68 



SCIENCE ABSOLUTE OF SPACE. 



angles of the triangle have necessarily been 

 equal to four right angles. 



"The answer to which is, that there is no 

 connexion between the things at all, and that 

 the result will just as much take place where 

 the exterior angles are avowedly not equal to 

 four right angles. 



* 'Take, for example, the plane triangle formed 

 by three small arcs of the same or equal circles, 



as in the margin; 

 and it is manifest 

 that an arc of this 

 circle may be car- 

 ried round pre- 

 cisely in the way 

 described and re- 

 turn to its old sit- 

 uation, and yet 

 there be no pre- 

 tense for infer- 

 ring that the exterior angles were equal to 

 four right angles. 



"And if it is urged that these are curved 

 lines and the statement made was of straight; 

 then the answer is by demanding to know, 

 what property of straight lines has been laid 

 down or established, which determines that 

 what is not true in the case of other lines is 



