From the N. Y. Journal of Comruerce. Withiu tha last ten weeks the uricnm ploted véasela built on the Monitor plan have undergone oofmideruble improvement. As the changos necesaarily delayed thu finishing of the shi-i, t w:is diiemed best nut to menlion the fuot u n til thu vrk was endod, whieh it Bearly d at prwant A few daye since (Bb GiitskiM wit taken from tho !nti - nental Iron Works to H'Jiiter's Pcijnt, where he oras put iiuod a marino railvvay to have udditiohül atreogth iin partud to tlie seotions, tha dvidrng line betiveun whiuli was most deletonouslv aftected ty the soa, in tho Monitor and Passaio. The SanLjnrnon, at Oh en ter, Pennsylvania, luis altio heen ulijucted to a thorough preceda of stréogtheping, and even her interior has beun sornewhat remodeled : tho Nuntucket, al Boston, beiiffitted by the nh:ne course of ti-aatment; and tiie Lehigh at Chester, ill lia made even Strooger thnn the nthers. Were it not for pstra work, the ñee'. bnund sonth wraild havo been larger than if is ]}-ut it is lietter that everv iron-clad sent to sou shoyhd be us nea.-ly perfect as possible. Within the nsxt ihree weeks two more im' prognablo uraftfl will bö dispa'ched heneo The Monitor disaster lias thus been tho canse of clianging tho thu details ol llie plan on which tvvo classes of anned lups were built.