A NEW DANGER.
A new element of danger has been discovered by the insurance inspectors of Boston, into which electricity enters. This new risk is found in metallic sodium, which forms on electric wires, and which, when moistened and struck with any bard substance, gives off flashes of fire. It looks not unlike discolored salt, is slippery to the touch and very corrosive. The substance was carefully analysed by expert chemists and declared to be metallic sodium. This substance is very hard to obtain except by means of electricity. It is very combustible, and when it unites with water hydrogen gas is given off, and under certain conditions a certain amount of heat, which might be sufficient to ignite the hydrogen gas. As is well known, hydrogen and air in certain proportions form a very explosive compound, and it is just here where the danger is hidden. The metallic sodium present inthis case was due to electrolytic action on impure sodium hydrate which came from the mortar used in the brick wall. It is more than probable that several of the explosions in underground conduits were due to this cause. Metallic sodium is an excellent conductor of electricity.