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experiments I found that clay possessed the same property, though in a limited 

 degree, and I recommended that, if it could be obtained at a cheap rate, it would 

 form a valuable auxiliary to the use of lime, and by increasing the retentive and 

 absorbent properties of the soil, would render them much more productive. 



I will now mention one or two other little subjects of investigation. I was 

 furnished by Mr. Johnson and Mr. Scobie with one or two specimens of a 

 substance found imbedded in a rock of Old Red Sandstone, at the Elms Quarry, 

 near Hereford. I produce a specimen of it — it puzzled those gentlemen to know 

 what it was. I found, on analysis, that it contained no organic matter, and, 

 when heated gently to a faint red, underwent no change ; submitted to an intense 

 heat before the blow-pipe, it merely became whiter in colour, and partially lost 

 its lustrous appearance. I did not estimate it quantitatively (not having time), 

 but I found it to contain peroxide of iron, alumina, lime, magnesia, and silica, 

 with a trace of potash. From its analysis, as well as its external appearance, I 

 decided that it was talc. 



On referring to some chemical works which I possess I found a very accurate 

 description of this substance given. It states there are two kinds ; however, I 

 will only mention the one nearly resembling the specimen. "In colour, white, 

 greenish, or grayish ; soft and soapy to the touch ; much more tender and brittle 

 than mica ; does not effervesce with acids, and is soluble therein with difficulty, 

 and consists of alumina, magnesia, silica, and sometimes lime and potash. It is 

 sometimes used as crayon, as an ingredient in rouge, importing a softness to the 

 skin, and is frequently used to give a fleshy tint to alabaster images." 



I have been furnished with a specimen of coaly looking matter by Mr. 

 Scobie, which I have examined. It contained, as near as possible, 50 per cent, 

 of carbon, the residue is iron and sand, and from the external portion, having the 

 combined iron simply as an oxide (Fe O) and the internal portion as peroxide 

 (Fe2 O3) I was led to believe that it was formed by the aggregation of car- 

 bonaceous particles, or decayed vegetation round a nucleus of peroxide of iron, 

 and that the carbonaceous matter, in a state of decomposition, reduced the peroxide 

 to a state of suboxide by the abstraction of oxygen for the formation of carbonic 

 acid, and this would account for the difference of colours between the external 

 and internal portions of the specimen. These are but little matters, but I have 

 thought fit to bring them before you in the hopes that the accumulation of little 

 facts would tend to the elucidation of others of greater importance. 



