It must have been after midnight when Blake was suddenly aroused by a peculiar whistling noise. At first he thought he was in New York and that the fire engines were passing. Then he was more fully aroused by a nudge from Joe. “What’s the matter?” asked Blake. “Something’s going on!” cried his chum. “There’s a row at the water hole. The sentinels are all excited.” Once more that peculiar whistling grunt sounded. “Rhinos!” exclaimed Sergeant Hotchkiss from the next tent. “And a fight is on at the pool. Boys, if you had a flashlight you could get a dandy picture now!” “We’ve got a long-burning one!” cried Blake. “Let’s try it, Joe! Let’s try for a night picture.” “I’m with you!” exclaimed his chum, tumbling out, while the excitement at the water hole grew, and there came many cries from the natives. CHAPTER XVI A RHINOCEROS CHARGE “Where’s that flash powder, Blake?” “I don’t know. Hand me my shoes, will you?” “There they are, right by your cot. Don’t knock that camera over!” “Say, you fellows are so excited you don’t know whether you’re standing on your head or on your heels,” complained C. C. Piper, as he looked into the tent, lighted by a swinging lantern. Indeed Joe and Blake were somewhat upset at the prospect of making a new kind of moving picture. “Oh, we’ll get there after a bit,” said Blake, as he completed dressing. Joe, too, was soon ready and got out the cameras. Meanwhile the native porters, learning that they were not expected to get out and assist at a night hunt, had ceased their excited cries. Mr. Duncan took occasion to warn the boys to be careful and then went back to his tent. “But I suppose I’d better go with you,” remarked Mr. Piper, grimly, as he looked to his gun. “There’s no telling but what you might try to get too close a view of Mr. Rhino.” “And, if you don’t mind, I’ll trail along, too,” said the sergeant. “I haven’t often watched a night scene at a water hole; especially one lighted up.” “I hope our plan works,” spoke Joe. “It’s a sort of experiment, making a light that will give the brilliancy of a flash, and yet last long enough to get a series of views.” “How did you fix it?” asked Sergeant Hotchkiss. “Oh, we used some magnesium and other chemicals,” explained Blake. “Mr. Hadley told us about it. Are you ready there, Joe?” “Sure thing.” “Plenty of film in the camera?” “A thousand feet.” “That ought to be long enough. How about the light?” “It’ll burn for half an hour, I think.” “That’s good. Now if the beasts don’t get scared when they see the flash, and leave the water hole, we ought to get a dandy film. Come on, I’m ready.” They started from their camp, passing out of the ring of thorn bush used as a fence, making toward the water hole. “Wow, listen to that!” cried Blake, as a vibrating roar came from the direction of the drinking place. “A lion, all right,” remarked Joe, grimly. “We may get more of a picture than we bargained for.”