midnight
`` All his things are in the tent . He just slipped out without a thing with him except his pocket knife . '' Bart himself had not believed the suggestion about night-fishing , but he did not know what other explanation to make of Frank 's absence . Once more , toward midnight , the boys fired other signaling shots , but without avail . Then , with hopelessness , and something very much like fear in their hearts , they went back to the tent . `` We 'll go to sleep , and make a good search in the morning , '' said Bart . `` Why this is nothing after all .