138 Dr Hibbert on some Remarkable Concretions 



actually the arrangement. The external surface consisted of 

 the red oxide, quite pure ; below this was the ordinary mag- 

 netic oxide (pxidumferrosoferricum of Berzelius,) and farther 

 in the quantity of protoxide gradually increased to the com- 

 mencement of the interior layer, which he found homogeneous 

 throughout. It appears, then, to be determined by these ex- 

 periments, that we have two combinations of the peroxide of 

 iron with the protoxide, that is, the magnetic oxide Fe + Fe, 

 and the less magnetic one which forms the inner layer of the 

 oxidated crusts produced upon metallic iron by heat, Fe+3Fe. 

 Stockholm, November "\0th 1825. 



Art. XXVI. — On some Remarkable Concretions which are 

 found in the Sandstone qf Kcr ridge in Cheshire.* By Sa- 

 muel Hibbert, M. D. F. R. S. E. and M. G. S. Secretary 

 to the Society of Scottish Antiquaries. Communicated by 

 the Author. 



The stony concretions that form the subject of this short pa- 

 per are found under circumstances that it will be previously 

 requisite to describe. They are obtained from a sandstone of 

 the coal formation composing a small ridge of hills named 

 Kerridge, situated about three miles from Macclesfield, in 

 Cheshire. Not far distant is the more recent deposit of the 

 newer red sandstone, or red marie formation. Near the junc- 

 tion of the sandstone, of the coal formation, and of that of the 

 red marie, there is a considerable disturbance of the strata. 

 The celebrated hill of Cheshire, Alderly Edge, which rises 

 abruptly from a level country, has its strata of the newer red 

 sandstone, inclined at about an angle of 20*, while the adjoin- 

 ing strata of the same formation are nearly horizontal ; and 

 in like manner, the strata of Kerridge belonging to the sand- 

 stone of the coal deposit, exhibit numerous faults and disloca- 

 tions, being likewise intersected by small rents, or fissures, 

 such as I have observed to take place in the vicinity of whin 

 dikes; but, in this instance, the disturbing cause has not 

 made its appearance. The seams of coal in the imme diate vi- 



* Read at the Royal Society of Edinburgh, 5th December 1825. 



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