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THE POPULAR SCIENCE MONTHLY 



The sixth station is situated in California, 112 miles north of San 

 Francisco, one mile south of the city of Ukiah, the county seat of Men- 

 docino County. The observatory is located toward the western edge of 

 one of the numerous small valleys in the Coast Range of mountains. 

 The valley, which is traversed by the Eussian River, is about ten miles 

 long and from two to three miles wide, and surrounded by mountains 

 of an average height of about 1,300 feet above the floor of the valley. 

 The altitude of the observatory is 700 feet above sea-level. The meteor- 

 ological conditions at this station are very favorable, standing next to 

 those of Carloforte in this respect. Snow seldom falls and, although 



INTERNATIONAL LATITUDE OBSERVATORY , UlvIAH, CALIFORNIA. (Looking South. ) 



the summer temperatures are sometimes extreme, the nights are al- 

 ways cool, which adds much to the comfort of the observer if not to 

 the accuracy of the observations. Up to May, 1903, the observations 

 at this station were made by Dr. Frank Schlesinger, now director of 

 the Allegheny Observatory; from that time until September, 1907, the 

 observations were made by the writer of this article. The work is 

 now in charge of Dr. James D. Maddrill. 



From a seismological point of view, all the American stations are 

 favorably located. Although the Pacific Coast of the Americas is well 

 recognized as a region of seismic activity, yet the mountainous nature 

 of the country surrounding TJkiah seems to afford a measure of pro- 

 tection from these disturbances. No- earthquake since the observatory 

 was established, not even the great shock of April 18, 1906, has been of 

 sufficient intensity to interfere in any way with the progress of ob- 

 servations. 



