274 TRANSACTIONS OF THE 



But on the Pacific side of our continent, the storm-controlling forces act 

 in a direction from west to east, especially upon the coasts of 



CALIFORNIA, 



Oregon, and Washington. The warm Kuro Siwo, or Japan stream of the 

 great- ocean, after reaching the middle latitudes, on the way to the Aleu- 

 tian Islands, is superficially brought under the propelling power of the 

 westerly or anti-trade winds, and a large drift of this Pacific Gulf Stream 

 is borne eastward as a decidedly marked warm stratum of surface water, 

 and strikes upon the western shores of America nearly at right angles. 

 This agency, as well as that of the general atmospheric movement on our 

 Pacific Coast, serves to give character and direction to the storms and 

 cyclones which reach it, no doubt, from the western Pacific Ocean. 



From San Diego to the Straits of Juan De Fuca, from December to April, 

 the storms of the 



PACIFIC COAST 



Set in, with southeasterly winds, veering as the storm center progresses, to 

 southwesterly. The closing winds from the north of west are very severe, 

 and, as they blow onto the lee shore, are to be apprehended by vessels, 

 even though in port. Instances are not wanting in which vessels have been 

 sunk in the Pacific ports of America by these gales from the west. These 

 southeasterly gales are more frequent and violent north of San Diego, and 

 thence along the coast to 



BRITISH COLUMBIA. 



This can be easily understood from the fact, as established by Blodget, 

 that the humidity and rainfall of the region stretching from San Francisco 

 northward to Vancouver Island are nearly three times as great as of that 

 south of San Francisco. Unless forced by other causes to deviate from the 

 regions of greatest humidity, we know storms seek or are drawn into such 

 regions for their necessary supply of aqueous vapor. On the Pacific Coast 

 there are no other known agencies which would cause such deviation. It 

 follows, therefore, that the ports of 



SAN FRANCISCO, 



And Portland, Oregon, and the waters of the adjacent sounds, are more 

 endangered by storms than San Diego or those .points along the coast 

 between San Diego and San Francisco. In Summer the latter port is so 

 far south of the usual storm track that it is comparatively safe ;. but it is 

 otherwise from December to April. The northeasterly wind, which on the 

 Atlantic seaboard is often a violent premonitor of a storm, on the California 

 coast and northward does not precede, but follows the cyclone in its closing 

 northwest quadrant, and is usually of moderate force. 



After striking the Pacific Coast the storm will generally advance with 

 but little diminution of cyclonic intensity, but with diminished progressive 

 motion, in a direction east-northeast. The violence of the storm will not 

 cease till the center has passed beyond the 



COAST RANC4E MOUNTAINS. 



The great upper current or stratum of warm and moist equatorial atmos- 

 phere, which in England has been observed to move in a southwest direction, 



