A Bar Of Platina

The Paris Mint has just completed the manufacture of a bar of irradiated platina of the enormous weight of 500 lbs. and worth 210,000 francs, the exhibitiou of which recently took plaue in the Conservatoire des Arts et Métiers of Paiis, in the presence of delegates from foreign countries'and members of the Academy of Sciences, invited by General Morin, director of the establishment. The ruass of metal, quite exceptional for its size and homogeneousness, is to be used in making the standard meters and kiloLrauis required by various governinents 'or the adoption of the metrical system, or the comparison of their weights and meaBures. Ëach set will cost 3,000 francs, and forty-five have been ordered by the different powers. The fusión of tho metal was effected by the aid of seven blowjipes of oxhydrogen gas inserted in tho sover of an enomous crucible ; forty cune meters of that fluid wore sufficient to teep up the combustión of the seven jets ! of ordinary gas during the two hours ,he combustión lssted. The light of the i ncandescent metal was bo intense that ! ,he melting pot could only be looked o with the aid of a colored glass. Many entuñes may pass before the occasion ! hould arise for suoh a work as that exeuted, as tho production of platina is very imited, and does not exceed from a ton j ;o a ton and a half annually.