The Potatoe Plague. 83 



is twice as heavy as the healthy, which he attributes to the 

 presence of a parasite. The loss of starch amounts to twenty 

 per cent. There is present an azotized matter, having the 

 same composition as fungi. All the chemical phenomena 

 point to the action of such parasites, and not to spontaneous 

 fermentation. Messrs. Girardin and Bidard, on the other 

 hand, deny the presence of parasites. They find no other 

 indication of their presence than what occurs in all cases of 

 fermentation. They regard the disease as the result of sim- 

 ple fermentation, induced by the unfavorable season. They 

 recommended perfectly rotten potatoes to be crushed in tubs, 

 to be thoroughly washed, by which means the foul odor is 

 removed, and then, after draining, to be pressed into cakes, 

 which may be dried in ovens after the bread is withdrawn, 

 and given to cattle. M. Durand attributes the disease to 

 atmospheric causes, favored by local circumstances. He 

 knew it in former years, when potatoes were grown in damp 

 places. He denies the statement that the stems were always 

 affected before the tubers, and he states that dryness and 

 darkness are certain safeguards for the crop. Three hundred 

 Hectolities have been thus preserved for a month without 

 change, and yet they had not been very carefully sorted. M. 

 Gerard adverts to the admitted fact that the disease attacked 

 the potatoes between the 10th and 15th of August. He is 

 opposed to the idea that animal or vegetable parasitism is 

 connected with it as a cause, and he ascribes the disease to the 

 presence of a brown matter " which seems to glue the starch 

 grains together, and to prevent their separation." He at- 

 tributes its presence to unfavorable atmospheric causes, which 

 caused the nutritive fluids to stagnate, and thus produced an 

 alteration which ended in decay. 



A Mr. Spooner has published a pamphlet which is chiefly 

 addressed to the question of converting potatoes into starcho. 



