1900.] on Pottery and Plumbism. 403 



a simple silicate of lead containing about 70 per cent, of lead oxide ; 

 or it may be as a double or compound silicate of lead, alumina and 

 lime, &c, containing from 20 to 50 per cent., or even more, of oxide 

 of lead. 



There must, of course, be some advantage attending the use of lead 

 compounds in earthenware and soft china glazes, otherwise their 

 employment would not be practically universal. There can be no 

 question that lead glazes do, on the whole, fairly fulfil the properties 

 needed in a glaze. They are transparent and lustrous, have no hurt- 

 ful action on such colour-producing oxides as are used in decoration ; 

 they are sufficiently hard, unless the amount of lead is excessive, and 

 hence stand a reasonable amount of wear ; they are not absolutely 

 unattacked by acids, but provided that the amount of lead is not too 

 large, vinegar and the acids which may be present in food are without 

 any very marked solvent action. Lastly, unless the covering is very 

 thick, or its composition is such as to constitute an injudicious adapt- 

 ation to that of the body, the glazing does not, as a rule, " craze " to 

 an inconvenient extent. To these advantages must be added that of 

 ready fusibility ; hence the " glost oven " may be fired at a relatively 

 low temperature, which means not only economy in time and fuel, but 

 less risk of loss by deformation of the ware. 



Unfortunately, as you have been told, these advantages have been 

 purchased at the cost of a good deal of human suffering, and, as you 

 have learned, of late years the evil of plumbism in the potteries has 

 grown to such an extent as to constitute a grave scandal. The Homo 

 Office, with whom is vested the superintendence of the execution of the 

 Factory and Workshops Acts, has more than once attempted to deal 

 with this evil. A section of the Press has roused the attention of the 

 public to its magnitude, and Parliament has at length intervened and 

 demanded that something shall be done to arrest it. 



About a couple of years ago the Home Secretary determined to in- 

 stitute a special inquiry into the hygienic question involved in the use 

 of lead compounds in pottery processes, with a view of ascertaining — 



(1) How far the danger might be diminished or removed by sub- 

 stituting for the " raw " lead ordinarily used either a less soluble 

 compound of lead or a " leadless " glaze. 



(2) Whether such substitutes lent themselves to the varied 

 practical requirements of the manufacturers. 



(3) What other preventive measures could be adopted. 



From the report, which was made in the spring of last year, and 

 which is printed as a Parliamentary paper, it appears that the workers 

 in all departments of the manufacture in which lead compounds are 

 used, are liable to become, as it is called, " leaded." Among these 

 operatives were the glaze-dippers and their assistants ; those who 

 clean or trim the dipped ware, and those who place it in the glost 

 oven ; majolica paintresses, and others, men and women, engaged in 

 various ways in colouring and decorating the ware with pigments 

 containing lead compounds. 



