226 TRANSACTIONS OF THE 



METEOROLOGICAL REPORT. 



BY THOMAS M. LOGAN, M. D., METEOROLOGIST TO THE STATE BOARD OF 



AGRICULTURE. 



In continuation of the plan adopted from the commencement of these 

 reports, the Meteorologist to the State Board of Agriculture herewith 

 submits another series of tabulated results of obsei-vations made in 

 diverse localities in the State. As every additional year adds to the 

 value of these tables, b} T bringing the general averages nearer to a con- 

 stant, so it becomes necessaiy to recapitulate, in a measure, our former 

 calculations and deductions, in order to make the resulting corrections 

 in the right place. The busiest farmer can thus, at a glance of this com- 

 pact mode of information, get all the essentials we now possess, and be 

 prepared to study the details of any part or parts he may wish further 

 to examine while concerting his plan of operations with intelligence. 



The tabulated series of the results of the thermometer and rain 

 gauge, especially at Sacramento and San Francisco, may be made the 

 basis for estimating these chief items of what constitute climate (except 

 where other special observations have been made), in the great interior 

 valley portion for the former, and the coast valleys for the latter. The 

 mean temperature of each month and year for the whole period observed, 

 together with the extremes of heat and cold in each month and each 

 year in these important localities, can be readily contrasted. To facili- 

 tate the comparative estimate of a more extended area, a recapitulation, 

 with the latitude, longitude, altitude and mean annual amount of rain, 

 has been expressly framed, including all the localities whence I have 

 been able to collect the data. These contrasted summaries show how 

 irregularly isothermal localities in the State are distributed, and also 

 how widely the nearest approximated points are thermall}- distinguished 

 from each other. It is also seen that while there are but few places in 

 which the precipitation of aqueous vapor is approximately the same, 

 there are many in which the difference is remarkably striking. Refer- 

 ring to the tables of mean temperature, it will be seen that San Francisco 

 has no summer, or if it comes at all, it is when the summer months have 

 passed by. September is there the warmest month in the year, and 

 October next. Jul}', the hottest month in Sacramento and elsewhere, 

 is the fourth in the order of heat in San Francisco. From the tables of 

 the extremes of heat and cold, it appears that the coldest weather ever 

 experienced since the American settlement of the State, was in January, 

 eighteen hundred and fifty-four, when the mercury fell to twenty -five 

 degrees in San Francisco, and nineteen degrees in Sacramento. At that 

 time, the mud in the streets of both these cities was all day frozen solid. 

 At Sacramento the slough was frozen over a whole day, so that one 

 could walk over the edges of it. Such remarkably cold weather, however, 



