Mr. J. H. Rigg 071 a Corollary hy Prof. J. Thomson. 285 



In the work of Ethicus on geography, said to be translated 

 by St. Jerome, and if so of a very early period, reference is 

 made to the existence of large islands in the Atlantic Ocean. 

 It may also be remarked, that there are several tales extant, 

 as early as the fifth and sixth centuries, in which are men- 

 tioned several instances of seamen having been driven greatly 

 out of their course from the coast of Spain, and reaching di- 

 stricts never previously visited by Europeans; the Saxons 

 even were accustomed to go to Rome all the way by sea, and 

 it is not unlikely that some of them may have traversed the 

 Atlantic : otherwise how can we account for the general no- 

 tion which certainly did exist of a country far to the west- 

 ward beyond the sea, and not coincident with the eastern 

 boundaries of the Old World ? 



The terrestrial paradise of the middle-ages may possibly 

 have been America; Maundevile, who we must remember 

 was travelling towards the east, describes it as being situated 

 far beyond India. Again, we could hardly expect that the 

 Chinese had not, from a remote period, the knowledge of the 

 existence of a continent in such a relative position to them ; 

 and this may account for the tradition current in the East, and 

 a further confirmation of which was not likely to be obtained 

 from that people. From the obstacle thus placed to the free 

 discussion of discovery on the eastern boundary of the Old 

 World, and the difficulty of proving by experience any iso- 

 lated facts obtained primarily from the vicissitudes of the sea 

 on the western, it is not surprising that we find legend on 

 the one hand and uncertain tradition on the other. 



It may be necessary to observe that the preceding notices 

 could have no reference whatever to the discovery of America 

 by the Northmen in the tenth century. 



XL. On the Corollary deduced hy Professor J. Thomson, 

 from the Proiwsition demonstrated by him in the Number far 

 July. By James H. Rigg. 



To the Editors of the Philosophical Magazine and Journal. 

 Gentlemen, 

 "VTOUR insertion of the following correction of part of a 

 -■- communication which appeared in your last, in an early 

 Number of your Magazine, will oblige yours truly, 

 July 20, 1839. James H. Rigg. 



Professor Thomson gives and demonstrates the following 

 Prop. " Let ABC be a A, and through any point P in 

 its plane, let A D, B E, C F be drawn, cutting the sides, or 

 the sides produced in D, E, F : through D, E, F, desc. a b 



