No, 200,] 119 



I reply ihat in each of these years the disease appeared in various 

 fields in the United States. In 1832 my potato field first exhibited 

 evidence of disease in the leaves and stems, which I have often seen 

 since. The leaves first curled up, presenting a grey color vv^hich ra- 

 pidly changed to a darker hue, and without frost or any known cause, 

 prematurely perished. But the potatoes, although a smaller crop than 

 usual, did not shew anydisease. That summer was distinguished by the 

 first visit of Asiatic cholera in the United States. It ravaged this city 

 taking off eight or ten thousand persons of all the various ages, sexes 

 and conditions, I then inclined to ascribe the potato disease to the 

 same evil influence, as we are very apt to select always proximate 

 causes. Since that time the disease has appeared in Europe and 

 America, in every variety of soil and climate, in moist and in dry, low- 

 land and upland situations, yet remarkably, in adjacent lands, ap- 

 pearing in one and not in another, very much as was the appearance 

 of Asiatic cholera. I therefore answer that I am at a loss for any spe- 

 cific cause of this disease. 



Question second — Did the potatoes, which were sound when dug, 

 remain sound, and were any means of averting the corruption of the 

 root, after it had been taken out of the ground, found effectual ? 



I reply, that it is established that the starch in potatoes is readily 

 extracted from those diseased as well as from the sound, and that this 

 is the only sure method of preserving the farina. But it is believed 

 that where the diseased potato is placed in contact with lime, the dis- 

 ease is entirely arrested, so that on cooking the diseased potato which 

 has been limed, the diseased part readily separates from the sound 

 part. The experiments of Col. Edward Clark of Brooklyn, in this 

 matter, are satisfactory to me. 



Question third. — Was it found that potatoes and other vegetables 

 or grains, planted in ground where diseased potatoes had been grown, 

 were attacked by the same disease ? 



I reply, that in fields where potatoes have been diseased in one sea- 

 son, those sound ones selected from the diseased crop have been plant- 

 ed in the same field, and have this year yielded sound potatoes. And 

 recently potatoes were exhibited by Mr. Lodge, a gardner of West- 

 chester, of as perfect a character as ever known. And that his method 

 is to till the soil with the most perfect care, making thorough clean 

 work of it, following Toll's theory of deep and constant tilling. 



