Notes on the Flora of Silhury Hill. 159 



expedients adopted by our ancestors under the idea of forwarding 

 the national interests. 



" Q,uid vides ? mutato nomine, de te 

 Fabiila narratiir." 



Certainly we of the nineteenth century, with all our presumed 

 light and knowledge, must yet wait a little while, ere we criticise 

 too minutely what we are ready enough to deem the bungling 

 legislation of the days of the Plantagenets.' 



^ote0 an tlje J^lora of cSilburg pill 



By J. BacKMAN, F.L.S., F.G.S., &c., Professor of Botany and Geology. 



I^^HE interesting artificial mound known aa Silbury Hill, has 

 I been. so fully examined by the antiquary, that little remains 

 to be done ; but as Natural History forms part of the studies of the 

 Wilts Society, I purpose making a few observations from this point 

 of view. 



The mound from its size is justly entitled to the name of Hill, 

 and yet there can be no doubt that its present aspect is due to 

 artificial means. In all probability the base is of the chalk rock in 

 situ, while the upper part was formed from the material removed 

 in levelling the plain from which it so boldly rises ; and so flat is 

 the surrounding soil that it forms an irrigated meadow, which is 

 remarkable for its pure grass herbage, which both in quantity, 

 quality and early maturity can scarcely be surpassed. The 

 stream from which the irrigating waters are supplied is constantly 

 dry in summer, owing to the porosity of the chalk strata ; a geolo- 

 gical condition which has given rise to the Wiltshire name of 

 Winterbourne, or winter brook, from the circumstance that it is 

 only in the wet season that the strata afibrd sufl5cient water to 

 require or form rivulets for the drainage of its soil. 



^ The Editors regret that owing to the serious illness of the author, they have 

 not had the advantage of his corrections in passing this paper through the press. 



