^ Proceedings of the 



has been rendered navigable as far as Guildford. In former days a canal 

 continued tbe navigation to tbe Arun, and thence to the sea. (6.) The 

 sixth and last river to which I shall refer is the Bourn Brook, which hag 

 its principal sources near Bagshot and on Bisley Commcm, near the Chob- 

 ham Eidge. This is almost entirely a river formed from drainage of the 

 country. Its entire course of about twelve miles is through the Bagshot 

 sand. It presents but few features of interest, is sluggish, and its waters 

 have a stain of peat, like other streamshaving their sources in that formation. 

 Havinf regard to the geological formation of the country, it may be 

 observed" that the chalk strata and the upper and lovrer greensand strata 

 have been thrust up and tilted by the upheaval of the Wealden series, so 

 that in the range of the North Downs the gradual slope of the chalk is 

 towards the north, and a like inclination exists in the strata of the greensands. 

 When we come to the west side of the county, where the chalk retires into 

 Hants, the lower greensand occupies a much more extensive area than in 

 the east of the county. In the extreme west the tilt of the greensand and 

 of the chalk beyond it is towards the west, the steep side of both formations 

 iacino- the east ; but whether the slope of the hills is north or west, in either 

 case we find that the sources of those rivers having their rise in the chalk 

 or in the greensand are from the land on the gradual slope of the hills, and 

 not from land at foot of the steep side of the bills. I do not say that no 

 streams issue from the steep side, but those which do are scanty in their 

 supply of water compared with those which rise from the northern or 

 western slopes. In the original condition of the chalk and greensand strata 

 I apprehend the subterranean channels were horizontal or nearly so. When 

 these series were thrust up and tUted by the upheaval of the Wealden 

 series, the subterranean channels for water were tilted also ; hence becoming 

 charged with water m their lower termination, they broke through the 

 ground in springs of more or less abundance. The chalk and gravels and 

 ■and would not afEord much surface drainage, but would absorb the rain- 

 fall, hence in the northern surface of the chalk comparatively few drainage 

 streams are found, but the waters burst forth as springs at various places 

 down the incline. And on the northern or western sides of the greensands 

 the waters find their outlet at foot of the northern or western slopes, not 

 under the steep side or escarpment of the series. I have not been able to 

 examine so fully the nature of the streams in the Bagshot sand, but perhaps 

 some member of the Club can give information on this point. So far as my 

 memory serves, they are sluggish and of dark colour, and hence the name 

 of Blackwater, which is one of the principal streams of that series, but 

 •which is a river of Hants and Berks, not of Surrey. In the hands of some 

 other member of the Club this subject might have been made more interest- 

 ing • reference might have been made to incidents in connection with the 

 rivers, to mansions on their banks, to parks through which the streams run, 

 and to many other subjects which would naturally occur to a poetic mind, 

 but which I regret have not come under my notice, or have not been 

 retained in my memory, for I am sorry to say my imagination is like the 



