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SCIENTIFIC INTELLIGENCE. 



METEOROLOOy. 



1. On the Spontaneous Evolution of Sulphuretted Hydrogen in the 

 Waters of the Western Coasts of Africa and elsewhere. — In the course 

 of a lecture on this subject, delivered at the Royal Institution, by Pro- 

 fessor Daniell, he observed, that it was curious that the impregnation 

 of the waters of Western Africa with this deleterious gas had sO long 

 escaped attention. In water seaward forty miles its presence can be 

 detected ; and it exists in considerable quantity in the Volta, in Lopez 

 Bay, in the Grand Bonny, &c. ; it spreads over an area of 40,000 

 square miles, from about 8° north to 8° south latitude. The origin of 

 this vast accumulation of sulphuretted hydrogen, Mr Daniell attributes, 

 not to volcanic action, not to the decomposition of pyrites, nor to the 

 process of the decay of animal matter, but to the action and reaction 

 of the vegetable matter carried down by the tropical rivers, and the 

 sulphates always more or less present in sea-water. This, moreover, 

 he has proved by experiment. Last winter he placed some fallen leaves 

 in a jar of new river-water ; also a similar proportion in a second jar, 

 with three ounces of salt, and in a third, with a like quantity of the sul- 

 phate of soda — all closely stopped, and a card-board, with acetate of lead, 

 over each. After having been kept three months in a warm closet he ex- 

 amined them. The first emitted the common smell of decayed leaves; the 

 second that of a pleasant conserve ; but the third, no words could con- 

 vey the stinking odour, nauseous beyond all description. This of itself 

 was sufficient to establish the generation of sulphuretted hydrogen ; but 

 further, the usual blackening of the lead of the card-board in this jar 

 only left no doubt on the matter. Wherever, then, sea- water holding 

 sulphates in solution mixes with fresh water and vegetable matter, 

 this gas must be produced, and its effects on animal life are well 

 known. It is a record in Italy, as well as in Essex, that where the 

 sea has been prevented flooding the marshes, that locality, previously- 

 very sickly, had become perfectly salubrious. . To sulphuretted hydro- 

 gen, therefore, Mr Daniell ascribes the dreaded malaria, as also the 

 deadly stinking miasma of Africa, producing languor, nausea, disgust, 

 and death. The jungle-fever of India, also, he thinks attributable to 

 its presence. The soil abounds with sulphates of magnesia and soda ; 

 must not, therefore, quantities of sulphuretted hydrogen be generated 

 in the jungle-swamps ? Besides the direful consequences to the health 

 of man visiting the deadly shores of Africa, this sulphuretted hydrogen 



