96 RECENT EXCURSIONS OF THE 



As to the remaining pollards, the great question is, Shall they be 

 re-pollarded ? The reasons in favour of so doing are their drawn-up 

 character, owing to their having been left in an over-crowded state, 

 and the possibility of making them spread, and, a secondary reason, 

 pointed out by Sir Fowell Buxton, the variety of landscape colouring 

 obtained by the admixture of some of the dead leaves that hang on a 

 pollard with the young spring growth. The main argument against 

 the suggestion seems to be the danger of unauthorised lopping, 

 supplementing that undertaken by the Forest officials ; but the 

 extensive felling of the last few years does not seem to have 

 produced such a result, and it might be possible to have, at least, 

 provisionally, some temporary enclosures for such an experiment in 

 management, similar to those already made for the purpose of 

 planting. 



RECENT EXCURSIONS OF THE GEOLOGISTS' 

 ASSOCIATION IN ESSEX. 



UPMINSTER AND HORNCHURCH. 



ON March 5th there was an excursion for the purpose of visiting the cuttings 

 on the railway now being constructed between Upminster and Romford, a 

 northerly prolongation of that from Grays to Upminster. The first sections 

 inspected were those in the cutting west of Upminster Station, and east of the 

 Ingrebourne. They were seen to consist of London Clay, capped by a variable 

 thickness of gravel or loam, the former predominating. Here and there the 

 London Clay formed the surface for a few feet between two festoon-like beds of 

 gravel, a feature of frequent occurrence where the Clay is covered by these old 

 river deposits. The gravel of the high ground traversed by the railway between Up- 

 minster and Komford is of greater elevation and older date than that between Up- 

 minster and the Mardyke,the latter being only from 60 to 70 feet above Ordnance 

 Datum, while between Upminster and Romford the plateau is from about 90 feet to 

 a little over 100 feet. But, alike in each case, the surface gravel or loam is an old 

 river deposit, formed when the Thames flowed with a more northerly course and 

 at a higher level than it now does. Crossing the Ingrebourne the party entered 

 another cutting N.E. of the church at Hornchurch. There, in addition to 

 London Clay and old river-gravel, a hollow in the London Clay was seen to be 

 filled with Chalky Boulder Clay for a horizontal distance of about 300 yards, the 

 greatest thickness attained by the Boulder Clay beii)g about 15 feet. It was to 

 view this Boulder Clay, which lies about three miles south of any hitherto known 

 in this district, that the excursion was planned so unusually early in the year ; 

 and the party was fortunate enough to see a clear section of it close to its north- 

 westerly termination, the rest of the cutting having been sloped. Walking 

 thence towards Romford, cuttings on each side of the road at Butts Green were 

 inspected, that to the east showing only sand and gravel, while that between the 



