303 



Marduk Baladan, is said to have held Babylon twelve years, 

 which is the exact time that the Canon gives to Mardokempa- 

 dus, the predecessor of Arkianus. After this he was driven 

 to Chaldea. Dr. Hincks maintains that his father, Yagin, the 

 Yugasus of the Canon, was also the father of Sargon, and that 

 having conquered Assyria, he left it to Sargon, while his an- 

 cient kingdom of Chaldea was assigned to Marduk Baladan. 

 On this supposition he accounts for the cancelled inscriptions 

 on the reverse of the pavements, in which the title of King of 

 Babylon, borne by most other kings of Assyria, is omitted. 



Alexander Mac Donnell, Esq., communicated, through Dr. 

 Apjohn, a notice on the results of certain experiments insti- 

 tuted by him for fixing the atomic weight of magnesium. 



In experimenting on the true atomic weight of magne- 

 sium, the method which I used was to find the exact compo- 

 sition of sulphate of magnesia, a salt whose formula is known 

 with certainty to be Mg O, S 3 + 7 H O, and which admits 

 of being rendered perfectly anhydrous without losing any of 

 its acid. 



Some of the crystallized salt was deprived of all hygrome- 

 tric moisture by placing it in the vicinity of a dish of oil of 

 vitriol under the receiver of an air-pump. The water of crys- 

 tallization being then expelled by a low red heat, the compo- 

 sition of the crystallized salt was found to be — 



Water, 51.17 51.13 51.14 51.26 51.28 51.29 



Sulphate of Magnesia, 48.83 48.87 48.86 48.74 48.72 48.71 



100 100 100 100 100 100 

 The sulphuric acid was then precipitated from the anhydrous 

 salt with chloride of barium. The sulphuric acid calculated 

 from the sulphate of barites thus formed showed the composi- 

 tion of the anhydrous salt to be — 



Sulphuric acid, 



Magnesia, 



100 100 100 100 100 



66.67 



66.73 



66.64 



66.65 



66.69 



33.33 



33.27 



33.36 



33.35 



33.31 



