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University of California Publications in Agricultural Sciences [Vol. 3 



bears heavy crops (pi. 26), and has been profitable ever since it came 

 into bearing three to fonr years ago. 



The conclusion cannot but be forced that in the exceptions noted 

 lies the secret of the heavy set of fruits. In order to obtain some idea 

 of the climatic conditions obtaining within this orchard as compared 

 with those under Edison conditions we had recourse to what metero- 



90 i — 



80 — 



70 



60 



50 



40 



30 



20 



10 



I I I I I I 



I I I I I I 



23 



MAY 



31 



JUNE 



Fig. 2. Comparison of daily atmometer water loss at four different stations 

 at Edison in 1916. Ordinates, water loss in cc; abscissae, days of the month. 



logical instruments were available to us. "While much more significant 

 results could have been obtained had we possessed more equipment, we 

 feel that our data, while possibly not accurately quantitative, at least 

 are qualitative enough to justify our conclusions. Air temperature 

 and humidity readings were taken by means of a Freiz thermo-hygro- 

 graph. We were particularly interested, however, in the integration 

 of all the climatic factors in their effect upon the plant and for this 

 purpose selected the Livingston white cylindrical porous cup atmo- 



