The Six Ericsson Batteries

Captain Ericsson lias contracted with the government to build six new Monitors. They Will ba constructed )ii the general plan of the Monitor, though it i.s unnecessnry to state that in the building of 1 he DOW véasela each one will have peeulianties of its ovvn. Thoy v i ï 1 be mueh inore powerful than the Monitor, though built on the same principie, iáomo of them will be about ÖOO feet in lungtt), whilo the Monitor is only 170 fttet long - a diífurence of 130 feet in favor of tlie new ones. These will be by lar the most powerful vessels on the ocean. It is not deemed expeilient to publish the details of their plan now, but it is sufBcient to know that a vessel of this size, armed with a ló-incli cun, throwintt a shell cf a thnusnnd pounds weight, could very oaeily eink the Warrior r Gloire. - Ea:h will be oí' 1,085 tons burden, 1,450 tons displacement, and 11 feet drai't. Thoy will ba armed with two 15 inch gnus, and the contract prioe is 400,000 eucli. Several deficieücies in the will be rectified in these batteries, the pilot house being placed on the revolving turret, and ventilütioo passing througli the roof of the latter instead oí through tbe deck. The tur rots are 21 fuet in diameter, and 11 inches tliick - which is 3 inches thieker Uum the Monitor's. Thcir speed will be ten miles per hour. The platea are being rolled 10 Maryland and Pennsylvania. A.11 the rest of the iron ior frames, fastenings, etc, amounting to scveral thousand tons, is being made by Corning, Winslow & Co. and the Keusselaer Iron Company, at their works in Troy. Four of tbevessek are to be completod by the lst of August, and two by the lst of September. - Some tvventy-eight hundred men are at work uj.on these six vessels, and it i? oonfidently beüeved by the contraetors Unit tboy wilt have thern cornpleled vrithin the stipulated time. The ivhole sis are intended for sea service as wcll as for the protection of harbors. Il is a mistaken idea to suppose that these vessels are uufit for long voyages. The run of the Monitor to Hampton Iloads, as far as it proved anythirg, seemed to vindícate the opposite as the truth. Tbere were sotue diffiüulties with trilling matter, suchas the water breaking over the snioke-stack and leaking through the deck, but otherwise the Monitor proved herself a good sea-going boat. Captain Ericssoti claimod for her that ehe could live ni a sea vyhere any otber vessul could livi', as she is constructud on the principie of the life-boat, and we have not heard of uiiything to invalídate thu truth of his theory iu regard to her. Nothing bas happened to strate that the Mcnitor eould not make a vpyáge to Europe vvith perfect safety, althoügh we don't know that any such ability is cluimed lor her. The greatest difficuhy woukl bo thit tho crew would have very dark and close quarters in the cabin. The models oí the new Monitors ar slightly altered to make them much better sea boat, and to givo them groater speed, 'l'hoy will be propellers, like tho Montior, with deck close to tho water !in3. The three gnnboats whiuh are being built by Mr. Rowland, at the Continental Works, Greenpoint, will difter from the others in having two turrets. The frames, we believe, are entirely of ron. Their length will be 302 feet over all, with a bread th of beam of 41 foet, and n ilepth of liold ol 12 ieet. - Tbo annor 13 to bu six inches in thiokness. The work is well along on all of tbem. Tho plating is going on as fa.st as poBRÍble. The irnn riba and platos are torged m n separate workshop, but small foTjjfa aro pet up round about fof he.iiting tho bolts. As largo :i crew cf men as can work tvith convenence are busily engagod Q riveting tho plates.