WITH reference to the scheme of international simultaneous observations proposed by the War Department of the United States and adopted by the Meteorological Congress at Vienna in September last, a provisional arrangement was entered into at Vienna, between General Myer and myself, at his desire, by which the Scottish Meteorological Society was to assist the American Government in carrying out the proposed scheme by an exchange of meteorological observations between the two bodies. At a meeting of the Council of this Society on February 9, a letter was read from General Myer, dated January 27, 1874, formally requesting the co-operation of this Society in carrying out the international scheme, which letter being identical with the one on the same subject published in NATURE (vol. ix. p. 300), it is unnecessary to subjoin.