2(IG Discovery ofChromale of Iron in Shetland. 



but these are only from two to three inches in breadth, some- 

 times increasing to the breadth of five or six inches. Many 

 masses are elsewhere observable, extending a few feet and then 

 losing; themselves in a general dissemination throughout the ser- 

 pentine rock in wliich they occur. This dTssemination consists 

 in the difl'usion of granular particles of the colour and size of 

 gunpowder. 



It is evident from this description that the most promising ap- 

 pearance of the ore is adjoining the house of Mr. Edmonstone ; 

 and from this gentleman, whom I have made ai quainted with all 

 the circumstancesof the mineral, any commercial inquiry will meet 

 with the most satisfactory answer. Letters may be directed, 

 *' Thomas Edmonstone, esq., of Buness, Island of Unst, Shetland." 



Upon the encouragement, however, from London will depend 

 the renewed searches after the chromate of iron, not only on 

 Mr. Edmonstone's grounds, but in the adjoining hills, which are 

 the joint property of several landed proprietors in Unst. From 

 the quantity, therefore, of the ore which has been found in de- 

 tached portions on the hills, and from the promisina; appearance 

 on Mr. Edmonstone's grounds, I would submit to the manufac- 

 turing chemists in London the propriety of rendering to the 

 Shetland gentlemen every scientific assistance which they may 

 require from their advice, or even, if wanted, from other exer- 

 tions in prosecuting the search after this ore, provided its quality 

 suits their purpose. It appears to me that some serious obsta- 

 cles caimot fail to result from the inexperience of the Shetland 

 gentlemen in whatever concerns the operations of mining. 



Vessels trading from Leith to Shetland visit Balta Sound al- 

 most every montli in the course of the spring and summer. 



In furnishing the foregoing particulars relating to the chro- 

 mate of iron, I have only to add that I shall be happy to answer 

 any personal inquiries on the subject, concerning whatever I may 

 have left unexplained. Samuel Hibbeut, M.D. 



Portions of the specimens of chromate of iron transmitted by 

 Dr. Hibbert were put into the hands of several members of the 

 Society for examination, with respect both to the quality and 

 richness of the ore as compared with that imported from the 

 United States. Samples of chromate of lead j)repared from the 

 American and Shetland varieties of chromate of iron were laid 

 before the Committee by Mr. Midgley, one of the chairmen of 

 the committee of chemistry, who has had large experience in thii 

 branch of chemical manufacture. The result of this gentleman's 

 investigation (confirmed by the experiments made by other mem- 

 bers of the Society) is, that the ore from Shetland in quality is ff 

 quite equal to that imported from America, and in richness, as I 

 far as can be judged from a few specimens, is superior. 



XLIII. Ob- 



