J 813.] Scientific Intelligence. 149 



accompanied with your remark, noticing the transition lime-stone 

 of that district. 



The chalky lime-stone stratum of the Wolds, of which Flam- 

 bro' Head is the most easterly point, and Leavening Brow the 

 most westerly, is of very considerable depth, as the cliff from 

 Flamhro' to" Spector, and the wells that have been made for 

 obtaining water, indubitably prove. The cliff at Spector appears 

 to the eye at least 400 feet perpendicular, and is one entire bed 

 of the same stone, not intersected by any veins whatever, and 

 containing various shells wherever a quarry is opened in this 

 extensive stratum. 



Flambro' Head and Filey Bridge are the two most easterly 

 points of the bay generally called Filey Bay. From Flambro' 

 Head to Spector the white cliffs of Albion appear for the last 

 time in sailing to the North; and at Filey Bridge the dark colour 

 of the moor-stone district begins, which continues to the most 

 northerly point of Britain. 



Fdey Bridge has been formed by the Ocean gradually washing 

 off an immense bed (100 feet thick) of argillaceous earth from 

 the rocky base, which dips in a southerly direction ; and in the 

 highest part is not more than 50 or 60 feet above high water 

 mark. This base I call a firm argillaceous sand-stone ; it is in 

 large blocks, containing shells, and intersected by grey lime-stone 

 in thin strata, from G to 18 inches, containing also various shells, 

 particularly the large ostrea, and dipping at the same angle, and 

 in the same direction ; the angle about 15 degrees. 



Should these observations recal to your memory the minutes 

 you would of course make in your geological view of the East 

 Riding of Yorkshire, perhaps you will favour the county with a 

 publication of them, at some convenient opportunity, in the 

 Annals of Philosophy. This, I am sure, will oblige your York- 

 shire friends ; and particularly, Sir, 



Your most obedient servant, 

 July 7, 1813. I. W. M. 



To Dr. Thomson, M. D. &jc. Sfc. 



V. Structure of the Cube. 



The following letter deserves to be laid before the public, 

 because it forms what 1 consider as a valuable addition to Dr. 

 VVollaston's ingenious explanation of the structure of crystals 

 from spherical particles of matter. 



silt, 

 Dr. Wollaston, in the Bakerian Lecture published in the Phi- 

 phical Transactions, shows very ingeniously in what manner 

 the regular tetrahedron and octahedron may be formed of sphe- 

 rical particles. 



