LECTURES. 



121 



represented on the maps were enlarged and the manner of depicting 

 them improved. 



Sometimes, it is true, an attempt was made to represent on the 

 maps certain physical features of the earth, resulting from geograpiiical 

 position. Thus, for instance, we have very old maps on which the 

 whole torrid zone is overlaid Avith a glowing purple color, to indicate 

 the extreme heat of that part of the world. Here we see the first 

 rude hciiinning of thermographic maps. When the great discoveries 

 of the iPortugese and Spaniards had astonished the civilized world 

 with the sight of the strange products of harharous regions and with 

 the accounts of the savage customs of their inhabitants, it became 

 the fashion among chartographers to embellish the different countries 

 and islands on their maps with figures of grotesque apes, of enormous 

 snakes, of birds of brilliant plumage, of the precious pepper and 

 clove tree, and of the fightings, butcherings, and feastings of can- 

 nibals. These representations also did good service in handsomely 

 filling up vacant spaces, and thus, in a measure, concealing the artist's 

 ignorance of the interior of the countries delineated. _ As these figures 

 were not very accurately distributed, according to latitude and longi- 

 tude, we see in them our zoological and mineralogical maps only in a 

 very embryonic condition. 



It appears particularly strange that the ocean should have remained 

 for 60 long a time a perfect blank on the maps. Water for the old 

 map-makers was nothing but water, and they represented the whole 

 aqueous surface of our globe as a perfectly unvaried desert, on which 

 no interesting change of any kind could be observed, and which, 

 therefore, they colored blue throughout or covered with uniform lines 

 and stripes. It did not occur to them that the surface of the ocean 

 offers nearly as much variety in color, depth, temperature, and fitness 

 for locomotion as the surftice of the dry land itself. And long after 

 they had become acquainted with many of these peculiarities they did 

 not mark tliem on the maps. 



That the ocean, Ih certain parts, was covered with sea-weed was 

 known since the first voyage of Columbus. Indeed, we find the so- 

 called Sargasso sea alluded to in much earlier voyages of the Portu- 

 guese along the coast of Africa, And yet nobody tried to indicate this 

 remarkable ieature on the marine maps, as had been done long before 

 with the deserts of Sahara and other variations of the surface of the 

 dry land. 



The Spaniards very well knew that some parts of the ocean are 

 rough and boisterous nearly all the year round, while others are 

 almost always calm. They had invented for these different states of 

 the ocean the most expressive terms : they called a certain rough part 

 of the ocean ''el Golfo de los Caballos," (the Horses' gulf,) and a cer- 

 tain quiet one " d Golfo de las Damas," (the Ladies' gulf.) Yet 

 though they painted the difference so well in words they never at- 

 tempted to express it by colors. 



That there were certain regular currents in the ocean was also an 

 earlv discovery. The great Gulf-stream, for instance, was known as 

 early as 1512, or since the first voyage of Ponce de Leon to Florida. 

 This Gulf-stream is particularly well and completely described in 



