December 15th, 1896.] Proceedings. 



xix. 



water from some springs near Uzes to the town of Nimes. 

 The bridge itself is said to be 880 feet long, and 160 feet 

 high from the bed of the river, and it consists of three tiers 

 of arches of immense stones, the lowest tier having six, 

 the next ir, and the topmost 35 arches. The river being 

 apparently rather low at the time, he was able to step on 

 to a platform of rock in the bed on which one of the piers 

 of the lowest series of arches rested. It did not appear 

 to present any indication of having been eroded below the 

 level of the portion beneath the pier itself, nor did the 

 bridge, which he was able to cross, from one side of the 

 valley to the other, along the old channel or conduit at 

 the top, present any appearance of having sunk since the 

 foundations were laid. On the whole he should say that 

 neither the bridge nor its foundations in any way suggested 

 that the bed of the river had been lowered since the 

 structure was erected. He admitted that his examination 

 in this respect had been rather cursory, as at the time of 

 his visit, on a winter afternoon, dusk was rapidly coming 

 on. But he mentioned the matter because he had not 

 observed that bridges had ever been referred to as affording 

 evidence of the erosion or the rate of erosion of river valleys. 

 He supposed there were not many cases in which a bridge 

 2,000 years old could be examined as a witness, and he, 

 therefore, thought it worth while to inquire whether any 

 attention had been given to the Pont du Gard with the 

 object indicated. 



Mr. J. Cosmo Melvill, M.A., read a paper entitled 

 " Descriptions of New Species of Marine Mollusca 

 from the Indian Ocean and Persian Gulf, dredged 

 by Mr. F. W. Townsend." 



The paper is printed in full in the Memoirs. 



Professor S. J. Hickson, F.R.S., read a paper entitled 

 "On the Ampullae in some Specimens of Millepora 

 in the Manchester Museum." 



The paper is printed in full in the Memoirs. 



