On the Geological Value of Recent Occurrences. 371 



brackish water deposits in Permian, Carboniferous, and Triassic 

 times, whose commingle of marine, fresh water, and terrestrial 

 organisms have puzzled the geologist. This is the occurrence 

 in question. 



" The Floods in Califoknia. — San Francisco, February llt7i. — I 

 have just received your letter, which has been double its usual time 

 getting here, owing to our fearful visitation of tempest and flood. 

 We have been shut out from the world ever since the 15th of Decem- 

 ber last. It began to rain on the 1st of December, and we did not 

 regard it much, for we looked for the annual rains. But the rain — 

 which, as usual, was snow in the mountains — continued the whole of 

 the month of December, and about the middle the mountain snows 

 began to melt, as the rain had actually got warmer. The consequence 

 was that the Sierra ISTevadas poured down rivers upon rivers of 

 water, until the whole of that great basin of California which the 

 mountains bound was entirely submerged. The only outlet to this 

 water is the Gulden-gate, the entrance to the bay at San Francisco 

 from the Pacific Ocean. Take the map of California, and see where, 

 on the south, the mountains come to a point below Tularo Lake, and 

 then go up north to where they again join at Shasta, and then pic- 

 ture the whole of the immense tract of land they enclose under 

 water, and the bay of San Francisco a vast river, pouring its volumes 

 into the Pacific Ocean by the before-named Golden-gate. Fancy, 

 also, the tides of that ocean having no effect in our bay, and welling 

 up at its entrance, and you will have a feeble idea of the magnitude 

 of the volume of water that has for two months ravaged California. 

 Not a ship could enter our harbour, and only the most powerful 

 steamers could stem the torrent. Sacramento, Marysville, and 

 Stockton, our three principal interior cities, all under water, and all 

 communication cut off with them excepting by boats. Business com- 

 pletely at a stand-still, no goods going up and no money coming 

 down. It was very strange to see the sea for about ten miles around 

 the mouth of our bay. In the interior, about sixty miles from San 

 Francisco, and at the embouchure of the northern rivers, are vast 

 tracts of land covered with rushes and semi-aquatic plants, that go 

 by the name of tule lands, something like the paddy-fields of India. 

 Well, as the waters rose, these immense morasses rose also, and in 

 process of time, becoming detached, floated away with the current in 

 masses of from 100 yards to half a mile in size, and they all floated 

 out to sea, travelling, some of them, more than 100 miles before their 

 arriving. Once arrived in their grander sphere of action, it was the 

 most extraordinary thing to see the myriads of water-snakes, faithful 

 to their home, twisting and twirling in the salt sea, and to see the 

 water-fowl that screamed over their nests as though warning the 

 islands of their danger, and to see our coast when any of the islands 

 were thrown up on it, and the thousands and thousands of snakes 

 wriggling their way over the shrubless sands that bound it for miles 

 in search of anything to hide them from the wholesale slaughter that 

 sticks and stones, and knives and even guns made among their host. 

 We wanted St. Patrick to come. You know the innate dread we 



