GEOGRAPHICAL SCIENCE. 



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merce of Phoenicia and Egypt, and he used it to prepare more detailed and 

 correct maps than were at that time in use, and to compose a book of 

 geography, which, though no longer in existence, is copied from by Ptolemy. 

 That writer says of him, " Marinus of Tyre, the latest of our contemporaries 

 who has cultivated geography, seems to have done it to some purpose, for 

 it is evident that he has made several additions to the former knowledge 



Fig. 192. Map of the Roman World. Taken from the " Liber Guidonis." Manuscript dated 

 1119 (No. 3,898). In the Burgundy Library, Brussels. 



of this subject, and that he has corrected earlier writings which contained 

 errors that had at first misled him as well as others. This is seen very 

 clearly in his corrections of the Geographical Table." Previously to Marinus 

 of Tyre, a Roman citizen, Pomponius Mela, had written a useful treatise on 

 geography, entitled, " De Situ Orbis," in which he described the countries of 

 the known world, following the circumference of the seas, and beginning with 



