EFFECTS OF FREEZES ON CITRUS IN CALIFORNIA 



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Fig. 7. On left an orchard coal heater. This is merely an open firebox 

 with grate at bottom. In center, the simplest type of orchard oil heater, 

 being merely an open pail-like structure with holes at top for air draft, 

 on right, a type of torch used in lighting heaters, supplied with asbestos wick 

 and burning distillate or kerosene. Photo by Barrett. 



Fig. 8. On right one of the typos of orchard oil heaters very commonly 

 used at the time of the 1913 freeze, having a sliding top and with openings 

 on the side for air draft. On left one of the best orchard heaters that has 

 been perfected since 1913. The smoke stack and drafts are hidden by the 

 cover which is lifted off when heater is lighted. Photo by Barrett. 



