five o'clock
`` Because , '' said Mr. Harvey , `` salt can not be changed to vapor , and it is too heavy to be raised , in any quantity , in the air with the water . Yet , I suppose , that a little salt is always mixed with the bubbles that form clouds . '' This afternoon was very hot , and the boys spent it in their room , arranging their books and pictures , and in reading . At five o'clock , while Thomas was standing by the window , he suddenly exclaimed : `` There 's a hawk ! '' Both the boys ran to the window , and saw a large hawk , sailing slowly toward the barn . `` He is the one that steals our chickens , '' said John . `` And see , he 's flying straight for the barn .