augustus Applegarth, they proceeded to make certain alterations in Kœnig's machine in Bensley's office which at one stroke removed forty wheels, and greatly simplified the inking arrangements. In 1827 they jointly invented a four-cylinder machine, which Applegarth erected for the _Times_. The distinctive features of this machine were its ability to print both sides of a sheet at once, its admirable inking apparatus, and great acceleration of speed, the new machine being capable of printing five thousand copies per hour. These machines at once superseded the Kœnig, and were to be found in use in all parts of the country for printing newspapers until quite lately. In 1848 the same firm constructed an eight-cylinder vertical machine, which was one of the sights of the Great Exhibition of 1851. Shortly afterwards Messrs. Hoe, of New York, made further improvements in the mechanism, raising the output to 20,000 per hour. All these machines had to be fed with paper by hand, but in 1869 it occurred to Mr. J. C. Macdonald, the manager of the _Times_, and Mr. J. C. Calverley, the chief engineer of the same office, that much saving of labour would result if paper could be manufactured in continuous rolls; and the result of their experiments was the rotary press, which was named after Mr. John Walter, the fourth of that name, then at the head of the _Times_ proprietorship. Since then the improvement in printing machines has steadily continued, and may be said to have culminated in the Hoe 'double supplement' press in use at the present day in many newspaper offices, which is capable of printing, cutting, and folding 24,000 copies per hour of a full-sized newspaper. These great changes in presses and press-work have occasioned similar changes in type-founding.