POSTSCRIPT.

xi

of the stone, since, if washed with acid of too great a strength, all the delicate lines willdisappear; or, if etched with too weak a solution, there will be a general tendency inthe tints to clog up and become overcharged. Still greater difficulties present them-selves in so attaching the paper upon which the impression is taken to each of thestones, as to cause the successive colours to fall into exactly their proper places, or, intechnical language, to cause the stone to “register” well. Considerable practice is neces-sary before the requisite amount of dexterity can be attained in this respect; and fewbut those who have stood beside the press, and watched its practical manipulation,would give the workman credit for the degree of skill which is essential to a successfulcarrying out of this part of the operation. Where great rapidity is indispensable,these difficulties are materially increased; because, if any colour be too heavily printed,it will take so long to dry that it will for some time be impossible to work off theremaining tints upon the same impression.

The qualities presented by the plates in the present work will, we sincerely believe,do infinitely more honour to the reputation of the lithographic artists engaged in theirproduction than any eulogy which could be pronounced upon their works by the Au-thor. He is, however, personally, glad to have this opportunity of returning his best

thanks to Mr. Francis Bedford , Mr. Sliegii, and Mr. Vinter, gentlemen to whoserefined taste and brilliant powers of execution the illustrations are mainly indebted fortheir artistic excellence. Of the total number no less than one hundred and nine

subjects have been produced by Mr. Bedford and his assistants. Many plates of

great merit have been executed by the artists permanently attached to the establishmentof the Publisher.

It was originally intended to divide the work into thirty-eight parts, each con-taining four plates, to be delivered to the public at intervals of a fortnight. The workwas also issued in five divisions, each comprising eight parts; and, in order to render thesedivisions of equal extent, it was found necessary to increase the number of parts toforty, embracing, in the whole, 160 plates. The first number appeared on the 1st ofOctober, 1851, and the last will have been published on the 7th of March, 1853.

We may add a few details of the printing-office, to show the great extent of thelabour which has been involved in carrying out this publication, and the consequentdifficulties in keeping faith with the public, which have been surmounted by theindefatigable energy and perseverance of the Publisher. The greatest number ofprintings for any one subject has been 14, and the average number 7. The editionprinted has amounted to 1300 copies. Hence, to keep pace with the demand(each colour requiring a separate impression), the printer has had to pull the woikthrough the press no fewer than 18,000 times, on an average, per week, amounting inthe whole period to 1,350,500 pulls, after every one of which the stone requires to becarefully cleaned, and the paper readjusted for “ register.” It may be readily believed