2 Prof. Daniell on Sulphuretted Hydrogen 



The first idea which occurred to me was that which seems 

 generally to have prevailed upon similar occasions, viz. that 

 this gas was generated from some change which had taken 

 place in the water after it had been bottled, from the decom- 

 position of some animal or vegetable substance; but a little 

 consideration showed that this explanation was quite inadmis- 

 sible, inasmuch as the sediment from the whole bottle did not 

 exceed half a grain, the water being perfectly bright, and the 

 salts upon evaporation snow-white', and the water became per- 

 fectly sweet a very short time after it had been exposed to the 

 air. 



Indeed the common prejudice regarding the unlimited quan- 

 tity of sulphuretted hydrogen generated by putrescence is per- 

 fectly untenable, and is founded solely upon its disagreeable 

 odour. The fact is, that the quantity of sulphur in animal 

 matter is very small, and the nauseous smell is by no means 

 an infallible criterion of the existence of the gas. 



As a natural product, sulphuretted hydrogen has hitherto 

 been known chiefly as an ingredient in certain mineral waters, 

 such as those of Harrowgate and Aix la Chapelle ; the former 

 of which contains, per gallon, 18*4 cub. in., the latter 44 , 0. 

 The comparatively small springs which yield these waters are 

 most carefully preserved by their proprietors, on account of 

 their medicinal virtues, and the profits which are derived from 

 their use. 



The generation of the gas with which such waters are im- 

 pregnated, has been usually attributed to some unknown action 

 upon pyrites and other sulphurets of the metals in the interior 

 of the earth, and it is pretty generally ascribed to volcanic 

 action. It has also been generally known that sulphuretted 

 hydrogen is produced by processes of decay or fermentation, in 

 which large quantities of animal matters are concerned. 



To the natural sources of this gas must now be added the 

 estuaries of many large rivers and immense tracts of the Ocean 

 in their immediate vicinity. 



The results of the analysis of the African waters, sent to me 

 from the Admiralty, embracing an extent of fifteen or sixteen 

 degrees of latitude, are as follows : — 



Each bottle was properly corked and sealed, and contained 

 about three imperial pints; the water in all was perfectly 

 bright, and had deposited very little sediment. 



The first which I examined was labelled, " Water from the 

 river at Sierra Leone, taken at three miles from the mouth, 

 by Her Majesty's brigantine Dolphin, at low water, spring 

 tides, on the 24th day of September, 1839, during the rainy 

 season. (Signed) " Edward Holland, Lieut.-Com." 



