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long time ago sponges applied to a goitered neck were 

 found to be a somewhat efficient cure. Later, the ashes 

 only of the sponges were used, and finally, an element 

 obtained from these ashes, which was called iodine, from 

 the beautiful violet color of its vapor. We are all more 

 or less familiar with this substance in the form of tincture 

 of iodine, which is a solution of iodine in alcohol, and 

 also with the iodide of potassium, a very potent medicine. 

 Iodine is now obtained from the ashes of sea-weeds which 

 have absorbed it from the sea water, and have stored it 

 away in their tissue. Besides common salt and sodium 

 compounds, we find in sea water chlorides of potassium, 

 calcium, magnesium ; also the sulphates and carbonates 

 of these metals, together with some of the bromides. All 

 these salts make the water of the ocean heavier than com- 

 mon spring or fresh water, and hence its greater buoyant 

 effect upon ships and all swimming bodies. 



Sea water contains considerable gold in solution, and 

 when we find that the ocean is estimated to contain about 

 two million tons of silver, the question arises, could it 

 not in some chemical way be profitably worked as a mine 

 for the precious metals. 



Mr. CHARLES DERBY, formerly of Salem, and for many 

 years a resident of the Sandwich Islands, was present by 

 invitation, and being called upon by the President, gave 

 an interesting sketch of this group of islands ; described 

 the growth of the cocoa-nut, and other plants found grow- 

 ing luxuriantly in that locality. 



The train for Salem being due, the meeting adjourned, 

 after having unanimously adopted the following resolu- 

 tions, proposed by Mr. WHIFFLE : 



Resolved, That the cordial thanks of the Essex Institute 



