A VISIT TO GREENWICH OBSERVATORY, in 



the astronomical world has to show, for most 

 Englishmen understand, and are ashamed to confess 

 it, that even Greenwich is behind the age in the 

 matter of apparatus, though certainly not as respects 

 men. But talent, ingenuity, industry, though they 

 can accomplish vast things, cannot supply the lack 

 of the highest and most elaborate machinery and 

 optical powers. 



It may be as well to say here that telescopes are 

 mainly of two kinds. There is the refractor, through 

 which the star or other object is looked at directly. 

 There is also the reflector, through which the star 

 itself is not actually seen, but its image is reflected 

 from a large mirror or speculum up the tube, and is 

 magnified by the eye-piece apparatus. The first re- 

 fractor was the one invented by Galileo, and through 

 it he saw, probably for the first time in human 

 history, the satellites of Jupiter. The largest re- 

 fractor in the world is the one lately erected at the 

 Lick Observatory on Mount Hamilton, in California, 

 the object glass of which is thirty-six inches 

 across. The Russians have the next best refracting 

 telescope, that of Professor Struve of Polkowa, the 

 diameter of which is thirty inches. The Vienna 

 refractor is twenty-seven inches, the Harvard College 

 one is twenty-six inches, and then comes Mr. R. S. 

 Newall's, lately presented to Cambridge, which 

 measures twenty-five inches, and was at the time 

 of its construction the largest in the world. 



The finest reflector in the world is the one of 

 which everybody has heard, that belonging to Lord 

 Rosse, of Parsonstown, in Ireland, whose speculum 



