220 Dr. L. Moi/sei/ — On the Splitting of Nodules. 



Wareham district we have no direct information from ilr. lleid, yet 

 the following passage (p. 25 of Dorchester Memoir) may possibly 

 throw some liglit on the as yet unproved strata below the termination 

 of the AVorgret borehole : " Close to Organ Ford, and for nearly 

 a mile to the westward, white pipeclay mixed with carbonaceous clay 

 can be seen in the road soutli of the stream. This bed is apparently 

 equivalent to the stratum that is worked at its southern outcrop round 

 Creech, though at its northern outcrop it does not appear to be more 

 than 50 feet above the London Clay." The statement is important as 

 showing that in the neighbourhood of Organ Ford, rather more than 

 three miles due north of Wareham, the Pipeclay scries, towards its 

 northern outcrop, is quite low down in the Bagshot system. Now, 

 when we come to consider the bearing of these facts on the hypo- 

 thetical estimate of 85 feet for the " Kemainder of the Bagshot Beds 

 iinpi'oved," as given for series E in a tabular column attaclied to the 

 Report,' it seems to encourage the belief that, when tlie boring rod 

 reached 215 feet from the surface of the Worgret Hill plateau, 85 to 

 100 feet would be a fairly liberal estimate of the thickness of the 

 remainder of the Bagshots. The chief element of uncertainty lies in 

 the fact that the Pii^eclay series was not gone through, but we may 

 assume almost with certaintj^ that a third Bagshot Sand-series, with 

 a development of 60 or 70 feet, would still have to be encountered ere 

 the Lower Tertiaries were reached. 



{To he concluded in our next Number.) 



YI. — On a Method of Splitting Ironstone I^odules by means of 



AN AllTIFICIAL FbEEZING MiXTURE. 



By L. MoYSEY, B.A., M.B., B.C., F.G.S. 



I TOST geologists who have had anything to do with the ironstone 

 nodules in the Coal-measures have been struck by their perverse 

 and refractory behaviour under the hammer. How one nodule will 

 refuse to break under the most well-directed blows, and another, 

 though breaking easily, will exhibit to the disappointed collector 

 a clean bright surface of clay-ironstone, without a trace of that 

 organism that he hoped, and almost had a right to expect, was there. 

 It seems therefore necessary to find some other and perhaps less 

 violent method of breaking them. 



The nodules used for the following experiments were taken from 

 a now disused brickfield situated near Ilkeston, m Derbyshire, on the 

 Shipley Hall estate, owned by E. M. Mundy, Esq., the horizon being 

 just below the Top Hard Coal. The clays of this pit, unlike most of 

 the South Derbyshire Coal-measure clays, teem with nodules for the 



1 This refers to the Report made hy Mr. Iliullestou to the Towii Council of 

 Wareham as to the advisability of contiuuiug the boring. In this Report the 

 particulars of the work already executed are given in a tabular form together 

 with an approximate estimate of the probable thickness of the remaining Tertiaries 

 ere the Chalk was reached. The total thickness of the beds above the Chalk on 

 Worgret Hill was finallv estimated at 425 feet. 



