Bitter Pit in A'pples. 375 



for since mercury is a general protoplasmic poison, once it 

 enters living protoplasm in a soluble form it cannot fail to 

 exercise a poisonous action. 



Do Apples accumulate and permanently retain 

 Mercury from dilute solutions P 



To determine this, six peeled quartered Jonathans, having a 

 total volume of 820 c.c, were immersed in 6 litres of a 1 per 

 10,000 solution of mercuric chloride for one week until browned 

 right through. The fact that the browning took place in the 

 presence of mercuric chloride seems to show that it is not the 

 result of the action of an oxidase ferment, but is the result of 

 direct oxidation upon substances which either come into contact 

 when the cell is killed or are protected from oxidation while it 

 is alive. 



The Federal Analyst reported that "the sample submitted for 

 analysis has been found to contain approximately 50 milligrams 

 of mercury compounds, calculated as metallic mercury. For 

 the total bulk this represents 204 milligrams of mercuric chloride 

 not removed by washing, but held in more or less permanent 

 combination." 



The residual solution, after the apples had been removed, waa 

 too dilute to test for mercury by volumetric means. It turned 

 slightly brown with sulphuretted hydrogen, but formed no pre- 

 cipitate ; it gave no opalescence with ammonia, and there was 

 no perceptible change of colour when an excess was added to a 

 lOOGth normal solution of potassium iodide. Hence, to deter- 

 mine the amount of mercury present, a clean strip of pure 

 copper was immersed in 1000 c.c. of the liquid. It took three 

 weeks before all the mercury was deposited. The copper strips 

 were weighed before and after heating in an atmosphere of 

 hydrogen, the decrease in weight giving the amount of mercury 

 deposited. One litre contained 38 milligrcuns of mercury, or 

 47 of mercuric chloride. Hence the apples had apparently ab- 

 sorbed approximately one half of the total quantity of poison ; 

 that is, 318 milligrams or 388 milligrams per litre; that is, 

 three to four times the original concentration in the liquid outside 

 Hence the pulp cells of apple« are able ro accumulate such 



