Ou Sunday, February 28, tho pneumatie mail system was oponed for public use in the city of Vieiina, and for the terw days of its working ifc arpeara to have boen eminently satisfactoiy. By tliis method, letters aud paokagos, not exceediug two ounces in woight, can be sent fvom one end of the city to the; othcr j - a tlistanee of about eight miles - in soinething loss thau two seconde, so that, adding to this Üie time neceaary fox making up packages, ing them, and deliveriug them, the whole ia just about an hour. But tliis only covers e. treme distanoes, and managers oí tliis system in Vieuna say that in a short time the time betweejQ receipt and delivcry will be greatly reduced. In fact, between stations only two or three miles distant from each other, such packages i are even fctow delivered witliin twenty minutes after beirig depositad. Any Postmnster in tho city, or Fostmaster(ienenil, who would inaugiirate such ft reform in the local mail arraugemeuts of the metropolis, might acchieve immortal fame. As the general Pcjstoflico in Vieuna is also in the building of the general telegraphic office, powerful steam engines are constantly at work compresging atmospheric air in a mammoth reervoü', from which the doublé system of cast-iron pipes, laid three feet under the ' surf ace of tho streets, are f cd. One syRtem of pipes serves for carrying paekI ages, and the other for pushing them : ahcad in the other directioii. At the seven principal stations, in various parta of tho city, similar engiues are kept at wbrk diiy iind oight drawing the air from the pipes and creating a vacuüm in front of the packages, which are thns more rapidly prewsed forwafd by the expansive force of the compressed air behiud them. The sixty sub stations are connected not only with the two central offices but also witli each other by tliis doublé system of pipes. The dispatch of eacb package is anuounced by telegraph to the office to which it is sent, and to all intrrvening offices to ailvise the lattcr hot to stop it on its way. The pipes aro six inchea in diameter, with a perfeetly smooth iol-' : islied inner surf ace, and the packages aro made up in India rubber cylmders, of va' rious lengths. The postage on mail matter must be prepared ;it the rute of two kreutzei'Sj one cent, for each half ounce or fraction, which is ovidently muoh oheoper thau the two cent postage for city letters iu this country. This is the first instance of a largo city - Vieuna has about 900,000 inhabitants - giving its people such faeilities of correspondence at moderate opat.