Cuttings of Willow, the lower ends of which were placed in flasks containing a little water and filled with coal gas, developed only short roots, and the buds on the upper parts died shortly after unfolding in the air. Of ten plants in pots (varieties of Fuchsia and Salvia), among the roots of which coal gas was conducted through openings in the bottom of the pots, seven died in four months. To show that the plants were killed, not by the direct action of the gas, but in consequence of the poisoning of the soil, several experiments were made with earth, through which coal gas had passed for two or three hours daily for two-and-a-half years. The rootlets of seed sown in this soil remained very short and soon rotted. A plant of Dracaena was repotted in the soil; in ten days the leaves dried up and the roots died. These results sufficiently account for the fact, that the trees planted near gas pipes in streets so often die; the closing of gas pipes in wider tubes, having openings to the air, and through which currents could be maintained by artificial means, has therefore been recommended as a remedy.

Such a plan is still to be more recommended on hygienic grounds, since it has been shown than infiltration of coal gas through the soil, takes place even into houses not supplied with gas.- Scientific American.