IV

PREFACE.

illuminatiug power of gas, have been particularly noticed ; and to render the work more com-plete, a section on the Arrangements of Gas-works has been added, including an account ofthe Gas-works of the Metropolis, and of the largest and smallest in the provinces, foundedon information contributed by the engineers. These additions to the Work have been madewithout much enlarging its bulk, partly by expunging matter that was obsolete, and partlyby enlarging the size of the pages of letterpress. By these means the present volume hasbeen made to comprise nearly one-third of new matter, illustrated by ten new plates andfifty additional wood-engravings. Compared with the Second Edition, it contains doublethe quantity of letterpress, and three times the number of illustrations, while the publishingprice has been reduced one-third.

To those gentlemen who have kindly assisted in perfecting this Edition, and who have sup-plied drawings and wood-engravings for illustration, the Editor is anxious to express hisgrateful acknowledgments. These are due especially to Mr. T. N. Kirkham, engineer ofthe Imperial Company’s Station at Fulham; to Mr. F. J. Evans, engineer-in-chief of theChartered Company; to Mr. L. W. Pritchard, engineer of the Western Company; to Mr.A. King, of Liverpool; to Mr. Cathels, of Shrewsbury ; to Mr. Bower, of St. Neots; toMr. E. W. Hartley, and to Mr. Sugg, from each of whom he received much valuable infor-mation, with drawings and woodcuts for illustration.

F. C. B.

Hampstead, June, 1866 .