64 



Economical Geology. 



miles. An attempt was made, some years ago, to explore one of 

 these beds, under the impression that the ore was iron. But how 

 extensive either of them is, it is difficult to determine, as each seems 

 to consist of a number of small beds — or rather the ore is interlam- 

 inated with the slate. The occurrence of so much silicious oxide 

 at these localities, is very interesting to the mineralogist, because this 

 ore is so rare in Europe. 



In Conway. 



A distinct vein of the black oxide of manganese several feet wide 

 occurs in the southeast part of this town, the gangue being quartz. 

 It has not been explored at all ; nor is the manganese ore very 

 abundant at the surface. I do not doubt however, that this ore may 

 be found here in large quantities. 



In Hinsdale, N. H. 



An extensive bed or vein of the black oxide, and ferra silicate of 

 manganese have been found in this town. It appears near the top of 

 a hill and the adjacent rocks are not visible. 



In Winchester N. H. 



Between one and two miles east of the center village in this town, 

 may be seen in large quantities of the black oxide and ferra silicate of 

 this metal of the same character as in Hinsdale. These localities 

 have, as yet, attracted no attention except from a few mineralogists. 

 My information and specimens were furnished me by Mr. John L. 

 Alexander of Winchester. 



Tin. 



I am able to say with perfect confidence that this interesting metal 

 exists in Massachusetts ; but can add little more. I found only a sin- 

 gle crystal of its oxide, weighing 50 grains. But this I dug myself 

 from a block of granite in the north east part of Goshen, and on re- 

 ducing it to metallic tin, it corresponds exactly in every respect with 

 that metal from England. I have never been able to find any more 

 specimens, but it ought to be borne in mind that in England, accord- 

 ing to a geological writer of that country, " it is generally in the vi- 

 cinity of a vein of tin ore, that disseminated grains of tinstone are 

 found in the rock." 



