Discussions continue on this subject, and even in well informed channels the arguments go on as if nothing had been learned. Surely it is a gain to know as we do from the work of Prof. Penhallow, that in all cases of peach yellows there is a deficiency of potash in the wood. It is also a gain to know, for certainty, that the disease is confined to a certain latitude - that it does not exist in the Southern States. This last statement is open to an argument on strict construction. The Editor believes he has seen it in a lew cases South - but be this so or not, it is incontestible that at least it is extremely rare there. These being certainly facts, we have surely learned something. The disease cannot be simply starvation, because there is as poor peach land, and as much neglect of trees South as anywhere. And as we find a want of potash in trees, where the soil abounds in potash, the inference must be undeniable, that it is the vital power of the tree that is affected. We have certainly learned - thanks to the labors of scientific observers - that, to discover the cause, we must search for those influences that affect the life of a tree.

It is certainly a great gain, to be brought within so small a circle.