On the Distribution oj Manganese. 273 



seen at some points on the Merimac River, and indee^ m ^nK>8t 

 every rivulet in New England. 



I have also noticed similar depositions between the divisional 

 strata planes of sandstones in the valley of the Connecticut, thus 

 shewing, that apparently the same agencies were at work during the 

 deposition of these rock* as at the present day. 



2. On the existence of Organic Matter in Stalactites and Stalag- 

 mites^ forming Crystallised and Amorphous Crenate of Lime, 



In the eighth chapter of Liebig's Agricultural Chemistry, edited 

 by Playfair, there is given the result of some examinations of stalac- 

 tites, from caverns in Germany, and from the vaults of old castles 

 upon the Rhine, made with the view of ascertaining the fact of the 

 presence or absence of organic matter in these bodies, either com- 

 bined or uncombined. 



The result may be stated in the words of the author, Professor 

 Liebig. The stalactites from the caverns '* contain no trace of 

 vegetable matter, and no humic acid, and may be heated to redness 

 without becoming black. In the stalactites from the vaults and 

 collars of old castles,'"* he says, " we could not detect the smallest 

 traces of humic acid." There could scarcely be found a more clear 

 and convincing proof of the absence of the humic acid of chemists, 

 in common vegetable mould." Under the term humic acid, Pro- 

 fessor Liebig undoubtedly means to include all those organic acids 

 arising from the decomposition of vegetable matter, and which have 

 received the names of crenic, apocrenic, geic, and humic acids. 



Having been informed by Dr A. A. Hayes of Boston, that he had, 

 in numerous examinations, arrived at results directly opposed to those 

 of Professor Liebig, I was induced, at his suggestion, to make an 

 examination of a large number of stalactites and stalagmites, obtained 

 from various localities, with reference solely to the presence or ab- 

 sence of organic matter in these bodies. 



The specimens examined were all from caverns or rock formations, 

 and were obtained from various parts of the United States, from 

 Trieste in Austria, Malta, and the Sandwich Islands. In coloui-, 

 they varied from an almost pure white, to red, yellow, and brown, 

 of different shades ; and in crystalline character, from a structure 

 resembling Arragonite, to a variety entirely wanting in symmetrical 

 arrangement, or a mere incrustation. The specimens were dissolved 

 in diluted hydrochloric acid, the flocculent matter separated, collected 

 and washed, boiled in caustic potassa, carbonate of ammonia, or car- 

 bonate of soda, and then tested in the usual way for crenic and apo- 

 crenic acids, by acetate of copper and carbonate of ammonia. In all the 

 varieties, with one exception, abundant flocculent organic matter was 

 separated, which, on testing, gave evidence of crenic acid in consider- 

 able quantities, with doubtful traces of apocrenic acid. The excep- 



VOL. Lll. NO. OIV. — AVRIL 1852. S 



