26 Zinc Labels for Trees. 



hills where a part of the tops were green and flourishing; 

 but I think if all the tops had been closely examined, some 

 one would have been found affected, and that one communi- 

 cating with the very tubers which were rotten. I am fully 

 convinced, that the disease is caused by the fungus in ques- 

 tion, and that it first attacks the stalk. 



In the remarks of Professor Playfair, in his Lectures de- 

 livered before the Royal Agricultural Society, in London, 

 reports of which were published about a year since, he at- 

 tributes the disease to the destruction of the cellular walls of 

 the tuber, and in this he follows Liebig, the scientific German 

 chemist. But this destruction of the cells, it appears to me, 

 is not the pi^imary cause of the disease, but an effect, as I 

 have already stated, of the penetration of those cells by the 

 roots of the fungus. Most of the phenomena described by 

 both the above gentlemen, may be discovered attending the 

 disease; but its true cause lies behind those phenomena. 

 That there is any constitutional weakness affecting the cellu- 

 lar tissue of the potato, I am inclined to doubt. We have had 

 peculiar seasons, both here, and in Europe, for the past three 

 years ; seasons which have been highly favorable to the gene- 

 ration and propagation of Fungi, and they have been remark- 

 ably abundant every where. It is these fungi that have at- 

 tacked the potato, and produced the disease. I believe its 

 prevalence to be owing, or attributable, to the peculiar state 

 of the atmosphere ; and that no specific, or infallible remedy 

 for the disease, has been yet discovered. It may disappear 

 in a few years. A change in the atmosphere may render the 

 reproducing spores of the fungus inert for a time sufficient to 

 destroy them, and this may check the disease. - 1 indulge in 

 no apprehensions for the future. A merciful Providence 

 watches over us all, and in his goodness we may safely trust. 



West Scituate, Mass.. Dec. 1846. 



Art. IV. Zinc Labels for Trees. By J. Owen, Cambridge. 



In the last number of your Magazine, you have described 

 a kind of label for trees, which comes near enough to a 



