Letters from various observatories on filling vacancies, the construction of time balls at Sydney and New Brunswick (with a plan), and the establishment of new observatories at Nottingham, Bristol and other locations. The correspondents include J. Challis, Sir W. Denison, C.E. Trevelyan, J.R. Hind, R. Stephenson, C.P. Smyth, C. Pritchard and M.J. Johnson. There are also two reports on Liverpool Observatory, a paper on Brussels Observatory, and a piece from 'Le Moniteur Universel' on the Paris Observatory. |