Afi old Canoe from the I rive! I Valley. 247 



show that it was formerly a great lake, probably with forest 

 trees on the margin, and that it was fed by the Irwell and 

 subjected to occasional inundations of tidal water from the 

 Mersey, and that the outlet of this inland lake in course 

 of time became impeded by wind-blown sand driven from 

 the Mersey estuary by the western gales. 



This wind-blown sand not only impeded the drainage of 

 this inland lake, but, from time to time, changed the course 

 of the Irwell as well as that of the Mersey. The enormous 

 amount of clean sand, absolutely free from pebbles or 

 boulders, laid bare by the excavations of the Manchester 

 Ship Canal in the vicinity and immediately below Chat 

 Moss, is, I think, convincing" testimony of this. This sand 

 would effectually impound the drainage of the small rivulets 

 and water-courses from the upper lands of Patricroft, 

 Worsley, and Astley, the water from which before went 

 into the river through the lake, which would probably 

 extend right across to the Carrington side of the river to 

 the high lands of Lymm, and would be in shape similar to 

 the great Mersey Bay lower down the stream, into which 

 the Ship Canal enters, and which I will call Eastham Bay. 



The accumulation of rank vegetation would increase the 

 impediment, and in course of years the whole district would 

 become a moss, instead of a great lake. That the river bed 

 was formerly much deeper we have evidence in the discovery 

 of the old boat I have described, and in the great quantity of 

 old forest trees found even at much lower depths in the 

 Ship Canal cuttings. I have not been able to get the 

 exact levels all over the Moss, as it is difficult to obtain the 

 information. I, however, find that in some places it is 

 150 feet to the sand, and the depth varies to 50, ^o, and 

 25 feet. The greatest depth at present known is at a point 

 not far from Astley station, on the London and North 

 Western Railway ; indeed at one point in that locality it 

 is 180 feet deep. This places the level at the bottom 



