OUR FOREIGN CORRESPONDENCE. (BY ATLANTIC CABLE.) DOWNING STREET, LONDON, April 10, A.M. I have, as ordered, made extensive arrangements for a world-wide correspondence for PUNCHINELLO. Knowing your want of confidence in the party called, so truly and briefly, the "_Press Ass,_" who sends over accounts of horse-races, etc., with an occasional item of news, I have wires connecting this office with Paris, Madrid, Rome, and other places of consequence. A special delegate of PUNCHINELLO has been already admitted to a seat in the OEcumenical Council. Pope Pius remarked kindly that he was the only person there who honestly told what he came for. His Holiness enjoyed, also, a hearty laugh at his first interview; the subject being the proper title and costume of our delegate. It was concluded, as he was somewhat dark in complexion, to dub him Bishop of 'Ngami; which, you know, is one of those places that LIVINGSTONE (_is_ he living, though?) found out. When any body questioned him, the said delegate was immediately to talk 'ngammon Latin; and His Holiness would interpret it to the council, as being the African for infallibility. It's wonderful how well this jolly dog gets on, with his dogmas and dog Latin together. Now for news. After all, the _most_ remarkable event has happened on your side of the water; but as Philadelphia is further from New York than New York is from Philadelphia, (the latter is _so_ slow,) I don't believe you have heard it yet. There is a railroad, well known thereabouts, going to _Germantown._ Well, the event is, that the board of directors of that road have--will you believe it? I hardly do--ordered a _new car_--a palace-car! The way it happened was that, owing to the large use of cattle-cars on the Pacific Railroad, no more second-hand cars could be got for a month or two, bad enough for the directors to buy; and there wasn't a builder in the country willing to make their kind of cars to order. On this side of the "big pond" we have had nothing so laughable as the MORDAUNT case. The charge of the presiding judge to the Prince of Wales has not been correctly reported. I am told that he spoke thus: "Your Royal Highness is advised that, on this occasion, it is not expected that your Royal Highness should tell the truth, unless your Royal Highness pleases; indeed, your Royal Highness is rather advised not to tell the truth. Now, will your Royal Highness, acting under this advice, please to say, whether he did, or did not, ever do any thing naughty?" Some one said to me at the time--are there not _some_ mordants that will dye beyond whitewashing? But I believe that Wales always was moral, is moral, and always will he moral, (Balmoral!) Now, this last assertion I call news! Is it reliable?