Processes for Potassium. 61 



the receiver, and thus a great portion of metal is lost in the redistilla- 

 tion ; besides, the receiver is sjd large that it is exceedingly difficult 

 to manage in separating it from the retort, for the purpose of redis- 

 tillation, unless it has previously cooled, at least, considerably below 

 redness. A third objection, greater than either of the others, is, that 

 much less metal is obtained by this process, than when the materials 

 are detached by means of the naphtha and iron scraper,* previous 

 to the redistillation. 



To obviate these objections as far as possible, I ordered to be made 

 a thick wrought iron cylindrical bottle, in form, like that of the quick- 

 silver botde, holding a little more than a pint, beer measure. In one 

 end of this bottle, to be used as a receiver, was bored a hole an inch 

 and a half in diameter for receiving the connecting tube d, (see the 

 figure,) which is three inches long, and in the opposite end, another 

 hole was bored half an inch in diameter, for receiving the safety 

 tube. A tolerably correct idea of this apparatus may be obtained by 

 examining the annexed figure, in which 

 is represented a side view of a section 

 of the furnace containing the apparatus 5 

 a, a, passage for the air coming from a 

 room below; 6, h, interior of the furnace ; 

 c, the retort in its place ; d, the connect- 

 ing tube ; e, the receiver ; h, the safety 

 tube ; i, glass cup containing spirits of 

 turpentine ; g, grate with its prop ; f, the 



hook for pulling down the grate when the operation is finished ; Te, 

 the tube to be attached to the receiver e, in redistillation ; I, iron plug 

 to be used also in redistillation. 



With this apparatus I was enabled to keep up the operation, unin- 

 terruptedly, until all the metal had distilled over. This being done, 

 1 proceeded to distill the contents of the receiver without detaching 

 them, by unscrewing the connecting tube from the receiver and 

 supplying its place by the tube k ; the safety tube was also un- 

 screwed, and its place supplied by the iron plug I. The receiver 

 was now coated, and placed horizontally in the furnace, with the 

 tube k, projecting in front, and a little inclined. The heat which had 

 considerably diminished, was raised by additional fuel, until the bottle 

 was heated nearly to whiteness, before any signs of metal appeared. 



* A good one may be formed of a slifif iron rod, flattened at the end, and bent 

 in the form of a scraper; the same is made more durable of steel. 



