THE EXPOSITION OF POSTAGE STAMPS. A splendid exhibition of postage stamps will open at the Palpia des Arts Libpraun on the Champ de Marg next week. It is undoubtedly the finest of its kind ever made, and some of the exhibits are not only highly valuable, but wonderful'y complete. That the exhibition will be large'y visited, is beyond all doubt. Unfortunately it is to ba feared that the collection par excellence—that of M. Philippe de Ferrari, son of the late Duchess de Galliera, estimated at 3,000,000fr., will not be on view ; bat the aficionados are sure to find enough to admire and to interest them. In this connection it may be mentioned for the benefit of some ardent collectors that next m order to M. <'c Ferrari, the Czar Alexander 111. the Prince of Wales, the Duke of Edinburgh, Baron Arthur de Rothschild, Mr Philbrick Q.C., of London, Dr Legrand oF NeuiUy, President of the Committee of the Exhibition, besides many well known Americans, Frenchmen and Englishmen, are among the prominent philatelists "known. THE GREAT TELESCOPE. The grand clou of the Exhibition of 1900 is M. Deloucle's idea of making an immense telescope. That gentleman believes m the possibility of constructing the gigantic instrument, which is to be forty yards m length, nine feet ten inches m diameter and nineteen and a half inches thick. It will weigh nin? tons, and is calculated to cost two and a half million francs. M. Deloncle thinks the only difficulty will be m making the great concave mirror, which is to be furnished by the St Gobain Glass Works The largest disc yet made weighs only twplve hundredweight, whereas the one it is proposed to make must weigh several
tons. Thfl magnifying power of thn projected instrument, it is expected, will be fifteen thousand times more thon th« lp.rgpst telescope yet niaito, so that it will bo possible to perceive on t!ie moon objects no bipgrrthan twenty one fqnare feet. Thus we shall ho nb'e to discover whether tho moon i 9 inhibited, fnr al though the instrument will not, be po've.r Ful enough to reveal ions the inhabitants (assuming their statue to be the same ns ours) it will show their residences, palaces, temples, town halls, gao 1 ?, etc. The enthusiastic astronomer, M. Flamraanon is well disposed /oward3 the construction of M, Deloncle's telescore, m fact he has written as follows m his ' Astronomic Populaire ' : — This interesting question of the inhabitants of the moon might be settled m our day, as might many others by a powerful telescope, the cost of the construction of which would not certainly exceed a million francs,'