116 PROCEEDINGS OF THE CALIFORNIA 



former there will be but little rain, aud a cool, dry atmosphere ; in the latter a 

 warm and moist atmosphere, and generally a free rainfall, although it is where 

 the edges or sides of the currents touch that the greatest fall of rain will be 

 found to take place. There can be no doubt but that these currents are subject 

 to periodical and, apparently, also accidental displacements. Of the former we 

 at present know nothing, or at least but very little, and of the latter but few 

 observations have been made. Muhry and Dove, the German Meteorologists, 

 have recorded some instances of this displacement which accompanied European 

 storms ; but from the disturbing influences that on the old continent interfere 

 with the regular movements of the air currents, it is probable that this continent 

 will afford the best field for these investigations when the attention of observers 

 shall be more fully directed to these general movements instead of being too 

 exclusively devoted to the registering of the less important local changes in 

 temperature and pressure. If ever meteorology is to become a really useful 

 science to the agriculturist, it is in this direction, I think, its advantage will be 

 secured. There can be no doubt but that questions of the greatest importance 

 connected with agriculture, particularly in this State, are dependent on the 

 existence and position of these air currents ; and if ever any scientiflc foundation 

 for predicting the weather is obtained, I am convinced it will be by ascertaining 

 the laws that govern the movements of these vast air belts that carry with them 

 seasons of plenty or of famine. From even a very imperfect series of observations 

 made in connection with this subject since I have been in California, I am con- 

 vinced that its more thorough investigation will lead to a scientific basis of 

 weather predictions, as regards the general character of the seasons ; and now 

 that a telegraph extends over so large a part of the northern hemisphere, we are 

 in a much better position than ever before to complete our knowledge of the 

 laws that govern the movements of these vast air currents. Observation has 

 already shown that the lateral displacements of these broad air currents are 

 intimately connected with each other, but we are still completely ignorant of the 

 laws that regulate their distribution in longitude, and why in some seasons they 

 occupy continuously broad portions of the earth's surface whilst in other seasons 

 they seem to be constantly mixing, both vertically and laterally, on the same 

 portions of the globe. As to the breadth of these currents, they undoubtedly 

 vary in different seasons. This year the breadth of the Polar current, on this 

 continent, would be about 1,200 miles, whilst the Equatorial current to the east 

 extended from the western border of the Mississippi Yalley to the Atlantic. 



I regret not having the data to compare the rainfall at different points of the 

 continent for the years 1861-2 and 1863-4, two of the most marked seasons we 

 have had. I have brought the subject before the Academy in this imperfect 

 state in the hope of attracting more attention to this particular branch of 

 meteorology. 



Dr. Behr presented a piece of wood of an unknown kind from 

 Mexico, having the odor of the " Lemon Verbena " (^Aloysia) and 

 the East Indian Aquilaria, a valuable wood. 



