120 LECTURES. 



by astronomers and mathematicians for that especial object. Cyrus 

 of Persia, Augustus of Rome, and the Emperor Charlemagne^ after 

 having accomplished their military work, sat down, and surveyed and 

 painted it. Even Joshua, as we are told in the Bible, did this with 

 his little territory of Palestine, when he had settled there the twelve 

 tribes. 



From this class of maps, made by conquerors and distributors of 

 land, have grown our official government surveys, which often are 

 very valuable, because they are made without a too great fear of 

 expense. They generally contain the most important information as 

 regards the political divisions of the country, and for the adjustment 

 of boundary questions. Sometimes, being particularly destined for 

 government use, they have not been given to the public, or at least not 

 to any great extent. With respect to America we have many most 

 important publications of this character, made by the French and 

 British governments for Canada ; by the British atlmiralty for nearly 

 every part of America ; by the Spanish hydrographical depot in 

 Madrid for Spanish America; and by the Land Office, Topographical 

 Bureau, the Coast Survey Office, and other branches of the United 

 States government, for different parts of the territory of the United 

 States. The governments of Brazil, of New G-ranada, and other 

 South American States, have likewise caused splendid publications to 

 be made descriptive of the territories under their dominion. 



The observation of the stars and the movements of the other 

 heavenly bodies seems to have attracted the attention of all nations at 

 a very early stage of their civilization. And at a no less early period 

 questions arose respecting the origin, formation, extent, and configu- 

 ration of the world inhabited by us — questions which are intimately 

 connected with astronomy. The attempt to depict to the eye the 

 result of the investigations that ensued naturally led to the construc- 

 tion of the first astronomical and cosmographical maps. 



But astronomy, although a very ancient science, remained in an 

 infant state for thousands of years, and the first steps in the progress 

 of navigation and discovery were very slow. We may say that, until 

 the time of Columbus and Gama, nations had no accurate knowledge 

 except of their immediate neighborhoods, and their deeds were per- 

 formed on a very narrow stage. Hence, for thousands of years, the 

 art of constructing maps made very little progress. The maps which 

 were in use in the time of Columbus are not much better than those 

 which the Alexandrian geographer Agathodasmon had composed for 

 the work of Ptolemy a thousand years before. They do not include 

 a greater extent of country, they exhibit no other facts, neither do 

 they show any great improvement as regards the position of locali- 

 ties upon the' earth's surface. In fact, the old maps of Ptolemy's 

 Geography were even then considered as a great authority, and were 

 often copied exclusively. 



After the discovery of America and the countries bordering on the 

 Pacific ocean and tlie Indian sea, the extent of the known and habi- 

 table world was much increased and the figure of tlie continents 

 and the limits of the oceans were more correctly given on the 

 maps. But it was still very long ere the classes of interesting facts 



