Suhimrmi ForeJ} on the rnjl Co^Ji of England. 217 



it was firm, efpeclally in the roots. The people of the country have often found among 

 them very found pieces of timber, fit to be employed for feveral economical purpofes. 



The forts of wood which are ftili diftinguifliable, are birch, fir, and oak. Other woods 

 evidently exift in thefe iflets, of fome of .which we found the leaves in the foil ; but our 

 prefent knowledge of the comparative anatomy of timbers is not fo far advanced as to afFord 

 us the means of pronouncing with confidence refpeJling their fpecies. In general, the 

 trunks, branches, and roots, of the decayed trees, were confiderably flattened ; which is a 

 phenomenon obferved in the furtarhrand-, or foffil wood of Iceland, and which Scheuchzer 

 remarked alfo in the foflil wood found in the neighbourhood of the lake of Thun, in Swit- 

 zerland. 



The foil to which the trees are affixed, and in which they grew, is a foft greafy clay ; but 

 for many inches above its furface, the foil is entirely compofed of rotten leaves, fcarcely 

 diftinguifhable to the eye ; many of which may be feparated, by putting the foil tn water, 

 and dexteroufly and patiently ufing a fpatula, or blunt knife. By this method I obtained 

 fome perfe(3: leaves of illex aqulfolium-, which are now in the herbarium of the right honour- 

 able fir Jofeph Banks, and fome other leaves, which, though lefs perfeft, feem to belong to 

 fome fpecies of willow. In this flratum of rotten leaves, we could alfo diftinguifh feveral 

 roots of arundo phragmites. 



Thefe iflets, according to the mofl accurate information, extend at leaft twelve miles in 

 length, and about a mile in breadth, oppofite to Sutton fhore. The water without them, 

 towards the fea, generally deepens fuddenly, fo as to form a fteep bank. The channels 

 between the feveral iflets, when the iflets are dry in the lowefl: ebbs of the year, are from four 

 to twelve feet deep ; their bottoms are clay, or fand, and their direction is generally from eaft 

 to Weft. 



A well, dug at Sutton by Jofhua Searby, fliows that a moor of the feme nature is found 

 under ground in that part of the country, at the depth of fixteen feet ; confequently, very 

 nearly on the fame level with that which conftitutes the iflets. The difpofition of the ftrata 

 was found to be as follows : 



Clay, - - - . _ ' - _ . 16 feet 



Moor, fimilar to that of the iflets, from - - - . 3 to 4 do. 



Soft moor, like the fcowerings of a ditch bottom, mixed with ihells and filt, ♦ 20 do. 



Marly clay, - - - _ . _ i do. 



Chalky rock, from - - . . . . « l to 2 do. 



Clay, -------_ 21 yards. 



Gravel and water. The water has a chalybeate tafte. 



In order to afcertain the courfe cf this fubterraneous fl:ratum of decayed vegetables, fir J. 

 Banks direiled a boring to be made in the fields belonging to the Royal Society in the parirti 

 of Mablethorpc. Moor, of a fimilar nature to that of Searby's well, and of the iJlets, was 

 found very nearly on the feme level, about four feet thick, and under it a foft clay. 



Th# 



