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action. These qualities — sensitive sympathy, wise prudence, constancy 

 — were those which pre-eminently characterised him as a man, and 

 made him to those who knew him a friend of rare worth . 



In the history of science Mr. LasseU's name will rank with those of 

 Herschel and the late Lord Rosse in connexion with that essentially 

 British instrument, the reflecting telescope, whether we consider the 

 genius and perseverance displayed in the construction of these instru- 

 ments or the important discoveries which have resulted from their use. 

 About 1820 Mr. Lassell, then in his twenty-first year, began to con- 

 struct reflecting telescopes for himself. It is perhaps to circumstances 

 which he at the time considered unfavourable, that science is indebted 

 for much that Mr. Lassell has accomplished. At that time he did not pos- 

 sess sufficient means to enable him to purchase expensive instruments, 

 and besides "his business avocations were such as most men consider 

 of an engrossing nature." The value to him in his subsequent work of 

 the energy and power of resource which were in this way so strongly 

 developed in his character at an early age, it is difficult rightly to 

 appraise. His success with the first two instruments, which he 

 attempted simultaneously (a Newtonian of seven inches diameter and a 

 Gregorian of the same size), encouraged him to make a Newtonian of 

 nine inches aperture. The instrument, which was erected in an observa- 

 tory at his residence near Liverpool, happily named Starfield, may be 

 said to form an epoch in the history of the reflecting telescope, in conse- 

 quence of the successful way in which Mr. Lassell, on a plan of his 

 own, secured to it the inestimable advantages of the equatorial move- 

 ment. The several mirrors made for this instrument were of great 

 excellence. The observatory note-books of the late Mr. Dawes, which 

 are in the writer's possession, bear record to the delicate tests for 

 figure to which these mirrors were put on the occasions of the frequent 

 visits of Mr. Dawes to his friend's observatory. With this instrument 

 Mr. Lassell diligently observed, and detected, without knowledge of its 

 existence, the sixth star in the trapezium of the nebula of Orion. This 

 instrument is fully described in the twelfth volume of the " Memoirs of 

 the Royal Astronomical Society." 



About the year 1844 Mr. Lassell conceived the bold idea of con- 

 structing a reflector of two feet aperture and twenty feet local length, 

 to be mounted equatorially on the same principle. He spared neither 

 pains nor cost to make this instrument as perfect as possible, both 

 optically and from the mechanical side. As a preliminary step, he 

 visited the late Earl of Rosse at Birr Castle, and commenced the 

 specula for the new instrument upon a machine similar in construction 

 to that employed by that noKleman. After some months' work, he was 

 not satisfied with this apparatus, and was led in consequence to contrive 

 a machine for imitating as closely as possible those motions of the 

 hand by which he had been accustomed to produce perfect surfaces on 



