STATE AGRICULTURAL SOCIETY. 311 



The Cold Wave. — Records of Three Sacramento Observers at Dif- 

 ferent Points in the City. 



The following interesting tabulated matter during January last shows 

 the lowest temperature recorded by self-registering instruments in different 

 parts of the city. Captain Foster, of the steamboat company, has his ther- 

 mometer at his residence, southwest corner of Eleventh and F Streets. It 

 is a Green's standard signal service self-registering instrument, and is 

 exposed under a grapevine arbor about five feet from the ground, in his 

 back yard, the two-story house breaking (somewhat) the force of the north 

 winds. 



S. H. Gerrish's is a Sixe self- registering thermometer, manufactured by 

 Hicks, of London, England, and is situated in his back yard, at No. 1817 

 G Street, being on the north side of the street. The thermometer is exposed 

 to the full effect of radiation to the sky, there being no covering over it, and 

 is in the back yard subject to the full force and effects of the north winds, 

 which are cold in winter and hot in spring, summer, and fall. Mr. Ger- 

 rish's thermometer is about five or six feet above the ground. 



The Signal Service thermometer is a Green's standard minimum, self- 

 registering instrument, exposed on the roof of the Signal Office building, at 

 No. 117 J Street, sixty-one feet above the ground, and is in a single latticed 

 shelter, Signal Service pattern. The wind blows through the shelter in aU 

 directions. 



The table below shows that during the thirty-one days of January there 

 were but two upon which each observer recorded the same minimum tem- 

 perature, and singularly, too, the minimum temperature was the same on 

 both the days, being 34° on both the twelfth and nineteenth. The wind 

 was north, blowing nine miles per hour, and weather cloudy at 4 A. M. of 

 the twelfth; and southwest, four miles per hour, and weather cloudy, on 

 the nineteenth. 



Captain Foster's record and the Signal Service record were the same 

 on eight days, as follows: Twelfth, 34°; thirteenth, 32°; seventeenth, 22°; 

 nineteenth, 34°; twentieth, 38°; twenty-first, 41°; twenty-third, 49°; twenty- 

 fourth, 42°. There were but three days upon which the records of Mr. 

 Gerrish and the Signal Office coincided, those being the twelfth, 34°, nine- 

 teenth, 34°; and twenty-second, 45°. 



The average difference during the month was as follows: Captain Foster 

 1.8° lower than the Signal Service, 1.1° higher than Mr. Gerrish; while the 

 records of the latter gentleman show an average difference of 2.9° less than 

 the Signal Service, and 1.1° less than Captain Foster. 



There were sixteen days in January that were cloudy at 4 a. m. The 

 average minimum temperature for those sixteen cloudy days at the above 

 hour, was: Foster, 39.9°; Gerrish, 39.8°; Signal Service, 41.6° — making the 

 latter only 1.7° higher than Foster, and 1.8° higher than Gerrish. The fif- 

 teen days that were clear or fair at 4 a. m., show an average minimum of 

 20.9° for Foster, 25.3° for Gerrish, and 29.5° for the Signal Service, making 

 the latter 2.6° higher than Foster, and 4.2° higher than Gerrish. The great- 

 est difference (6°) between the readings of Mr. Gerrish's thermometer and 

 that of the Signal Service, occurred on the seventh, eighth, ninth, and six- 

 teenth. At each time the wind was from the north, and gentle in velocity, 

 and calm on the eighth. The weather was clear each day. 



The least difference was 1°, on the first, fourteenth, twentieth, twenty- 

 first, twenty-fourth, and twenty-sixth. The weather was rainy or cloudy 

 on each day, except on the fourteenth, when it was blowing briskly from 



