The Thundering Herd 71 



the northern horizon what at first seemed 

 to be a cloud of smoke. 



At the thought of a prairie fire upon such 

 a parched area as these plains, a horrible 

 fear seized upon the little party, and Mr. 

 Anderson hurried to the top of the nearest 

 swell to learn if their worst fears were true. 



On mounting the eminence, he discovered 

 that the cloud extended from the east to 

 the west as far as the eye could reach. It 

 certainly was not smoke, but each minute 

 it grew in density and volume, like a 

 menace, something dark and foreboding 

 that would engulf them. 



Presently as he watched, he thought he 

 heard a low rumbling, like the first indis- 

 tinct sounds of thunder, and putting his ear 

 to the ground in Indian fashion, he could 

 hear the rumbling quite plainly. It was 

 like the approach of a mighty earth- 

 quake, only it traveled much slower; 

 like the rumbling of the surf; like the 



