168 Transactions. — Miscellaneous. 



memory is recalled to the zoological student in the masticatory 

 apparatus of Echinus, known as x\ristotle's lantern. Such 

 was the authority of the Aristotelean views that they were 

 held and reproduced by the Eomans down to the close of the 

 Middle Ages. 



All maps or charts previous to Aristotle's time were merely 

 pictorial sketches devoid of scale or proportion ; but a pupil 

 of Aristotle's — DiccBarchus — divided the representation of the 

 known world by a longitudinal line in the sense of our equator, 

 along which stadia were marked. By this means it was pos- 

 sible to express relative distances more precisely than formerly. 

 This departure was followed up by Eratosthenes, of Cyrene, 

 director of the library of the museum at x\lexandria, who, 

 encouraged by the patronage of the Ptolemies, arranged the 

 geographical facts collected by the generals of Alexander, 

 using the prin>e longitude of Dicoearchus, which passed 

 through Rhodes. To this he added three others, passing 

 respectively through Alexandria, Syene, and Meroe. He also 

 traced at right angles to these a meridian line passing through 

 Rhodes and Alexandria southwards to S}'ene via Meroe. 

 Eratosthenes reformed the principles of geography, and gave 

 it a more systematic form. He adopted the view of Aristotle 

 and Euclid regarding the figure and jjosition of the earth, 

 looking upon it as a sphere placed in the centre of the uni- 

 verse, around which the celestial bodies moved every twenty- 

 four hours, the sun and moon having independent motions of 

 their own. For all practical purposes, his views differed only 

 from those of modern geographers in having a geocentric 

 instead of an heliocentric standpoint. 



When the Romans had extended their dominions to Egypt 

 they were able to acquire the geographical knowledge pos- 

 sessed by the school of Alexandria ; but the genius of the con- 

 quering people was not directed towards scientific research, 

 nor did they encourage navigation and commerce with the 

 same ardour as their predecessors. The science of ocean- 

 ography was not advanced among them as among the 

 Greeks by the speculations of philosophers, or by the study of 

 natural phenomena for their own sakes. It was only the 

 luxury of imperial Rome, which gave rise to the demand for 

 the varied products of all the countries of the known world, 

 that led to active trade by land and sea. It seems natural to 

 expect that the Romans, who carried their victorious armies 

 throughout nearly all the world known to the ancients, should 

 have left son:ie important documents relating to the physical 

 aspects of nature in the regions over which they extended their 

 conquests. Although the Roman rule extended over a great 

 extent of coast bordering on the Atlantic, they never organized 

 any voyages of discovery into the outer sea, after the manner 



