314 Improvements on Brunner's process for Potassium. 



in a bottle, replete with hydrogen desiccated by chloride of calcium. 

 I have constructed an apparatus, by which I expect this method of 

 operating will be rendered more easy and effectual, but I have not as 

 yet put it into operation. 



Notwithstanding its unusuafty large calibre the cylinder became re- 

 peatedly so clogged by the metal, and the carbonaceous deposit, as 

 to occasion some difficulty in keeping the passage clear ; and like- 

 wise some loss of potassium, of which a considerable quantity always 

 accompanied the rod used for the purpose when retracted. In or- 

 der to remedy these evils, as a substitute for the iron cylinder above 

 mentioned, I have had another equally long receiver forged, of which 

 the bore at each orifice is two inches in diameter but enlarges at a 

 little distance from either end to two and a half inches. I hope that 

 the cavity of this receiver will be adequate to receive all the conden- 

 sible products without being obstructed. 



I intend hereafter to furnish a more complete description of my 

 process for potassium, illustrated by a cut. 



I have made an improvement in the art of luting. It consists in 

 using the shreds of iron, which are shaved off in making weavers' 

 reeds of that material. These shreds are entangled together like the 

 fibres of wool and constitute a mass which, by analogy, we have call- 

 ed iron wool. With these shreds fire clay blended with as much 

 sand as is consistent with the necessary plasticity is intimately inter- 

 mingled and stamped into a flat cake of a size sufficient to envelope 

 the bottle completely. Being applied to the bottle, it is afterwards 

 secured by a wire wound about it in a spiral, of which the rounds 

 are not more than a half inch asunder, and the ends are duly secured 

 by twisting them together. 



The effect of this intermixture of iron fibres is surprising. The 

 lute hardens on exposure to the fire without previous desiccation. 



I rolled up two equal balls, one, consisting of fire clay alone, the 

 other of the same clay intermingled with the iron wool. Both were 

 thrown into an intensely heated part of an anthracite fire. The ball 

 which consisted of clay alone, soon flew to pieces, while the other re- 

 tained its shape and hardened into a mass having the firmness of a brick. 



The plan proposed by Dr. Gale of keeping potassium in glass 

 without naphtha, is one which I have pursued since 1818. I have 

 been accustomed to seal a tube at one end, then to heat it at a con- 

 venient distance from the end, and reduce the diameter by drawing 

 it down to about a quarter of an inch. Into the tube thus prepared, 

 hydrogen is made to enter, so as to exclude the air. The potassi- 



