James Poulton's account of glue bat printing

Bat printing described by James Poulton, engraver, in the Liverpool Student, 1799.

*Note he calls the medium ‘paper’ throughout, although from his description it is clearly not paper but a bat of glue. Was this a conventional term within the engraving and printing trades?   

Of transferring copper-plate impressions to earthenware

 1/ Of the preparation of the transferring paper*

Take one pound of the best glue, soak for six or eight hours in clean water, wipe its surface clean, put it into a glazed earthenware vessel and add to it half a pound of Barbadoes Tar. Let the vessel be put into boiling water and the ingredients stirred till they are well incorporated. Next pour this mixture of glue and tar into a broad shallow dish to form a cake of about a quarter of an inch thick, and when cool it is fit for use.

 2/ Of the oil for filling the engraved plate

Take one pint of linseed oil, to which add a spoonful of pulverised umber. Let them boil for thirty or forty minutes, and when cold the clear oil may be kept to be used with a little oil of turpentine. If the plate do not clean easily a few drops of Barbadoes Tar must be added to the oil which will cause it to work with ease.

 3/ Of the press

The press is a piece of wood 12 or 14 inches long 9 inches broad and 7 or 8 inches high. The upper part must be rounded evenly and covered with three or four folds of flannel and over them must be neatly fixed a covering of smooth leather.

 4/ Of the boss

The boss is made of a bag of smooth leather filled as much as possible with corded wool or bran. It is generally about 16 inches long and 12 broad.

 5/ Of filling the plate and printing

Take a bit of cotton, roll it into a ball, dip it in the prepared oil, rub the plate all over with the oil. Clean the plate with the hand as in common copper-plate printing. The transferring paper* being cut to the proper size and laid upon the press, the plate must be gently pressed upon it beginning at the nearer end and proceeding gradually to the other. The plate now being taken up, the transfer paper* will adhere to it, which must be carefully separated from it, beginning at one end corner. The transfer paper* is then placed upon the boss and the vessel to be printed pressed gently upon the printed side of the paper*, beginning at one end and proceeding to the other.

The paper* being carefully separated from the vessel, the proper colour ground fine must be dusted on the printed part of the vessel with a piece of cotton wool, which will adhere to the oil left upon the vessel by the transferring paper*. Any loose particles of dust must be wiped off with a handkerchief, and when the work is dry and properly cleaned, the vessel is fired, and the work completed.

 

Details of bat printed decoration, for more information on the complete objects click on the image
sadler

morris

worcester 
 spode