Natural History. 101 



its supervision into mile squares, each member taking one or 

 more of these squares and reporting all the large boulders 

 occurring in the area allotted to him. By this means a 

 systematic record is being made, and though we can hardly 

 expect our few, too few, fellow-workers in Lincolnshire to 

 adopt the same course just yet, it is to be hoped this method 

 will be carried out in time to come. 



Unlike the other sections of the Lincolnshire Naturalists' 

 Union, the Geologists are able to pursue their field-work, and 

 with good result too, during the winter months. In fact, for 

 boulder recording, wet weather is decidedly preferable, as the 

 rocks show off to far greater advantage when wet, and can thus 

 be identified with much greater ease. We need only go into 

 one of the numerous c cobble '-paved yards that abound in 

 districts where Boulder Clay occurs (the 'cobbles' being 

 generally obtained from the clay) to see this. In dry weather 

 they all appear to be of similar composition, but as soon as they 

 have been thoroughly cleaned with rain, it is quite surprising 

 what a variety of granites, porphyrites, schists, limestones, 

 sandstones, etc., can be seen. This variety is also noticeable, 

 though not to such an appreciable extent, among the larger 

 erratics. 



Mr. J. Lomas, speaking of striated surfaces in the Liver- 

 pool district, says c It is worth remarking that the striae more 

 thickly congregate in places where geologists reside?* Let us hope 

 that our Lincolnshire boulder reports will shortly show a 

 similar result. 



AN ARCHAEOLOGICAL HISTORY OF 

 THE WASH. 



By GEO. SILLS, 



of St. John's College, Cambridge, M.A,, and of Lincoln's Inn, Barrister-at-Lavu. 



THERE are few subjects of greater interest than the 

 change which in the course of ages has taken place in 

 our lakes and rivers. To take one or two instances : 

 The Thames was formerly an estuary, the remains of which 



* Glacialists 1 Magazine, vol. iii., 1895, p. 21. 



