512 



REPORT OF NATIONAL MUSEUM, 1891. 



(Fig-. 38), a navigable canal lor the drainage and reclamation of the 

 Anchohne Level, there are indications that at some early day the river 

 was of mnch greater extent and importance, forming tlie drainage of a 

 broad lagoon or swamp, which upon a drift bottom gradually accumu- 

 lated alluvial deposit, interspersed Avith remains of fresh-water vegeta- 

 tion, the age of which may be roughly estimated from the existence of 

 two well defined forest beds in the Ancholme Level, one just below the 

 surface, and the other formed in the alluvial clay that collected upon 

 and between the bowlders left at the close of the glacial period, both 

 consisting of ])eat with large quantities of well preserved remains of 

 oak, yew, hazel, etc. 



The ancient lagoon was bordered on the east and Avcst by two well- 

 defined ranges of hills, which contracted in the vicinity of the present 

 Brigg, and there atibrded the i^eople of remote anti(j[uity the only 





Fig. 38. 



].,OCATin,\ OF r.OAT AND PLANK WAY. 



means of crossing this otherwise impenetrable morass. The first 

 record of any attempt to drain this marsh dates back to the reign of 

 Edward L It was reported to Edward 11 that "Man and Cattel ])ass- 

 ing over Glauuford Bridge in the time of fiouds were seldom out of 

 danger," and until the middle of the present century when the drainage 

 of the district was improved, the level was under water for several 

 months each year. 



It was at this place then, that, in 18S4, a most interesting discovery 

 was made, consisting of a I'Uoilc Hoad situated feet below the i)resent 

 level, and consisting of oaken planks riven from the tree, about lo ftH't 

 in length, and varying in width from 9 to 1(5 inches, fastened side by 

 side and placed with the straight side up, upon small trees and l)ranches 

 laid at right angles to the planks. The latter were secured by means 

 of stakes or round pieces of wood .'> or 4 inches in <liameter, driven 

 through rudely mortised stpiare holes into a bed of stone rubble under- 



