CHEMISTRY — BASKERVIIXE. 137 



solved in cold water, precipitated with oxalic acid, and the oxalate 

 ignited. The oxide thus obtained was of a slightly pinkish color. 

 It was readily soluble in concentrated hydrochloric acid on boiling 

 for about two hours. By evaporating a greater part of the liquid and 

 cooling, very pretty crystals were obtained. They were then recrys- 

 tallized from concentrated hydrochloric acid. Thus two portions of 

 pure chloride were obtained, one of which had been recrystallized 

 seven times and the other ten times. In order to remove the last 

 possible remnant of impurities, the chlorides were dissolved in water, 

 the solution filtered, and precipitated with oxalic acid. The well- 

 washed oxalates were then ignited to the oxide, which was finally 

 obtained as a fine powder nearly white in color. It dissolved readily 

 in boiling concentrated hydrochloric acid. 



The determination of the atomic weight of carolinium was carried 

 out with this chloride solution. In the previous test two pairs of plat- 

 inum crucibles had been used which were about the same weight 

 respectively, so that crucible I could be used as a counterpoise of 

 II, and crucible III as one of IV. Platinum is volatile to some 

 extent at temperatures above 8oo°C. , as shown by Hulett. In order 

 to avoid errors resulting from this source, the two crucibles which 

 were to counterpoise each other were heated at the same time in an 

 electric resistance furnace built especially for this purpose. The 

 shape of the furnace was similar to that placed on the market by 

 Eimer & Amend, of New York. The dimensions of the interior of 

 the furnace were 6}( inches long, 3^3 inches wide, and 3 l A inches deep. 

 By this arrangement the two crucibles could be placed in the furnace 

 at the same time and heated to the same temperature. The furnace 

 was covered with a sheet of platinum. On top of this plates of 

 fireproof material were placed, which were again covered with brick 

 made of similar material. The temperature of the furnace was 

 determined with a le Chatelier pyrometer tube, which was carried 

 into the interior through a hole driven through the covers. Tne 

 platinum crucibles were supported in the furnace by means of plat- 

 inum triangles in a way that prevented them from touching the 

 bottom. 



Although all care was taken to prevent errors by the arrangement 

 described, it was found impossible to obtain a constant weight of 

 the empty crucibles. The two crucibles were heated, at the same 

 time, to 1200 C. for one hour and placed at once in a desiccator 

 containing phosphorus pentoxide. The desiccator was exhausted, 

 and after three-quarters of an hour the crucibles were weighed on a 

 very accurate balance ; but it was found that one crucible after each 



