309 



NOTE ON THE SOIL BELOW THE PEAT ON 

 MOUGHTON FELL. 



A. GILLIGAN, D.Sc, F.G.S. 



The source of origin of the siliceous soil which occurs below 

 this peat is discussed in the report of the excursion of the 

 Yorkshire Naturalists' Union to the Settle district, and is 

 attributed to ice-borne material washed in by melt-water. 

 I propose here to give the results of the mineralogical analysis. 

 Immediately beneath the peat the soil is grey in colour, 

 full of rootlets and about two inches in thickness. Next 

 comes a layer of ' iron pan 'about a quarter of an inch in thick- 

 ness, and below this is a very ferruginous sandy bed which 

 has been proved to a depth of four feet and is possibly much 

 greater in the hollows. Some of this sandy bed was taken 

 and after being broken up between the fingers, was dried for 

 twelve hours at 105° C. Of this, 200 grams were taken and 

 thoroughly sieved with the following results : — - 



> yVin-=i*6oo grms. ; < Jyin. >^\y in. =2-850 grms. 

 < TiVin- > bV in. =5-850 gms. ; < ^V in. > ^ in. =12-255 grms. 

 < T,V in. =177-490 grms. (by difference). 



All the separations were highly ferruginous and had to be 

 treated with hot dilute hydrochloric acid to remove the iron 

 oxide. The addition of the acid produced not the slightest 

 trace of effervescence, proving the absence of carbonates. 

 The cleaned separations of the coarser material were examined 

 in bulk with a binocular mineralogical microscope, when the 

 rock fragments and minerals in the various grades were found 

 to be as follows : — 



>yVin- — felspathic sandstone and grit, ironstone, chert, 

 with some fragments of slaty appearance. 



< yV in- >ir?T in. — felspathic sandstone, quartz, chert, with 

 a few fragments of ironstone. 



< ^}jj in. > Jjj in. — quartz (greatly preponderating) felspar, 

 mica. Very few chert and ironstone fragments. 



Some of the cleaned material < JL in. was mounted in 

 Canada balsam and examined in the usual way with ordinary 

 and polarised light. 



That which was < J^ in. > y^^ in. was almost entirely 

 quartz with a little felspar, mica and a few grains of chert. 

 Heavy minerals (given later) were also present in fair quantity. 



The quartz was subangular, having numerous inclusions 

 of regular, irregular and acicular types. The regular inclusions 

 noted include tourmaline, zircon and rutile. 



The irregular inclusions appear frequently arranged in 

 rows and some of them contain liquid with moveable bubbles. 



Inclusions of the acicular type, probably rittile, were not 



1918 Oct. 1. 



