72 Potassium. — Steam Engines in Cornwall. 



vented any great loss of lives. — Two short papers were also read r 

 One on the ceremonies observed at the coronation of the Colastri 

 Rajah on the Malabar coast, by Mr. Brown ; and another, on 

 several ancient coins struck by the Parthian kings, abont 250 

 years before Christ, and which were presented by Dr. Robinson 

 to the Society. 



XVIII. Intelligence and Miscellaneous Articles. 



POTASSIUM. 



JJY an improved process, this substance may now be obtained 

 in great quantities, and exceedingly pure. A few days ago an 

 experiment was made by a French gentleman, in the laboratory 

 of the Royal Institution, by which abont an ounce ot potassium 

 was obtained from three or four ounces of potash. The appa- 

 ratus employed was a double-recurved gun-barrel, similar to that 

 usually employed ; but connected at one end with a tube of glass 

 descending into an open vessel of mercury, which by the pres- 

 sure of the atmosphere tends to maintain a pressure within, 

 equal to that of the atmosphere. 



STEAM ENGINES IN CORNWALL. 



Messrs. Lean, in their monthly report of work done by steam 

 engines, state, that several counters of engines were idle in De- 

 cember. 



The average work of twenty-five reported was 22,319,663 

 pounds of water lifted one foot high with each bushel of coals. 

 Besides these, the following appear in the report for December. 



Woolf's engine at Wheal Abraham, loaded 1 5*1 per square 

 inch in engine cylinder, lifted 43,383,351 pounds with each 

 bushel . His other engine, at the same mine, loaded 3* 1 per inch, 

 lifted 25,6/5,547 pounds: — his engine at Wheal Vor,loaded 12*1 

 per inch, lifted 35,367,233 pounds : and his engine at Wheal 

 Unity, loaded 13' S per s(iuare inch, lifted 32,0-14,976 pounds 

 one foot high with each bushel. 



The altered engine at Wheal Chance, loaded 13 "4 per inch, 

 lifted 47,048,844 pounds with each bushel. 



Some of our correspondents have asked us why the lightest- 

 loaded engine does the least work with the coals ? They will 

 understand this by asking themselves another question : Suppose 

 the load only one ounce, what would the engine then lift with 

 each bushel ? A certain portion of the coals is consumed in 

 merely keeping the engine in motion — whether it carries the full 

 load or not, 



I}£. 



