DE MORGAN'S ACCOUNT OF WRIGHT'S SPECULATIONS 203 



regulated even his ordinary expressions. It is not often, 

 in his day, that we find, as in his works, the planets 

 described as the known planets, implying an assumption 

 that there might be more. He gave the theory of the 

 milky way which is now considered as established, con- 

 tended for what is now called the central sun, inclining 

 strongly to the belief of an actual central body, though he 

 sometimes qualifies it by stating the alternative of a central 

 body or a central point. He contends for the probability 

 of different creations of the kind of which the milky way 

 is one ; but he does not seem to have known of more than 

 half a dozen nebulae, and he does not push his views so 

 far as to conjecture that these "cloudy spots" are them- 

 selves other such creations : he rather refers them to 

 condensations occurring in the mass of stars to which our 

 sun belongs. His prediction of the ultimate resolution of 

 Saturn's rings into congeries of small satellites remains to be 

 verified ; but it is thought by some to be most probable 

 that such is the truth. It is hardly necessary to say that 

 Wright supposes mutual gravitation to be the connecting 

 agent between star and star, as well as between stars and 

 their planets. 



Kant adds to what he probably learnt from the review 

 of Wright, the distinct supposition that the nebulae are 

 other specimens of constellative systems, and that these 

 systems, with our own, may be but parts of a larger one, 

 and so on. He also declares for Sirius as the central 

 body of our system. Wright considers Sirius merely as 

 our nearest neighbour. 



There is an account of Thomas Wright (with a good 

 portrait) in the Gentleman's Magazine for 1793, vol. Ixiii. 

 pp. 9, 126, 213. He was born at Byer's Green, about six 

 miles from the city of Durham, September 22, 1711, the 

 son of a carpenter, a small landholder. He was apprenticed 

 to a clock-maker, then went to sea, and afterwards struggled 

 for many years as a maker of almanacks, a lecturer, and a 

 teacher of mathematics. During this time he published 

 some works. At last he seems to have risen into note as 

 a teacher of the sciences in noble families; and we find 

 him in affluence towards the end of his life, but how it 

 came is not stated. He built himself a handsome house 

 at Byer's Green in 1756-62, and died there February 25, 



