A RECORD TELESCOPE.

Otago Daily Times, Issue 19218, 8 July 1924, Page 8

A RECORD TELESCOPE.

MOST POWERFUL IN EUROPE. Wliat purports to be the largest and m . i powariul rejecting telescope in Europe nua recently been constructed by the hrm of Jena, Germany, and installed at one of the principal (jerinau observatories, tnu: of Keu-Babeiaberg, near Berlin Rotates the Gorman •correapondcnt of ihe Scientific American). This ia surrounded by a huge cupola 13 metres in internal diameter, rotating round ita axis and comprising a slot tiiree metres wide. Apart from the principal mirror, 1251) millimetres in diameter, there are two auxiliary mirrors used alternately, according as the telescope is employed either on tuo Newton or on tuo (laasegrafn system, tire tocal distance being b. 4 metres in the former case and 21 metres in the latter. Broviaion is frw.de for visual and photographic observation a.s well as *or spectroscopic work. Tire aumliary mirror used with the Newton system, is fitted to too Iront eno and into the axis of xne tune by means of two steel bands in its interior. This ia a plane mirror of elliptical outline (4UI) x 300 millimetres),tiie fitting and ailucu ment of which, carries a spherical balancing weight. When arranged on the Newton system for photographic work, the adapter is fiUed'wrtu cross-slide and two spectroscopes, thus allowing tne daily motion of the instrument to be cuecked most accurately. To this front end of the tube can be imparted any rotation round its axis by means of a hand-wheel at the underslide of the telescope, thus' cna bling tne adapter arrangement and the searcher or 100 millimetres opening to be readily attained By tne observer. Electrical button switches to the left of the adapter control the fine adjustment of the instrument. There la also a mechanical line adjustment, independent of the other and simply actuated by means of a hand-wheel, trie reflecting telescope is fitted with a double system of guiding and balancing axes. The balancing axes enable the movable parts of the telescope vo be arranged sideways to the stationary column, thus allowing the telescope tube perfect freeness of motion in all directions.