C 401 ] 



XX r. An /Attempt to determine t/ie definite and simple PrO' 

 portion''^ m which the consiiinent Parts cfunorganic Sub' 

 stantci ire iivited ivith each other. By Jacob Bruze- 

 LIU5. Projetsor of Medicine and Pharmacy, and M.R.A. 

 Stockholm. 



[Continued from p. 346.J 



XIV. Potass. 



A. Separation of the Base of Potass [Potassium] by means 

 of the Electrical Column, 



X HAVE employed in these experiments the same electrical 

 column as in those which have already been published ; it 

 consists of 'i6 pairs of zinc and copper plates soldered to- 

 gether, each ten inches square, and their surface conse- 

 quently containing 100 square inches each. Between the 

 plates were placed pieces of pasteboard, dipped in a satu- 

 rated solution of common salt. 



I was for a lung time in the habit of performing the de- 

 composition in a glass tube, one end of which was closed 

 round a wire of platina, which projected somewhat within 

 it. I poured quicksilver into it, so that it stood above the 

 level of the wire ; and upon this a saturated solutum of 

 caustic potass, containmg some undissolved crystals; I 

 then brouoht the plaiina wire of the positive pole of the 

 column into the alkaline solution, and made a communi- 

 cation between the fixed platina wire of the tube, and the 

 negative pole of the column. While the column was in 

 strong action, that is, commonlv, for the first two days, the 

 potass and the water were decomposed together; but when 

 the action v\as weaker, the potass alone was decomposed. 

 Since in this apparatus the affinity of potassium for oxygen 

 appeared to be weaker than that of hydrogen, I thought 

 that it merely depended on the too great intensity of the 

 dischar-ic, that any water was decomposed by it; and the 

 cause of this intinsity seemed to be the too small dinjen- 

 sions of the discharging surfaces in comparison with those 

 of the columns, and with the quantity of electricity dis- 

 placed. I therefore hoped that an extension of the dis- 

 charge to a greater surface would diminish the intensity, 

 - and thus prevent the decomposition of water, and the con- 

 sequent waste of electricity, and afTord a larger quantity of 

 potassium, since the whole electricity would be confined to 

 this c>bject. According to these ideas, I altered the appara- 

 tus; I poured (piicksilver to the height of about a line into 

 a little di^h ot glass, with a flat bottom, and about two 

 Vol. 41. No. 182. Ji/7ie 1813. Cc inches 



