III. Description of the Great Melbourne telescope

Abstract

In 1862 the authorities of the Colony of Victoria formed the design of adding to the Observatory, which they were then establishing at Melbourne, a powerful telescope which should be applied in reviewing the Nebulæ of the Southern Hemisphere. They applied through the Duke of Newcastle, then Foreign Secretary, to the President and Council of the Royal Society, for encouragement in this undertaking, and advice as to the best means of carrying it into execution. The subject was not new to that Body. They had been, conjointly with the British Association, engaged, though ineffectually, for several years in trying to induce the British Government to adopt a similar plan. With this object they had appointed a Committee, including several of the brightest names of British Science, to examine the subject thoroughly and recommend the plan which they considered most desirable to be adopted. Subsequent to their report, Mr. Lassell had actually constructed a 4-feet Newtonian, which he was using most successfully at Malta, M. L. Foucault, whose recent death all lament, had invented the silvered glass speculum which bears his name, and Mr. Warren De La Rue had changed Celestial Photography from a toy into a potent instrument of astronomical research. These new facts required new discussion, which was carefully made, but resulted in adopting the former report with little change. In consequence the legislature of Victoria, acting on the recommendation of our Pre­sident and Council, voted in 1865 the requisite sum; and Mr. Grubb undertook the con­struction of this gigantic equatorial, under the direction of a Committee consisting of the late Lord Rosse, Mr. Warren De La Rue, and myself. After Lord Rosse’s death, his son, the present Earl, was nominated to succeed him by the President. The instru­ment has been very successfully completed; and we hope that a detailed account of its construction will be acceptable, both from the interest which belongs to the accomplishment of a great undertaking, and because, though the late Lord Rosse and Mr. Lassell have published their methods of making large specula, the subject is by no means ex­hausted, and anything which lessens the difficulties which still beset it, and makes the use of large reflectors more attainable, cannot but tend to the progress of some of the most interesting branches of astronomy.