Professor Phillips, of the Western University, recently lectured in Pittsburg on the "Absorption of Poison by the Roots of Plants." If these poisons become soluble the roots will absorb a little, but the plant will die after such absorption. In that case the poison would be found in the tissue. If it be not soluble the plant may grow in the midst of poison and yet have no poison in it. Paris green, for instance, is not soluble, so there can be no poison in a potato where Paris green has been used for insects.