89 
A brief review of what the authorities have taught us 
shows that we have really up to the present time no 
reliable data upon which to base an opinion. 
After examining the statements of Camden, Horsley, the 
Whitakers, Ormerod, and others, the measures of the true 
earth and of Ptolemy’s world were given, and, it was shown 
that, so far as the subject of the present paper was con- 
cerned, the proportion of six to five might be safely adopted. 
This was the ratio of the scales adopted by Dr. Whitaker in 
the earliest years of the century, and by others since. 
Commencing at Ianganorum prom : the positions and the 
errors of each of the stations in succession were examined 
and determined, with the following results : — 
Tisobius fl : 
Ianganorum prom : 
Mona. 
Seteia Est. : 
Belisama Est. : 
Setantiorum portus : 
Moricambe Est. : 
Ituna Est. : 
Traeth Mawr. 
Brach y pwll. 
Isle of Man. 
Dee. 
Mersey. 
Ribble. 
Morecambe. 
Solway. 
The application of the name of Tisobius to the Conway 
was shown to have resulted from the same editorial error 
which has cut off the promontory of Caernarvonshire in the 
whole of the editions of the Geography. 
The extraordinary width of the Wirrall, and the conse- 
quent differences of opinion as to the true name of the 
Belisama, was proved to have resulted from the fact that 
the Seteia is placed too low, and not the Belisama too high. 
This error being corrected, all the stations are consistent to 
Morecambe. 
The contraction of the coast between Moricambe and 
Ituna was explained and verified by calculation. 
The absence of Anglesea from the Geography of Ptolemy, 
and the fact that his Mona is the Isle of Man “ pure and 
simple ” were elucidated and the paper concluded with some 
remarks upon the value of the sevei’al editions of Ptolemy’s 
work. 
