224 On the Recent Discovery of Flint Implements 



joins a small stream called the Bourne, and forms a kind of 

 buttress which separates the two valleys. It is however separated 

 from the main tract of high land by a transverse depression 

 about 30 feet in depth, so that it forms an isolated hill en- 

 tirely disconnected by valleys of greater or lesser depth, from 

 any high ground. From this peculiar conformation it will 

 be evident that when the gravel was deposited on Milford 

 Hill, the ancient river would during the variations of its course 

 have extended from Laverstock Hill on the east, to Harnham 

 Hill on the west, a distance of about two miles. The drift at 

 Milford completely invests the summit of the hill, is thickest at the 

 top, where it attains a depth of from 10 to 12 feet, thins out gradually 

 on the sides, and ceases altogether rather more than half-way 

 down. It is quite free from anything like stratification, rests 

 unconformably on the chalk, running down in many places into 

 shallow pot holes. As measured by the aneroid, it is about 100 

 feet above the present level of the river Avon. In many 

 places there is at the base of the compact gravel, resting upon 

 the chalk, an irregular deposit of pale fawn-coloured chalk- 

 rubble, which contains a small admixture of flint gravel, but 

 no organic remains. Some few years since, a good section of 

 this drift was exposed on the south-eastern side of the hill in a 

 cutting made for the London and South Western Railway ; and 

 here near the base of the gravel, a narrow seam of loose light 

 coloured sand containing shells was discovered. The shells in this 

 one spot existed in the greatest abundance, and although ex- 

 tremely friable were generally unbroken. They consisted prin- 

 cipally of Helix hispida in all stages of its growth, a few 

 specimens of Helix arbustorum and a single individual of Zua 

 subcylindrica. All these shells are terrestial, and in every way 

 agree with examples of the same species still living in the 

 adjacent fields. With the single exception of a fragment of 

 an upper molar tooth of a species of Equus, no bones or mammalian 

 remains have as yet been discovered, either at Milford Hill or 

 any high level gravel in this neighbourhood. At no other point 

 in the gravel has any seam of sand containing shells been 



