1900 ] on Pottery and Plumbism. 411 



form will be released from the obligations imposed by certain rules, 

 and only tbose will be enforced whicb are aimed at the prevention 

 of danger from dust or at securing general cleanliness. 



Leadless glazes have the disadvantage of being less fusible than 

 those containing a relatively large quantity of oxide of lead, and 

 hence require a higher temperature in the glost oven. But it may 

 be doubted, even in this case, whether sufficient regard has been paid 

 to the circumstance that mixtures of silicates melt at a lower 

 temperature than the mean melting-point of their constituents. A 

 properly compounded glaze does not melt as a whole to begin with ; 

 one portion only softens in the outset, and gradually acts as a flux 

 towards the rest. Much, too, depends upon the fineness to which 

 the glazing material has been ground. 



Every intelligent potter will concede that there is an ample field 

 for investigation, by modern methods of attack, on problems con- 

 nected even with the first principles of his art, and that it is not 

 unlikely such investigations would lead to far-reaching results in 

 practice. 



I see little prospect at present that such investigations will be 

 made. The schoolmaster may be abroad among the potters, but the 

 science master, I am afraid, is not. 



Such laboratories as are to be met with in association with works 

 like the Aluminia factory at Copenhagen, or that of Villeroy and Boch 

 at Dresden, are altogether unknown or undreamt-of in Staffordshire. 



There is probably no industry in the world — certainly none in 

 England — which is so conservative in its operations as that of the 

 potter. It is true that the best of English earthenware still enjoys, 

 by common consent, the pre-eminence which the skill and aptitude 

 of Wedgwood and his immediate followers imparted to it. The great 

 potter was fully abreast — as, indeed, his letters to Priestley abun- 

 dantly show — of the physical science of his day, and was quick to 

 test or take advantage of any discovery which seemed to promise to 

 be of service to his art. But, whilst his methods, or some of them, 

 may still be used, it is, perhaps, open to doubt whether the spirit of 

 Wedgwood has altogether descended to his successors, for there can 

 be no question that the exercise of his spirit — that is, the intelligent 

 application of simple chemical principles — would, years ago, have 

 obviated, to a large extent at least, this evil of plumbism among the 

 pottery workers. 



At the conclusion of the lecture Professor Thorpe exhibited 

 numerous specimens of leadless-glazed ware, whicb, through the 

 kindness of several well-known manufacturers, who have adopted the 

 process, had been forwarded to him for the purpose of illustrating 

 his address. 



[T. E. T.] 



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