THE IRRIGATION AGE. 



IT is a common saying among farmers and others 

 interested in temperatures at various seasons 

 that the United States weather bureau thermometers 

 scarcely ever indicate so low a temperature during a 

 cold wave as do private instruments in the locality. 

 The cause of this conservatism on the part of the 

 government thermometer is generally believed to be 

 that it is a more reliable instrument, and has been 

 graduated and tested with greater accuracy. Two 

 observers, independently of each other, have made 

 experiments in this direction which are worthy of 

 note. One of these observers was located at Pasa- 

 dena, in Southern California, and the other at Sac- 

 ramento, the capital of the State. All government 

 observers are expected to have their thermometers 

 sheltered in a certain way, prescribed in the rules 

 and regulations governing the weather service. In 

 accordance with this requirement, the observer at 

 Pasadena, Mr. H. S. Channing, had one thermometer 

 placed 7 feet above a platform 12 feet square on a 

 roof 32 feet above the ground. This was for the reg- 

 ular daily observations reported to the government 

 bureau at Washington. A similar instrument was 

 placed 5 feet above the ground on a post 5 feet away 

 from the house and on the north side. The instru- 

 ments were read at 5 and 8 in the morning. Mr. 

 Channing sums up the matter as follows : 



" The results of the observations taken on clear 

 and comparatively still nights gave an average dif- 

 ference of 1.6 degrees lower temperature for the ther- 

 mometer nearest the ground, the difference varying 

 from 0.4 to 4.2 degrees. This last variation of 4.2 

 degrees occurred on one of the coldest and stillest 

 nights of the month." 



The observations at Sacramento by Mr. S. H. 

 Gerrish disclose a condition of things somewhat un- 

 usual. In this connection Mr. Gerrish says: 



" The idea has prevailed that a frost would do 

 more damage in wet weather than when it was dry, 

 and the irrigation of orchards has been suspended 

 to 'harden the trees.' I experimented years ago 

 and found to the contrary; that the damage was 

 severe only when the ground was dry, the cause being 

 that the northwest wind was negative in its electrical 

 effect and sapped the positive or life-giving electricity 

 from the plants. This weakened the vegetation so 

 that a lighter frost would damage the plants more 

 than a heavier frost when there was plenty of moist- 

 ure.'' 



Mr. Gerrish also presents an exhaustive table 

 showing a comparison between the minimum tem- 

 peratures at Sacramento, as indicated by two equally 

 accurate thermometers, one of which was placed 



some distance above the ground, as required by the 

 weather bureau, the other being near the ground. 

 The period covered by the observations was eighteen 

 years, and ranged through the months of January, 

 February, March, November and December of each 

 year. The number of observations recorded is 463, 

 in which 17 show that the thermometer nearest the 

 ground registered a higher temperature than the 

 other, and 12 observations show an equal registry 

 for both instruments. In all other cases, 434 in num- 

 ber, the instrument nearest the ground showed a 

 lower temperature. The average difference in read- 

 ings for all observations was 5 degrees, showing that 

 killing frosts might be safely assumed to follow a 

 weather bureau record of 37 degrees. But the differ- 

 ence was very much greater in numerous instances, 

 and reached in one case 14 degrees, and in another 

 (Dec. 18, 1892) 16 degrees. In the latter instance the 

 weather service thermometer recorded a temperature 

 of 40 degrees, while the one near the ground fell to 

 24, a most remarkable difference. In another case, 

 when the government instrument showed a record of 

 45 the other registered 31 (on Feb. 17, 1881). It will 

 thus be seen that under ordinary conditions the 

 records of temperature given by the government 

 weather service are by no means an infallible guide 

 to farmers and fruit-growers, and have no doubt 

 given rise to much complaint of the inefficiency of 

 the service. 



Assuming that the raison d'entre of the weather 

 service is to aid the farmer and fruit-grower in con- 

 nection with other important interests, it is here sug- 

 gested that a great improvement might be made by 

 having two thermometers at each observer's station, 

 the one placed as now, but the other exposed in such 

 manner as to record as nearly as possible the actual 

 temperature prevailing at or near the ground, such 

 as growing crops would necessarily be exposed to. 

 The trouble and expense attached to this addition to 

 the service would be insignificant, and much good 

 could be made to result. The agriculturist is not 

 especially concerned about weather conditions in the 

 atmosphere many feet above his crops, but he is 

 deeply concerned to know very often what degree of 

 cold he may expect at or near the surface of the 

 ground at a given time. 



In view, therefore, of a condition which appears 

 fully established by the observations made in Cali- 

 fornia, THE IRRIGATION AGE would respectfully 

 invite the attention of Secretary Morton to this mat- 

 ter, with the hope that further investigation be made 

 to the end of improving the service along this line. 



California fruit-growers have demonstrated that 

 irrigation does not produce fruit of inferior flavor 

 but that too much water does produce lack of flavor. 



