GEOGRAPHY AND TOPOGRAPHY. H 



which are allowed to run loose in the woods, may have been important fac- 

 tors in offering opportunities for acorns, etc., to take root. As we approach 

 the western border of the timber belt the short leaf pine disappears altogether, 

 and the forests are composed of the other woods mentioned above, especially 

 post oak, blackjack, hickory, and ash. As we continue north and northwest 

 through the timber belt, we again emerge into an undulating prairie country, 

 which extends thence into Central and West Texas. The soil is a very fertile 

 black clay, and cottonwood follows the courses of the streams until they 

 finally disappear in the forests to the east. East Texas is well watered, not 

 only by rivers and creeks, but by numerous springs and a rainfall which, 

 though not confined to any special part of the year, is most plentiful from 

 December until April. Unlike the country to the west, it rarely suffers from 

 severe drought. Lakes are of very rare occurrence, and are never seen except 

 in river bottoms, where they form muddy lagoons, abounding in fish and gen- 

 erally fed by springs. They are often of considerable depth, and are con- 

 nected with the main river by narrow channels. The only instance of an up- 

 land lake seen by the writer in East Texas is in Freestone County, some five 

 miles west of the Trinity River, and amounts to little more than a large 

 spring. It is a small circular body of clear water, occupying a depression in 

 the clayey strata, some two hundred yards in diameter, and fed by springs. 

 It empties into the Trinity River and occupies an elevation of 175 feet above 

 it. The absence of lakes in this country is due to two causes : 



1. The porous nature of the sandy strata which underlie the country and 



which form the ready channel for the subterranean drainage of a possi- 

 ble lake basin. 



2. The softness of the strata, which renders the natural cutting of channels 



a very rapid process, and consequently makes the existence of a closed 

 basin suitable for a lake almost impossible. 



In spite of the low elevation of many parts of East Texas, swamps are 

 rare, and in most places entirely unknown. The few that do exist are found 

 along the rivers and in the coast bayous, near their mouths, especially in the 

 lower part of the Sabine and thence towards the Trinity. 



The main rivers of East Texas are the southwesterly (coastward) continua- 

 tion of the great rivers of the prairie country. They all preserve a general east- 

 erly or southeasterly course, and in the low coast prairie country, as they 

 reach base level, become very crooked and meandering. In the rivers of 

 Texas there is no well defined "fall line," as described by McGee* and others 

 in the Atlantic States. The rivers are often very swift in their upper courses, 

 and become more and more sluggish as they enter the timber and approach 



* "Three Formations of the Middle Atlantic Slope," "W. J. McGee, American Journal of 

 Science, Yol. XXX Y, p. 120, February, 1888. 



