iron-limbed Samson wrestling with mighty bars of metal, and twisting and tearing them across the grain like bits of stick. The fractured remnants of the specimens and of the guns rent in the testing process in the Marshes and at Shoeburyness are collected in a museum, the history of each specimen being minutely given. Thus a curious and instructive record is gradually being acquired, which will prove of infinite use in the manufacture of heavy ordnance. It has been already ascertained that guns are universally strengthened by having wrought iron rings put round them--a fact which was discovered during the course of experiments with the heavy cannon bored with an oval rifle to receive the Lancaster shell. Several of them having burst at the muzzle, this simple expedient was tried, and the guns so girded now bear the most extraordinary charges without flinching. The new building for casting, boring, and finishing iron guns, is both externally and internally the most imposing-looking of all the structures erected to meet the exigencies of the Crimean war. These spacious factories present more the appearance of first-class railway termini than of ordinary workshops. They are lighted with what are termed saw-roof lights, having a northern aspect; for the Vulcans who can work all day in the burning blaze of furnaces do not, it appears, like to be distracted with the confusing rays of the sun! The number of turning, boring, finishing, planing, shaping, drilling, slotting, and punching machines that revolve, thump, and slide here in ponderous grandeur is prodigious, and there can be very little doubt that it will be the most perfect and powerful factory in the world of its kind. Travelling-cranes, which run upon railways poised in air overhead, command every inch of the factories, so that cannon of the heaviest calibre for both land and sea service--98-pounders weighing many tons can be slung from machine to machine with the greatest ease. When the machinery is completed, the foundry will be capable of turning out ten guns of the largest size per week.