Charles Sanderson, in a paper recently read before the British Society of Arts upon the subject of Iron, remarks that much has been advanced in favor of the manufacture of ordnance from cast steel, but he does not think that good and serviceable pieces of artillery can be manufactured from such metal. There is no great practical difficulty in casting a mass of steel two or even three tuns weight, but the irregular crystallization of so large a body of steel, melted in parcels of fifty pounds in a crucible is unfavorable to that uniform molecular structure which such castings should possess, since upon their excellence f often depends the issue of a siege or action. Although wrought iron ordnance cannot be depended upon, they are better than cast steel, but their perfection is much impaired by the necessity of piling masses of iron together. He admits that a weld can be perfectly made, but two surfaces when oxydized can never become one amalgamated body, without the oxygen be reduced at the moment when the union is effected. Wrought iron guns have given excellent results when fired at slow intervals, but if a continuous quick firing were kept up, he doubts their being able to withstand the shocks ; they would, he thinks, after each round become gradually weaker through the welded surfaces.