in the English Channel near Brighton. 59 



fully ignited, in order to volatilize the chloride of ammonium, 

 where, however, a dissipation of hydrochloric acid had taken 

 place. 



{Sometimes I found faint traces of oxide of iron, when the 

 concentrated water was mixed with sulphocyanuret of potas- 

 sium, particularly after boisterous weather ; 1 found the same 

 in respect to organic matter. The sea-water taken on a fair 

 and calm day, when very transparent, did not yield the 

 slightest indication of extractive matter when evaporated and 

 ignited. A small quantity of free carbonic acid gas has been 

 likewise found ; and also extremely minute traces of chloride 

 of ammonium were detected, when about 5 pounds of sea- 

 water were evaporated in a water-bath to nearly half an ounce, 

 which, mixed with caustic soda, produced fumes close to a 

 glass rod wetted with hydrochloric acid. 



Sea-water has been likewise examined for silica, alumina, 

 slrontia, manganese, phosphoric acid, and nitric acid, none of 

 which could be detected. 



The sea- water used for the occasion was taken on the 3rd 

 of June, from the surface six miles from the shore, at high 

 water. The weather was fair, the sea calm and extremely 

 transparent. Its specific weight was at 60° Fahr. r0274. 

 Another portion obtained by a proper apparatus from the 

 very bottom of the sea, 10 fathoms deep, was of the same spe- 

 cific gravity, and likewise that taken almost close to the shore. 

 In the month of July, after a previous rainy day, the sea- 

 water taken four miles from the shore, had at 60° Fahr. a 

 specific gravity of r0274; at a distance of 2 miles, 1*0271; 

 and close to the shore, 1*0268. It was examined several 

 times in August, the weather being fair and warm, when the 

 specific gravity amounted to 1*0274'. This appeared to be 

 the greatest weight. 



When weighed in fair weather in December, it was almost 

 1*0271 ; after rain I found it to be 1*0267. These variations 

 will of course depend entirely on the state of the weather. If 

 the atmosphere be bright, and no heavy rain has lately fallen, 

 the water will have, even close to the shore, the same specific 

 weight as out at sea, but after rain it is obvious that the sea- 

 water close to the shore will be most diluted. It is therefore 

 indispensable that the sea-water for examination should be 

 taken at a distance of several miles, that its specific weight 

 should be ascertained, and that the analysis should be per- 

 formed from one and the same dip. 



I cannot conclude this paper without drawing the attention 

 of medical men to the importance which the brine springs on 

 the Continent have lately acquired, as, for instance, the springs 



