390 PHILOSOPHICAL TRANSACTIONS. [anNO 1753, 



received last year, were fresher than those before sent. This year you will receive 

 the cods of silk, which makes the silk called kien tcheou, with the butterflies, 

 which come from them. The other things sent want no explanation. 



The empire of China abounds in mines of all sorts, as gokl, silver, copper, 

 tin, lead, iron, &c. The provinces which ])roduce the greatest quantity are, 

 Yun nan, and See tchouen. The two greatest rivers of China, Kiang and 

 Hoang ho, send down quantities of gold sand. The former takes its source in 

 the province of See tchouen, and the latter from Coconor; but they find mines 

 of gold and silver in the provinces of Yun nan. See tchouen, Chen si, Chan 

 tong, Hou kouang, Fou kien, Kouei tcheou, Pe tche si: but, for political rea- 

 sons, they work but few of them. He believes the principal is, lest the greedi- 

 ness of gain should excite popular insurrections. They open them sometimes in 

 one place, sometimes in another; but on the least appearance of a rising, they 

 immediately shut them up again. We cannot give any account of what is de- 

 sired, concerning the manner of working the several mines. We are not in a 

 way of informing ourselves. As to what regards petrifactions, he had only seen 

 a few crabs, pieces of wood, and some bones, which he takes to be those of 

 buffaloes. 



The Chinese have but a very confused idea of a universal deluge. They only 

 conclude from things seen on the surface of the earth, that there must formerly 

 have been some terrible hurricane, ari3 that the sea had covered the face of the 

 earth. A great mandarin, who had a better understanding than the Chinese 

 commonly have, being sent into Ho nan, to visit several places, observed, on 

 the top of a very high mountain, a kind of basin, the circumference of which, 

 formed by the mountain, was filled with different figures of fishes, shells, and 

 marine plants, impressed on stones; he said to another mandarin, who accom- 

 panied him, " Certainly the sea must have been here; these fishes, shells, and 

 plants are found only in the sea." F. Gaubil says, the Chinese books pretend 

 that such impressions are found on the highest mountains of Thibet, and See 

 tchouen. 



The greatest part of the cinnabar of China comes from the province of Yun 

 nan : and it is said there is some also in Kiang si, Hou kouang, and Koui tcheou. 

 Kang hi, the great grandfather of the present emperor, ordered a general search 

 to be made through the whole empire for antimony, but found none in any of 

 the mines. 



XXXV III. On the Cause of the Different Refrangibility of the Rays of Light. 



By Mr. T. Melville, p. 261. 



In order to account for the different refrangibility of the differently-coloured 

 rays. Sir Isaac Newton (Optics, Query 29), and several of his followers, have 



