76 CONTAGIOUS DISEASES OF DOMES TICATED ANIMALS. 



whicb have resisted the coutagiou ou the infected farms becoming vic- 

 tims to the virus already within their bodies, when their vital resistance 

 is lowered by great fatigue. 



At Dalton there is a probability that permanent infection existed be- 

 fore the war, but not to the same extent as at present. The cattle 

 driven from South Georgia to provision the armies, and later those 

 brought by the refugees returning to their homes, are believed to have 

 been the means of distributing and intensifying thecontagion throughout 

 Northwest Georgia. 



TENNESSEE. 



The line of the infected district crosses the boundary line between 

 Georgia and Tennessee near the western slope of the mountains, and fol- 

 lows a northwesterly direction to Parkville and Benton, in Polk County; 

 then its direction is nearly directly west to Cleveland, Bradley County, 

 and to Snow Hill and Harrison, in James County. From this point the 

 river becomes the line across Hamilton County, Chattanooga and the 

 Chickamauga Valley having been infected for a long time. The south- 

 western part of Polk and the southern parts of Bradley, James, and 

 Hamilton Counties are, tlierefore, permanently infected. The district 

 infected is here, as we have found to be the case elsewhere, extending 

 slowly toward the north ; and though this extension is slow it is ap- 

 parently continuous, and the territory once overrun is seldom redeemed 

 from the scourge. The points which we have mentioned as existing on 

 the border line of the district have only been infected within a few 

 years, and, as elsewhere in newly infected sections, it is the commons 

 rather than the farms that are dangerous, and even the commons are 

 uot uniformly affected. 



In Marion County the line of infection passes in a northwesterly di- 

 rection up the east side of the Sequatchie Valley and within one or two 

 miles of the Sequatchie County line, and then crosses the valley and 

 down the west side for five or ten miles, passing around the mountain 

 range and taking a southwesterly direction to the vicinity of Jasper ; 

 from here the direction is again northwesterly to Decherd, in Franklin 

 County, the greater part of this county being apparently permanently 

 infected. From Decherd the diiectiou of the line is slightly south of 

 west to Fayetteville, in Lincoln County, and trom this point along the 

 Elk River to the Alabama State line in the vicinity of Veto Station. 

 The southern part of Lincoln County is what is called the barren region, 

 and has been infected for many years. In the vicinity of Marbut's the 

 line again crosses into Tennessee, taking a northwestern direction, and 

 at the county line between Giles and Lawrence Counties is about five 

 miles north of the Alabama State line. On the boundary between Law- 

 rence and Wayne Counties this line is 10 miles north of Alabama. At 

 this point there is a sudden l)end toward the north, the line crossing to 

 the northwestern corner of Wayne County, taking in about one fifth of 



