Palaeolithic Gravels of Somme Valley 149 



Professor Huxley said that investigation by M. Ducaze 

 Duthiers of the fluid from the Murex, 1 which produced the 

 Tyrian dye, was at first colourless, but when exposed to the 

 sun's rays, it became, first, bright yellow, then blue, and 

 finally red. The same investigator had taken a photo- 

 graphic negative from one of Ostade's pictures, and a 

 positive from this (which he exhibited) showed the red 

 colour. 



April 23rd, I2oth meeting (anniversary). Mr. Busk 

 described his visit to Amiens and Abbeville to study 

 the gravels. The more they were examined, the more 

 perplexing became the evidence as to their age, but he had 

 no doubt that the flint implements were the work of man, 

 were of great antiquity, and were much older than the 

 deposits in the bed of the Somme valley. He described the 

 stone coffins of Charlemagne's age, which were found in the 

 beds over the gravels. In these were human bones with 

 teeth in good preservation. 



Sir H. James exhibited some specimens of photozinco- 

 graphy, and gave a description of the process. 



On May 24th, Sir R. Murchison resumed the discussion on 

 the implementiferous gravels, calling attention to the fact 

 that the worked flints occurred in the lower part of these, 

 and were unworn, while the pebbles were rolled, and suggest- 

 ing that the latter might be long anterior to the former, and 

 have been transported to the place where the manufacture 

 had been carried on, and the two mixed up. As an illustra- 

 tion of this Professor W. H. Miller said that, in the Venetian 

 Alps near Cortina, he had seen beds of gravel not less than 

 forty feet in thickness, beneath which, as he was informed, 

 a village had been found. There had been time enough for 

 its inhabitants to escape, but not to remove their goods, 

 so that the works of man would occur under the gravel, but 

 no human bones. Some members of the Club doubted 



1 This, according to Canon Tristram (Land of Israel, 1865, page 51), 

 was M. brandaris, at any rate at Tyre, though according to some authorities 

 M. trunculus was the more usual source, but he says the masses of broken 

 shells, which must have been used to obtain the dye, consist almost entirely 

 of the first species. 



