four o'clock
So the order was issued , and late in the afternoon of June 30th , in a pouring rain , the camps were broken , and the drenched army eagerly began its forward movement . Lawton 's division marching off to the right slipped and stumbled through the mud along a narrow , almost impassable , trail over the densely wooded hills until eight o'clock that evening , when , within a mile of Caney , it lay down for the night in the wet grass without tents or fire , and amid a silence strictly enjoined , for fear lest the Spaniards should discover its presence , and run away before morning . At the same time Wheeler 's division of dismounted cavalry , including the Rough Riders and Kent 's infantry division , advanced as best it could over the horrible Santiago road , ankle-deep in mud and water , to El Poso Hill , on and about which it passed a wretchedly uncomfortable night . Seven thousand heavily equipped men , mingled with horses , artillery , pack-mules , and army wagons , all huddled into a narrow gully slippery with mud , advance so slowly , however eager they may be to push forward , that although the movement was begun at four o'clock , midnight found the rearmost regiment still plodding wearily forward . With the coming of daylight , on July 1st , the army lay beneath a dense blanket of mist that spread its wet folds over the entire region they were to traverse . It was eight o'clock before Grimes 's battery of four light field-pieces , posted on El Poso Hill , opened an ineffective fire upon the heights across the broad valley . For twenty minutes the Spaniards paid no attention to the harmless barking of the little guns ; then the smoke cloud hanging over them proved so admirable and attractive a target that they could no longer resist firing at it .