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Dr. Apjohn read a paper on the Analysis of the Water 

 of the Dead Sea. 



After some general remarks upon the geographical posi- 

 tion, extent, and depth of the Dead Sea, the geological 

 structure of the surrounding country, and the different 

 statements handed down by the older historians, and to a 

 certain extent corroborated by modern travellers, in refe- 

 rence to the excessive density of its waters, and the absence 

 from them of living things, both animal and vegetable, Dr. Ap- 

 john gave a historical sketch of the analytical researches, in 

 reference to this water, of Lavoisier, Marcet, and Klaproth. 



The specimen which he examined, he stated to have been 

 recently brought to this country by George James Knox, 

 Esq., from Syria, and to have been committed to him for 

 analysis by the Rev. Thomas Knox, both members of the 

 Academy, and authors of valuable scientific communica- 

 tions, read at our meetings, or published in our Transactions. 

 A number of experiments were now detailed, having for 

 their object to determine the nature of the saline consti- 

 tuents of the water, and illustrate its composition and pro- 

 perties. Its specific gravity was set down as 1 153, and its 

 boiling point as 221°. Its contained salts were enumerated 

 as sulphate of lime, chloride of calcium, chloride of magne- 

 sium, bromide of magnesium, chloride of potassium, chloride 

 of sodium, chloride of manganese, and sulphate of lime ; the 

 chloride of potassium and manganese, and the bromide of 

 magnesium having, as he thought, up to the time of the 

 completion of his analysis, been first detected by himself. 

 It held in solution an unusually small amount of air. 



The following is an outline of the method of analysis 

 employed. 



To approximate to the quantity of saline matter, a 

 known weight of the water was evaporated to dryness, and 

 finally heated to about 400°. The residuum amounted to 

 18.91 per cent. 



2b 2 



