Bitter Pit in Apples. 401 



One c.c. per 2000. Pits from superficial to 2-3 mm. deep. 



One c.c. per 20,000- Superficial browning to pits 1 mm. deep. 



One c.c. per 100,000 No effect to slight superficial browning. 



One c.c. per 1,000,000. No perceptible effect at any time. 



Ozone. — Each apple (Jonathans and Sturmer Pippins) was 

 placed in a Ih litre gas cylinder, charged with ozone by the 

 silent discharge of high-tension electricity (10-inch spark coil) 

 for two minutes daily for three days^. No perceptible effect was 

 produced except that many of the breathing pores became more 

 prominent. 



The experiment was then repeated, charging three times 

 daily for five minutes at a time for three days (a total of 15 

 minutes charging). The apples were covered with small spots 

 and pits. The latter in one week were 1-2 mm. diameter and 

 2-3 mm. deep. These were almost entirely developed under breath- 

 ing pores, but a few formed under the unbroken skin. Closely 

 similar effects were produced by one charging of an hour's 

 duration. The air was neither acid nor alkaline, and the ozone 

 rapidly disappeared in contact with apples, no trace being detect- 

 able with starch and potassium iodide paper after 10 to 24 

 hours. Neither ozone nor ammonia are, however, likely to be 

 present under natural conditions in sufficient amount, and for 

 a sufficient length of time, to affect apples, except under most 

 unusual circumstances. 



Iodine. — A solid substance which is volatile, may, however, 

 aft'ect apples at some distance. Thus a Jonathan apple was 

 placed in a closed 1-^ litre gas cylinder one foot distance from 

 5 milligrams of iodine. In five days the iodine had sublimed, 

 and in seven days the apple was covered with small dark spots. 

 No smell of iodine was perceptible, but starch paper placed on 

 the apple in the cylinder was tinged faint blue in 20 minutes. 

 After twc weeks in air, some of the spots had enlarged to pits 

 1 to 2 mm. diameter, tind 1 mm. deep. 



On repeating the same experiment, keeping the cylinder closed 

 for 14 days, two weeks later many of the spots developed into pits 

 1 to 2 mm. deep, and a few larger discoloured areas developed 



1 The apples were removed duriiij-- each chargiTiji-, siiit-e the silent discharge if long 

 contimied, produces brown spots and areas of variable deptli, particularly if the apples 

 touch the vflass, or from the point of suspension if this affords a ready jiath for the current. 



