92 On Columbitc and other North American Minerals, 



not having a sufficient quantity of the mineral to make a com- 

 plete analysis ; but its external characters, crystalline form, and 

 the few chemical experiments I have made, together with the 

 great probability of the substance I examined being the same 

 alluded to by Berzelius, leave little doubt that it is Columbite. 

 Still I hope, by examining a considerable number of speci- 

 mens, to find a sufficient quantity of the ore to undertake a de- 

 tailed analysis. 



If I am correct in my determination of the Haddam mineral, 

 we have a clue, perhaps, to the discovery of the long-lost Co- 

 lumbite. The original specimen is said to have been found in 

 New-London, which place is not more than 25 miles from 

 Haddam. It is true, that the largest piece of ore yet seen from 

 the latter locality, does not much exceed half an inch in dia- 

 meter, while that in the British Museum is said to weigh seve- 

 ral ounces ; but it is reasonable to expect, that, when the new 

 locality is thoroughly explored, masses of considerable size 

 will be discovered. There is another circumstance which fa- 

 vours the opinion that the mineral analyzed by Mr. Hatchett is 

 of the same variet}', and from the same locality, as that of 

 Haddam, which is, the specific gravity of the latter. The 

 North American Columbite was found by Dr. Wollaston to 

 be much lighter than that of Sweden, the cause of which was 

 supposed to be small cavities in the former, and in confirma- 

 tion of this opinion, I would mention that the Haddam Colum- 

 bite, when immersed in water, continued to give out minute 

 bubbles of air for a considerable time, after which the specific 

 gravity was much increased. 



Phosphate of Manganese. There is but a single North 

 American locality of this rare mineral given by Cleave- 

 land, who remarks, that " it is said to occur in Pennsylvania." 

 I have not been able to ascertain either in what part of that 

 state it is to be found, or upon whose authority the locality is 

 ^iven. About a year since, Mr. Nuttall placed in my hands 



