By this time the professor and the other boys came riding up, along with the guide. Hockley’s mule kept dancing around, and they had to move from one spot to another to keep out of the way. “Better get off!” began Professor Strong, when of a sudden the mule made a sudden bolt forward. Four leaps took the animal to the low wall of the cistern and here he stopped abruptly. Then up went his rear hoofs like lightning and in an instant Hockley was thrown into the air. Down came the youth head first, to strike the water with a loud splash, and then he disappeared from sight. A perfect roar of laughter went up, both from the boys and from the natives, and Professor Strong kept a straight face with difficulty. It was a truly comical sight, and when Hockley came up the boys had to laugh still more. In going down the lank youth’s head had touched the unclean bottom of the cistern and now his hair and face were covered with a greenish mud and slime awful to behold. “Hel--help me out, somebody!” he spluttered, blowing the water from his mouth. “I’ll help you,” answered the professor, and leaping to the ground he gave the unfortunate one his hand. Getting out of the cistern was easy and in a moment more Hockley stood in the roadway brushing the water and dirt from him and glaring savagely at Darry and the others. “It ain’t no laughing matter!” he howled. “You shut up, or I’ll give you something to laugh about.” “It’s too bad, Glummy,” began Mark, when he could suppress his feelings sufficiently to speak. “But you did look so funny----” “I don’t want you to talk to me!” stormed Hockley, working himself up into a perfect rage. “You are all against me. I’m going back to the city, and maybe I’ll start for home to-morrow.” “Be calm, Jacob,” put in the professor. “It was truly unfortunate, but there is no occasion for making matters worse by losing control of your temper. I dare say if I had been thrown into the cistern all of you would have laughed just as hard.” “I don’t care, they are all down on me!” grumbled Hockley. “I believe you only imagine it. Come, we will find some place where you can wash up and have your clothing dried.” “I’ll go back to the hotel and change my clothing. I don’t want to see the caves.” Hockley was obdurate, and in the end he was allowed to depart, after having washed up in a nearby hut. A native conducted him back to the city, so that he might not lose his way. Once at the hotel he lost no time in getting some liquor and a package of cigarettes, and, in the privacy of a room the party had engaged, lay down to read another “thriller” he had purchased before leaving Havana. But he was full of bitterness, and his resolve to “fix” the others was greater than ever.